/* ============================================================
   DIGITAL LAB — Design System v2.0
   Premium dark glassmorphism with subject accent colors
   ============================================================ */

/* ── CSS Variables ─────────────────────────────────────────── */
:root {
  /* Base */
  --bg-primary: #050709;
  --bg-secondary: #0a0e16;
  --bg-card: rgba(13, 17, 27, 0.72);
  --bg-card-hover: rgba(18, 24, 38, 0.88);
  --bg-glass: rgba(10, 14, 22, 0.6);
  --border-glass: rgba(255, 255, 255, 0.08);
  --border-glass-hover: rgba(255, 255, 255, 0.16);

  /* Text */
  --text-primary: #f0f2f5;
  --text-secondary: #8b95a8;
  --text-muted: #525c6e;

  /* Subject Accents */
  --physics-primary: #3b82f6;
  --physics-glow: rgba(59, 130, 246, 0.25);
  --physics-bg: rgba(59, 130, 246, 0.08);

  --chemistry-primary: #f97316;
  --chemistry-glow: rgba(249, 115, 22, 0.25);
  --chemistry-bg: rgba(249, 115, 22, 0.08);

  --biology-primary: #22c55e;
  --biology-glow: rgba(34, 197, 94, 0.25);
  --biology-bg: rgba(34, 197, 94, 0.08);

  /* UI */
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 22px;
  --radius-xl: 30px;

  --shadow-sm: 0 2px 8px rgba(0,0,0,0.3);
  --shadow-md: 0 8px 32px rgba(0,0,0,0.4);
  --shadow-lg: 0 20px 60px rgba(0,0,0,0.55);

  --transition-fast: 0.18s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-spring: 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275);

  /* Spacing */
  --section-gap: 56px;
  --content-max-width: 1240px;
}

/* ── Reset ─────────────────────────────────────────────────── */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.65;
  font-size: 15px;
  letter-spacing: -0.01em;
}

/* ── Scrollbar ─────────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.1); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: rgba(255,255,255,0.2); }

/* ============================================================
   NAVBAR
   ============================================================ */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: rgba(5, 7, 12, 0.82);
  backdrop-filter: blur(24px) saturate(1.6);
  -webkit-backdrop-filter: blur(24px) saturate(1.6);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  transition: all var(--transition-smooth);
}

.navbar-inner {
  max-width: var(--content-max-width);
  margin: 0 auto;
  padding: 0 28px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
  transition: opacity var(--transition-fast);
}
.nav-brand:hover { opacity: 0.85; }

.nav-logo {
  font-size: 26px;
  filter: drop-shadow(0 0 10px rgba(59, 130, 246, 0.5));
  transition: transform var(--transition-fast);
}
.nav-brand:hover .nav-logo {
  transform: scale(1.08) rotate(-4deg);
}

.nav-title-group { display: flex; flex-direction: column; }
.nav-title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 17px;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.1;
  letter-spacing: -0.02em;
}
.nav-subtitle {
  font-size: 11px;
  color: var(--text-muted);
  font-weight: 400;
  letter-spacing: 0.5px;
}

.nav-breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-secondary);
}
.nav-breadcrumb .bc-sep { color: var(--text-muted); }
.nav-breadcrumb .bc-current { color: var(--text-primary); font-weight: 500; }


.nav-time {
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  color: var(--text-muted);
  padding: 4px 12px;
  background: rgba(255,255,255,0.04);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-glass);
}

/* ── Language Picker ─────────────────────────────────────────── */
.nav-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.lang-picker {
  position: relative;
}

.lang-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: 'Inter', sans-serif;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  white-space: nowrap;
}
.lang-btn:hover {
  background: rgba(255,255,255,0.09);
  border-color: var(--border-glass-hover);
}
.lang-btn.open {
  background: rgba(59,130,246,0.12);
  border-color: rgba(59,130,246,0.35);
}
.lang-caret {
  font-size: 10px;
  color: var(--text-muted);
  transition: transform var(--transition-fast);
}
.lang-btn.open .lang-caret { transform: rotate(180deg); }

.lang-dropdown {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  background: rgba(12, 17, 28, 0.96);
  border: 1px solid var(--border-glass-hover);
  border-radius: var(--radius-md);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  box-shadow: 0 16px 48px rgba(0,0,0,0.6), 0 0 0 1px rgba(255,255,255,0.04);
  min-width: 190px;
  z-index: 2000;
  overflow: hidden;
  opacity: 0;
  transform: translateY(-6px) scale(0.97);
  pointer-events: none;
  transition: opacity 0.18s ease, transform 0.18s ease;
}
.lang-dropdown.open {
  opacity: 1;
  transform: translateY(0) scale(1);
  pointer-events: all;
}

.lang-dropdown-header {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.8px;
  padding: 10px 14px 6px;
  border-bottom: 1px solid var(--border-glass);
}

.lang-option {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 14px;
  cursor: pointer;
  transition: background var(--transition-fast);
  border: none;
  background: transparent;
  width: 100%;
  text-align: left;
}
.lang-option:hover {
  background: rgba(255,255,255,0.05);
}
.lang-option.lang-active {
  background: rgba(59,130,246,0.12);
}
.lang-option .lang-flag { font-size: 16px; line-height: 1; }
.lang-option .lang-native {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-primary);
}
.lang-option .lang-english {
  font-size: 11px;
  color: var(--text-muted);
  margin-left: auto;
}
.lang-option.lang-active .lang-native { color: #60a5fa; }
.lang-option.lang-active .lang-english { color: rgba(96,165,250,0.6); }

/* Active language indicator dot */
.lang-option.lang-active::before {
  content: '';
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: #3b82f6;
  flex-shrink: 0;
  margin-right: -4px;
}


/* ============================================================
   MAIN CONTAINER
   ============================================================ */
.main-container {
  max-width: var(--content-max-width);
  margin: 0 auto;
  padding: 96px 28px 64px;
  position: relative;
  z-index: 1;
}

.view { animation: fadeInUp 0.4s ease; }
.view.hidden { display: none; }

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ============================================================
   HERO
   ============================================================ */
.hero-section {
  position: relative;
  padding: 48px 0 var(--section-gap);
}

.hero-bg-orbs {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: 0;
  overflow: visible;
}

.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.3;
  animation: orbFloat 16s ease-in-out infinite;
}
.orb-blue {
  width: 500px; height: 500px;
  background: var(--physics-primary);
  top: -120px; left: -100px;
  animation-delay: 0s;
}
.orb-orange {
  width: 450px; height: 450px;
  background: var(--chemistry-primary);
  top: -60px; right: -80px;
  animation-delay: -5s;
}
.orb-green {
  width: 400px; height: 400px;
  background: var(--biology-primary);
  bottom: -100px; left: 35%;
  animation-delay: -10s;
}

@keyframes orbFloat {
  0%, 100% { transform: translate(0, 0) scale(1); }
  25% { transform: translate(40px, -30px) scale(1.08); }
  50% { transform: translate(-30px, 20px) scale(0.95); }
  75% { transform: translate(20px, 10px) scale(1.03); }
}

.hero-content {
  position: relative;
  z-index: 2;
}

.hero-badge {
  display: inline-block;
  padding: 7px 18px;
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.2);
  border-radius: 100px;
  font-size: 13px;
  color: var(--physics-primary);
  font-weight: 500;
  margin-bottom: 24px;
  letter-spacing: 0.3px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.hero-title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: clamp(32px, 5vw, 52px);
  font-weight: 700;
  line-height: 1.08;
  margin-bottom: 20px;
  color: var(--text-primary);
  letter-spacing: -0.03em;
}

.gradient-text {
  background: linear-gradient(135deg, var(--physics-primary), #a855f7, var(--chemistry-primary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 16px;
  color: var(--text-secondary);
  max-width: 560px;
  line-height: 1.75;
  letter-spacing: 0;
}

/* ============================================================
   SECTION LABEL
   ============================================================ */
.section-label {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 24px;
  padding-left: 2px;
}

/* ============================================================
   SUBJECT CARDS
   ============================================================ */
.subject-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 20px;
  margin-bottom: var(--section-gap);
}

.subject-card {
  position: relative;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 28px;
  cursor: pointer;
  transition: all var(--transition-smooth);
  overflow: hidden;
}
.subject-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-glass-hover);
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.subject-card-glow {
  position: absolute;
  top: -50%; left: -50%;
  width: 200%; height: 200%;
  opacity: 0;
  transition: opacity var(--transition-smooth);
  pointer-events: none;
}
.subject-card:hover .subject-card-glow { opacity: 1; }

.subject-physics .subject-card-glow { background: radial-gradient(ellipse at 30% 30%, var(--physics-glow), transparent 60%); }
.subject-chemistry .subject-card-glow { background: radial-gradient(ellipse at 30% 30%, var(--chemistry-glow), transparent 60%); }
.subject-biology .subject-card-glow { background: radial-gradient(ellipse at 30% 30%, var(--biology-glow), transparent 60%); }

.subject-physics:hover { border-color: rgba(59,130,246,0.3); }
.subject-chemistry:hover { border-color: rgba(249,115,22,0.3); }
.subject-biology:hover { border-color: rgba(34,197,94,0.3); }

.subject-icon-wrap {
  width: 56px; height: 56px;
  border-radius: 16px;
  display: flex; align-items: center; justify-content: center;
  margin-bottom: 18px;
  position: relative;
}
.subject-physics .subject-icon-wrap { background: var(--physics-bg); }
.subject-chemistry .subject-icon-wrap { background: var(--chemistry-bg); }
.subject-biology .subject-icon-wrap { background: var(--biology-bg); }

.subject-icon { font-size: 28px; }

.subject-info { position: relative; z-index: 1; }

.subject-name {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 23px;
  font-weight: 700;
  margin-bottom: 6px;
  letter-spacing: -0.02em;
}
.subject-physics .subject-name { color: var(--physics-primary); }
.subject-chemistry .subject-name { color: var(--chemistry-primary); }
.subject-biology .subject-name { color: var(--biology-primary); }

.subject-desc {
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 16px;
  line-height: 1.5;
}

.subject-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.exp-count {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
}

.subject-arrow {
  font-size: 20px;
  color: var(--text-muted);
  transition: transform var(--transition-fast), color var(--transition-fast);
}
.subject-card:hover .subject-arrow {
  transform: translateX(4px);
}
.subject-physics:hover .subject-arrow { color: var(--physics-primary); }
.subject-chemistry:hover .subject-arrow { color: var(--chemistry-primary); }
.subject-biology:hover .subject-arrow { color: var(--biology-primary); }

.subject-tag-list {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  margin-top: 14px;
  position: relative;
  z-index: 1;
}

.subject-tag {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 100px;
  font-size: 11px;
  font-weight: 500;
  border: 1px solid var(--border-glass);
  color: var(--text-secondary);
  background: rgba(255,255,255,0.03);
}

/* ============================================================
   STATS BAR
   ============================================================ */
.stats-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 36px;
  padding: 28px 32px;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.stat-num {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 22px;
  font-weight: 700;
  color: var(--text-primary);
}

.stat-label {
  font-size: 12px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.stat-divider {
  width: 1px;
  height: 32px;
  background: var(--border-glass);
}

/* ============================================================
   SUBJECT HEADER (list view)
   ============================================================ */
.subject-header {
  margin-bottom: 32px;
}

.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-family: 'Inter', sans-serif;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  margin-bottom: 24px;
}
.back-btn:hover {
  background: rgba(255,255,255,0.1);
  color: var(--text-primary);
  border-color: var(--border-glass-hover);
}
.back-arrow { font-size: 16px; }

.subject-header-info {
  display: flex;
  align-items: center;
  gap: 16px;
}

.subject-header-icon {
  width: 56px; height: 56px;
  border-radius: 16px;
  display: flex; align-items: center; justify-content: center;
  font-size: 28px;
}

.subject-header-name {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 28px;
  font-weight: 700;
}

.subject-header-sub {
  font-size: 14px;
  color: var(--text-secondary);
  margin-top: 4px;
}

/* ============================================================
   EXPERIMENT LIST
   ============================================================ */
.exp-list-section { margin-bottom: 40px; }

.exp-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.exp-list-item {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 20px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-smooth);
}
.exp-list-item:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-glass-hover);
  transform: translateX(4px);
  box-shadow: var(--shadow-sm);
}

.exp-item-icon {
  width: 48px; height: 48px;
  border-radius: 14px;
  display: flex; align-items: center; justify-content: center;
  font-size: 22px;
  flex-shrink: 0;
}

.exp-item-info { flex: 1; min-width: 0; }

.exp-item-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.exp-item-desc {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.4;
  display: -webkit-box;
  line-clamp: 2;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.exp-item-arrow {
  font-size: 18px;
  color: var(--text-muted);
  flex-shrink: 0;
  transition: transform var(--transition-fast);
}
.exp-list-item:hover .exp-item-arrow {
  transform: translateX(4px);
}

/* ============================================================
   EXPERIMENT VIEW
   ============================================================ */
.exp-topbar {
  margin-bottom: 24px;
}

.exp-title-wrap {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 8px;
}

.exp-subject-badge {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 100px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.exp-subject-badge.badge-physics { background: var(--physics-bg); color: var(--physics-primary); border: 1px solid rgba(59,130,246,0.2); }
.exp-subject-badge.badge-chemistry { background: var(--chemistry-bg); color: var(--chemistry-primary); border: 1px solid rgba(249,115,22,0.2); }
.exp-subject-badge.badge-biology { background: var(--biology-bg); color: var(--biology-primary); border: 1px solid rgba(34,197,94,0.2); }

.exp-title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 24px;
  font-weight: 700;
}

/* ── Lab Record ────────────────────────────────────────────── */
.glass-card {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  overflow: hidden;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

.lab-record { margin-bottom: 20px; }

.lab-record-toggle {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  background: none;
  border: none;
  color: var(--text-primary);
  font-family: 'Inter', sans-serif;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition-fast);
}
.lab-record-toggle:hover { background: rgba(255,255,255,0.03); }

.toggle-icon {
  font-size: 12px;
  color: var(--text-muted);
  transition: transform var(--transition-fast);
}
.toggle-icon.open { transform: rotate(180deg); }

.lab-record-body {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
}
.lab-record-body.open {
  max-height: 2000px;
}

.lab-record-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  padding: 0 20px 20px;
}

.lab-record-item {
  padding: 14px 16px;
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-sm);
}

.lab-record-label {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 8px;
}
.lab-record-label.lbl-aim { color: var(--physics-primary); }
.lab-record-label.lbl-apparatus { color: var(--chemistry-primary); }
.lab-record-label.lbl-procedure { color: #a855f7; }
.lab-record-label.lbl-precautions { color: #f59e0b; }
.lab-record-label.lbl-conclusion { color: var(--biology-primary); }

.lab-record-text {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.65;
}

.lab-record-list {
  list-style: none;
  padding: 0;
}
.lab-record-list li {
  font-size: 13px;
  color: var(--text-secondary);
  padding: 3px 0;
  padding-left: 16px;
  position: relative;
  line-height: 1.5;
}
.lab-record-list li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--text-muted);
}

/* ── Simulation Area ───────────────────────────────────────── */
.sim-area {
  min-height: 400px;
}

.sim-container {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.sim-canvas-wrap {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  overflow: hidden;
  position: relative;
}

.sim-canvas-wrap canvas {
  display: block;
  width: 100%;
  height: auto;
}

/* Controls Panel */
.sim-controls {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  padding: 20px;
}

.sim-controls-title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.sim-controls-title .ctrl-icon { font-size: 16px; }

.sim-control-row {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 14px;
}
.sim-control-row:last-child { margin-bottom: 0; }

.sim-control-label {
  font-size: 13px;
  color: var(--text-secondary);
  min-width: 120px;
  font-weight: 500;
}

.sim-control-slider {
  flex: 1;
  -webkit-appearance: none;
  appearance: none;
  height: 6px;
  background: rgba(255,255,255,0.08);
  border-radius: 3px;
  outline: none;
  transition: background var(--transition-fast);
}
.sim-control-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px; height: 18px;
  border-radius: 50%;
  background: var(--physics-primary);
  cursor: pointer;
  box-shadow: 0 0 8px rgba(59,130,246,0.4);
  transition: transform var(--transition-fast);
}
.sim-control-slider::-webkit-slider-thumb:hover { transform: scale(1.15); }

.sim-control-slider.slider-chemistry::-webkit-slider-thumb { background: var(--chemistry-primary); box-shadow: 0 0 8px var(--chemistry-glow); }
.sim-control-slider.slider-biology::-webkit-slider-thumb { background: var(--biology-primary); box-shadow: 0 0 8px var(--biology-glow); }

.sim-control-value {
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  color: var(--text-primary);
  min-width: 65px;
  text-align: right;
  font-weight: 500;
}

/* Results Panel */
.sim-results {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  padding: 20px;
}

.sim-results-title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.sim-result-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 14px;
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-sm);
  margin-bottom: 8px;
}
.sim-result-row:last-child { margin-bottom: 0; }

.sim-result-label {
  font-size: 13px;
  color: var(--text-secondary);
}

.sim-result-value {
  font-family: 'JetBrains Mono', monospace;
  font-size: 15px;
  font-weight: 600;
}

/* ── Unified Button System ────────────────────────────────── */
.sim-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 22px;
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-sm);
  font-family: 'Inter', sans-serif;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
  background: rgba(255,255,255,0.05);
  color: var(--text-primary);
  letter-spacing: 0;
  white-space: nowrap;
}
.sim-btn:hover {
  background: rgba(255,255,255,0.1);
  transform: translateY(-1px);
  border-color: var(--border-glass-hover);
}
.sim-btn:active {
  transform: translateY(0);
}
.sim-btn.btn-primary {
  background: linear-gradient(135deg, #3b82f6, #2563eb);
  border-color: rgba(59, 130, 246, 0.4);
  color: white;
  box-shadow: 0 2px 10px rgba(59, 130, 246, 0.2);
}
.sim-btn.btn-primary:hover {
  background: linear-gradient(135deg, #2563eb, #1d4ed8);
  box-shadow: 0 6px 20px rgba(59, 130, 246, 0.35);
  transform: translateY(-2px);
}
.sim-btn.btn-secondary {
  background: rgba(255,255,255,0.06);
  border-color: var(--border-glass-hover);
  color: var(--text-primary);
}
.sim-btn.btn-secondary:hover {
  background: rgba(255,255,255,0.12);
}
.sim-btn.btn-ghost {
  background: transparent;
  border-color: transparent;
  color: var(--text-secondary);
}
.sim-btn.btn-ghost:hover {
  background: rgba(255,255,255,0.05);
  color: var(--text-primary);
}

.sim-btn-group {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

/* Data panel / live data */
.sim-data-panel {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  padding: 20px;
}

.sim-data-title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 14px;
}

.sim-data-row {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 10px;
}

.sim-data-label {
  font-size: 12px;
  color: var(--text-secondary);
  min-width: 130px;
}

.sim-data-bar-track {
  flex: 1;
  height: 6px;
  background: rgba(255,255,255,0.06);
  border-radius: 3px;
  overflow: hidden;
}
.sim-data-bar-fill {
  height: 100%;
  border-radius: 3px;
  transition: width 0.15s ease;
}

.sim-data-value {
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  color: var(--text-primary);
  min-width: 55px;
  text-align: right;
}

/* ── Notebook ──────────────────────────────────────────────── */
.sim-notebook {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  padding: 20px;
}

.sim-notebook-title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.sim-notebook-list {
  list-style: none;
  padding: 0;
  max-height: 180px;
  overflow-y: auto;
}

.sim-notebook-list li {
  font-size: 12px;
  color: var(--text-secondary);
  padding: 4px 0;
  padding-left: 14px;
  position: relative;
  line-height: 1.4;
}
.sim-notebook-list li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--text-muted);
}

/* ── Phase Indicator ───────────────────────────────────────── */
.sim-phase-bar {
  display: flex;
  gap: 4px;
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  padding: 14px 16px;
}

.sim-phase-step {
  flex: 1;
  text-align: center;
}

.sim-phase-bar-track {
  height: 4px;
  border-radius: 2px;
  background: rgba(255,255,255,0.08);
  margin-bottom: 6px;
}
.sim-phase-bar-track.done { background: var(--biology-primary); }
.sim-phase-bar-track.active { background: #f59e0b; }

.sim-phase-label {
  font-size: 11px;
  color: var(--text-muted);
}
.sim-phase-label.active { color: var(--text-primary); font-weight: 600; }

/* ============================================================
   RECENT ACTIVITY SECTION
   ============================================================ */
#recent-activity-container {
  margin-bottom: 40px;
}
.recent-activity-card {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 24px 32px;
  background: linear-gradient(135deg, rgba(255,255,255,0.03) 0%, rgba(255,255,255,0) 100%);
  border: 1px solid var(--border-glass);
  box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.3);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}
.recent-activity-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; width: 100%; height: 2px;
  background: linear-gradient(90deg, transparent, rgba(59, 130, 246, 0.5), transparent);
}
.recent-activity-card:hover {
  border-color: rgba(59, 130, 246, 0.4);
  transform: translateY(-2px);
}
.recent-icon-wrap {
  width: 56px; height: 56px;
  border-radius: 16px;
  display: flex; align-items: center; justify-content: center;
  font-size: 28px;
  flex-shrink: 0;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,0.1);
}
.recent-info {
  flex: 1;
  min-width: 0; /* for truncation if needed */
}
.recent-title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 20px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 12px;
}
.recent-progress-wrap {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.recent-progress-label {
  display: flex;
  justify-content: space-between;
  font-size: 13px;
  color: var(--text-secondary);
  font-weight: 500;
}
.recent-progress-track {
  width: 100%;
  height: 6px;
  background: rgba(0,0,0,0.4);
  border-radius: 3px;
  box-shadow: inset 0 1px 3px rgba(0,0,0,0.5);
  overflow: hidden;
}
.recent-progress-fill {
  height: 100%;
  background: linear-gradient(90deg, #3b82f6, #a855f7);
  border-radius: 3px;
  transition: width 1s cubic-bezier(0.1, 1, 0.2, 1);
  box-shadow: 0 0 10px rgba(168, 85, 247, 0.5);
}
.resume-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  background: var(--physics-primary);
  color: white;
  border: none;
  border-radius: 100px;
  font-family: 'Space Grotesk', sans-serif;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 14px rgba(59, 130, 246, 0.3);
}
.resume-btn:hover {
  background: #2563eb;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(59, 130, 246, 0.4);
}
.resume-arrow {
  transition: transform 0.3s ease;
}
.resume-btn:hover .resume-arrow {
  transform: translateX(4px);
}

/* ============================================================
   GAMIFICATION & PROFILE
   ============================================================ */
/* Nav Profile Btn */
.nav-profile-btn {
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border-glass);
  color: white;
  width: 36px; height: 36px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 16px;
  cursor: pointer;
  transition: all 0.3s ease;
  margin-left: 16px;
}
.nav-profile-btn:hover { background: rgba(59, 130, 246, 0.2); border-color: rgba(59,130,246,0.5); transform: scale(1.05); }

/* Dashboard Rank Card */
.rank-card {
  padding: 24px;
  display: flex; flex-direction: column; gap: 16px;
  position: relative; overflow: hidden;
  transition: all 0.3s ease;
}
.rank-card:hover { transform: translateY(-3px); border-color: rgba(255,255,255,0.15); box-shadow: 0 8px 30px rgba(0,0,0,0.4); }
.rank-card-header { display: flex; align-items: center; gap: 16px; }
.rank-icon-wrap { width: 50px; height: 50px; border-radius: 12px; display: flex; align-items: center; justify-content: center; font-size: 24px; }
.rank-title { font-family: 'Space Grotesk', sans-serif; font-size: 22px; font-weight: 700; }
.rank-progress-labels { display: flex; justify-content: space-between; font-size: 13px; font-weight: 600; margin-bottom: 6px; }
.rank-progress-track { height: 8px; background: rgba(0,0,0,0.3); border-radius: 4px; box-shadow: inset 0 1px 3px rgba(0,0,0,0.5); overflow: hidden; }
.rank-progress-fill { height: 100%; border-radius: 4px; transition: width 1s ease-in-out; }

/* Profile Page */
.profile-glass-header { 
  padding: 40px; display: flex; align-items: center; gap: 30px; margin-bottom: 30px; 
  background: linear-gradient(135deg, rgba(255,255,255,0.05), transparent);
}
.profile-avatar-wrap { width: 100px; height: 100px; border-radius: 20px; display: flex; align-items: center; justify-content: center; font-size: 48px; }
.profile-name { font-family: 'Space Grotesk', sans-serif; font-size: 36px; font-weight: 700; color: white; margin-bottom: 8px; }

.profile-stats-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 20px; margin-bottom: 30px; }
.stat-box { padding: 24px; text-align: center; }
.stat-box-title { font-size: 14px; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 1px; font-weight: 600; margin-bottom: 12px; }
.stat-box-val { font-family: 'JetBrains Mono', monospace; font-size: 36px; font-weight: 700; text-shadow: 0 0 15px currentColor; }

.profile-progression { padding: 30px; margin-bottom: 40px; }

/* Badges */
.badges-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 16px; margin-bottom: 40px; }
.profile-badge-card { padding: 20px 10px; background: rgba(255,255,255,0.02); border: 1px solid var(--border-glass); border-radius: 12px; text-align: center; transition: all 0.3s; }
.profile-badge-card.unlocked { background: rgba(255,255,255,0.06); border-color: rgba(255,255,255,0.2); box-shadow: 0 4px 15px rgba(0,0,0,0.2); }
.profile-badge-card.unlocked .badge-icon { animation: floatBadge 4s ease-in-out infinite; filter: none; opacity: 1; }
.profile-badge-card.locked .badge-icon { filter: grayscale(100%) opacity(0.3); }
.badge-icon { font-size: 40px; margin-bottom: 12px; }
.badge-name { font-size: 13px; font-weight: 600; margin-bottom: 4px; color: var(--text-primary); }
.profile-badge-card.locked .badge-name { color: var(--text-muted); }
.badge-desc { font-size: 11px; color: var(--text-secondary); }

@keyframes floatBadge { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-5px); } }

/* Leaderboard */
.leaderboard-card { padding: 20px; }
.leaderboard-table { width: 100%; border-collapse: collapse; text-align: left; }
.leaderboard-table th { padding: 12px 16px; font-size: 12px; color: var(--text-muted); text-transform: uppercase; letter-spacing: 1px; border-bottom: 1px solid var(--border-glass); }
.leaderboard-table td { padding: 16px; border-bottom: 1px solid rgba(255,255,255,0.02); }
.leaderboard-table tr:last-child td { border-bottom: none; }
.leaderboard-table tr.lb-me { background: rgba(59, 130, 246, 0.1); }
.leaderboard-table tr:hover { background: rgba(255,255,255,0.03); }

/* Toasts & Modals */
.xp-toast { position: fixed; bottom: 30px; right: 30px; background: rgba(16, 185, 129, 0.2); border: 1px solid #10b981; color: #10b981; padding: 12px 24px; border-radius: 100px; font-weight: 700; font-family: 'JetBrains Mono', monospace; z-index: 1000; animation: slideUp 0.3s ease-out, fadeOut 0.5s ease-in 2s forwards; backdrop-filter: blur(10px); }
.badge-toast { position: fixed; top: 100px; right: 20px; display: flex; align-items: center; gap: 16px; padding: 16px 20px; z-index: 1000; animation: slideInRight 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275), fadeOut 0.5s ease-in 3.5s forwards; }
.rankup-modal-overlay { position: fixed; inset: 0; background: rgba(0,0,0,0.8); backdrop-filter: blur(8px); z-index: 2000; display: flex; align-items: center; justify-content: center; animation: fadeIn 0.3s ease; }
.rankup-modal-content { padding: 50px; min-width: 400px; animation: popIn 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275); }

@keyframes slideUp { from { transform: translateY(20px); opacity: 0; } to { transform: translateY(0); opacity: 1; } }
@keyframes slideInRight { from { transform: translateX(50px); opacity: 0; } to { transform: translateX(0); opacity: 1; } }
@keyframes fadeOut { to { opacity: 0; visibility: hidden; } }
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes popIn { from { transform: scale(0.8); opacity: 0; } to { transform: scale(1); opacity: 1; } }
@keyframes pop { 0% { transform: scale(1); } 50% { transform: scale(1.3); } 100% { transform: scale(1); } }

/* ============================================================
   RESPONSIVE
   ============================================================ */
@media (max-width: 768px) {
  :root {
    --section-gap: 40px;
  }
  .navbar-inner { padding: 0 16px; }
  .main-container { padding: 80px 16px 40px; }
  .subject-grid { grid-template-columns: 1fr; }
  .hero-title { font-size: 28px; }
  .hero-section { padding: 32px 0 var(--section-gap); }
  .stats-bar { gap: 16px; padding: 20px; flex-wrap: wrap; }
  .stat-divider { display: none; }
  .sim-control-row { flex-wrap: wrap; }
  .sim-control-label { min-width: 100%; }
  .exp-topbar { margin-bottom: 16px; }
  .subject-header { margin-bottom: 24px; }
  .landing-hero { min-height: 100svh; padding: 80px 20px 60px; }
  .landing-title { font-size: 36px; }
  .landing-desc { font-size: 15px; }
  .landing-pills { gap: 8px; }
  .landing-pill { font-size: 11px; padding: 5px 10px; }
  .landing-cta-btn { padding: 16px 36px; font-size: 15px; }
}

@media (max-width: 480px) {
  .subject-card { padding: 20px; }
  .exp-list-item { padding: 16px; }
  .landing-title { font-size: 30px; }
  .landing-badge { font-size: 11px; padding: 5px 12px; }
}

/* ============================================================
   PHOTOSYNTHESIS STARCH TEST — Experiment Styles
   ============================================================ */
.ps-root { display: flex; flex-direction: column; gap: 14px; padding: 4px 0; }

.ps-topbar {
  display: flex; align-items: center; gap: 16px;
  padding: 12px 16px;
  background: rgba(15,20,30,0.6);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  flex-wrap: wrap;
}
.ps-progress-wrap { flex: 1; display: flex; align-items: center; gap: 12px; min-width: 180px; }
.ps-progress-label { font-size: 12px; font-weight: 600; color: var(--biology-primary); font-family: 'JetBrains Mono', monospace; white-space: nowrap; }
.ps-progress-track { flex: 1; height: 6px; background: rgba(255,255,255,0.08); border-radius: 100px; overflow: hidden; }
.ps-progress-fill { height: 100%; background: linear-gradient(90deg, var(--biology-primary), #84cc16); border-radius: 100px; transition: width 0.5s cubic-bezier(0.4,0,0.2,1); box-shadow: 0 0 8px rgba(34,197,94,0.4); }
.ps-top-btns { display: flex; gap: 8px; flex-wrap: wrap; }
.ps-ctrl-btn { display: inline-flex; align-items: center; gap: 6px; padding: 7px 14px; border-radius: var(--radius-sm); border: 1px solid var(--border-glass); background: rgba(255,255,255,0.05); color: var(--text-secondary); font-family: 'Inter', sans-serif; font-size: 12px; font-weight: 500; cursor: pointer; transition: all var(--transition-fast); }
.ps-ctrl-btn:hover { background: rgba(255,255,255,0.1); color: var(--text-primary); border-color: var(--border-glass-hover); }
.ps-ctrl-btn:disabled { opacity: 0.5; cursor: not-allowed; }
.ps-demo-btn { background: rgba(34,197,94,0.1); border-color: rgba(34,197,94,0.25); color: var(--biology-primary); }
.ps-demo-btn:hover { background: rgba(34,197,94,0.2); border-color: rgba(34,197,94,0.5); color: #4ade80; }
.ps-reset-btn { background: rgba(239,68,68,0.08); border-color: rgba(239,68,68,0.2); color: #f87171; }
.ps-reset-btn:hover { background: rgba(239,68,68,0.15); border-color: rgba(239,68,68,0.4); }
.ps-hint-btn.ps-hint-active { background: rgba(245,158,11,0.15); border-color: rgba(245,158,11,0.35); color: #fbbf24; }

.ps-main-grid { display: grid; grid-template-columns: 220px 1fr 240px; gap: 14px; min-height: 480px; }

.ps-sidebar { background: rgba(15,20,30,0.6); border: 1px solid var(--border-glass); border-radius: var(--radius-md); padding: 14px 10px; display: flex; flex-direction: column; gap: 4px; overflow-y: auto; }
.ps-sidebar-title { font-size: 11px; font-weight: 600; text-transform: uppercase; letter-spacing: 1px; color: var(--text-muted); padding: 0 6px; margin-bottom: 8px; }
.ps-step-item { display: flex; align-items: flex-start; gap: 8px; padding: 9px 8px; border-radius: 8px; cursor: pointer; border: 1px solid transparent; transition: all var(--transition-fast); }
.ps-step-item:hover { background: rgba(255,255,255,0.04); border-color: var(--border-glass); }
.ps-step-item.ps-step-active { background: rgba(34,197,94,0.1); border-color: rgba(34,197,94,0.3); box-shadow: 0 0 12px rgba(34,197,94,0.12); }
.ps-step-item.ps-step-done { background: rgba(34,197,94,0.06); border-color: rgba(34,197,94,0.15); }
.ps-step-item.ps-step-locked { opacity: 0.45; cursor: not-allowed; }
.ps-step-num { font-size: 10px; font-weight: 700; font-family: 'JetBrains Mono', monospace; color: var(--text-muted); min-width: 14px; padding-top: 1px; }
.ps-step-active .ps-step-num { color: var(--biology-primary); }
.ps-step-done .ps-step-num { color: #4ade80; }
.ps-step-icon { font-size: 16px; flex-shrink: 0; }
.ps-step-info { flex: 1; min-width: 0; }
.ps-step-name { font-size: 12px; font-weight: 500; color: var(--text-secondary); line-height: 1.3; }
.ps-step-active .ps-step-name { color: var(--text-primary); }
.ps-step-done .ps-step-name { color: #86efac; }
.ps-step-hint { font-size: 11px; color: var(--text-muted); margin-top: 4px; line-height: 1.4; }
.ps-step-hint.hidden { display: none; }
.ps-step-check { font-size: 13px; color: var(--text-muted); min-width: 16px; text-align: right; }
.ps-step-done .ps-step-check { color: #4ade80; }
.ps-step-active .ps-step-check { color: var(--biology-primary); }
.ps-sidebar-note { font-size: 11px; color: var(--text-muted); text-align: center; padding: 8px 6px 0; border-top: 1px solid var(--border-glass); margin-top: 8px; line-height: 1.4; }

.ps-sim-center { display: flex; flex-direction: column; gap: 10px; }
.ps-canvas-wrap { position: relative; border-radius: var(--radius-md); overflow: hidden; border: 1px solid var(--border-glass); background: #060810; width: 100%; aspect-ratio: 520 / 380; }
.ps-canvas-wrap canvas { width: 100%; height: 100%; display: block; }
.ps-canvas-overlay { position: absolute; inset: 0; display: flex; align-items: center; justify-content: center; background: rgba(6,8,16,0.82); backdrop-filter: blur(4px); z-index: 10; }
.ps-start-card { text-align: center; padding: 32px 28px; max-width: 340px; }
.ps-start-icon { font-size: 52px; margin-bottom: 12px; animation: psLeafPulse 2.5s ease-in-out infinite; }
@keyframes psLeafPulse { 0%,100% { transform: scale(1) rotate(-3deg); } 50% { transform: scale(1.1) rotate(3deg); } }
.ps-start-card h3 { font-family: 'Space Grotesk', sans-serif; font-size: 18px; font-weight: 700; color: var(--text-primary); margin-bottom: 8px; }
.ps-start-card p { font-size: 13px; color: var(--text-secondary); line-height: 1.6; margin-bottom: 20px; }
.ps-big-btn { display: inline-block; padding: 10px 24px; background: linear-gradient(135deg, var(--biology-primary), #84cc16); color: #fff; font-family: 'Inter', sans-serif; font-size: 14px; font-weight: 600; border: none; border-radius: var(--radius-sm); cursor: pointer; transition: all var(--transition-fast); box-shadow: 0 4px 16px rgba(34,197,94,0.3); }
.ps-big-btn:hover { transform: translateY(-2px); box-shadow: 0 6px 24px rgba(34,197,94,0.45); }
.ps-feedback-banner { padding: 10px 16px; border-radius: var(--radius-sm); font-size: 13px; font-weight: 500; animation: psFadeSlide 0.3s ease; }
@keyframes psFadeSlide { from { opacity:0; transform:translateY(-6px); } to { opacity:1; transform:translateY(0); } }
.ps-feedback-banner.hidden { display: none; }
.ps-fb-success { background: rgba(34,197,94,0.15); border: 1px solid rgba(34,197,94,0.3); color: #4ade80; }
.ps-fb-error   { background: rgba(239,68,68,0.15);  border: 1px solid rgba(239,68,68,0.3);  color: #f87171; }
.ps-fb-warn    { background: rgba(245,158,11,0.15); border: 1px solid rgba(245,158,11,0.3); color: #fbbf24; }
.ps-step-desc-box { display: flex; align-items: flex-start; gap: 8px; padding: 10px 14px; background: rgba(15,20,30,0.5); border: 1px solid var(--border-glass); border-radius: var(--radius-sm); font-size: 13px; color: var(--text-secondary); line-height: 1.5; }
.ps-step-desc-icon { flex-shrink: 0; }

.ps-info-panel { display: flex; flex-direction: column; gap: 10px; overflow-y: auto; }
.ps-panel-section { background: rgba(15,20,30,0.6); border: 1px solid var(--border-glass); border-radius: var(--radius-md); padding: 14px; }
.ps-panel-title { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 1px; color: var(--biology-primary); margin-bottom: 10px; }
.ps-obs-items { display: flex; flex-direction: column; gap: 8px; }
.ps-obs-row { display: flex; justify-content: space-between; align-items: center; font-size: 12px; gap: 8px; }
.ps-obs-label { color: var(--text-muted); flex-shrink: 0; }
.ps-obs-value { font-weight: 600; color: var(--text-secondary); text-align: right; font-size: 12px; transition: color 0.5s ease; }
.ps-obs-form { display: flex; flex-direction: column; gap: 8px; }
.ps-obs-form-label { font-size: 11px; color: var(--text-muted); }
.ps-obs-select { width: 100%; padding: 7px 10px; background: rgba(255,255,255,0.05); border: 1px solid var(--border-glass); border-radius: 6px; color: var(--text-primary); font-family: 'Inter', sans-serif; font-size: 12px; cursor: pointer; }
.ps-obs-select option { background: #0f172a; }
.ps-obs-submit-btn { padding: 8px 12px; background: rgba(34,197,94,0.15); border: 1px solid rgba(34,197,94,0.3); border-radius: 6px; color: var(--biology-primary); font-family: 'Inter', sans-serif; font-size: 12px; font-weight: 600; cursor: pointer; transition: all var(--transition-fast); margin-top: 4px; }
.ps-obs-submit-btn:hover { background: rgba(34,197,94,0.25); }
.ps-obs-submit-btn:disabled { opacity: 0.5; cursor: not-allowed; }
.ps-obs-result { font-size: 12px; padding: 8px 10px; border-radius: 6px; line-height: 1.5; }
.ps-obs-result.hidden { display: none; }
.ps-obs-correct { background: rgba(34,197,94,0.12); color: #4ade80; border: 1px solid rgba(34,197,94,0.25); }
.ps-obs-wrong   { background: rgba(239,68,68,0.10); color: #f87171; border: 1px solid rgba(239,68,68,0.25); }
.ps-result-box { font-size: 13px; color: var(--text-secondary); line-height: 1.65; }
.ps-viva-open-btn { width: 100%; padding: 12px; background: linear-gradient(135deg, rgba(99,102,241,0.2), rgba(139,92,246,0.2)); border: 1px solid rgba(99,102,241,0.35); border-radius: var(--radius-sm); color: #a5b4fc; font-family: 'Inter', sans-serif; font-size: 13px; font-weight: 600; cursor: pointer; transition: all var(--transition-fast); }
.ps-viva-open-btn:hover { background: linear-gradient(135deg, rgba(99,102,241,0.3), rgba(139,92,246,0.3)); border-color: rgba(99,102,241,0.5); transform: translateY(-1px); }

.ps-viva-overlay { position: fixed; inset: 0; z-index: 9999; display: flex; align-items: center; justify-content: center; background: rgba(0,0,0,0.75); backdrop-filter: blur(8px); padding: 20px; animation: psFadeSlide 0.25s ease; }
.ps-viva-overlay.hidden { display: none; }
.ps-viva-modal { background: rgba(10,14,26,0.98); border: 1px solid var(--border-glass-hover); border-radius: var(--radius-lg); width: 100%; max-width: 560px; max-height: 88vh; overflow-y: auto; box-shadow: 0 24px 80px rgba(0,0,0,0.7); }
.ps-viva-header { display: flex; align-items: center; gap: 12px; padding: 18px 20px 14px; border-bottom: 1px solid var(--border-glass); }
.ps-viva-title { font-family: 'Space Grotesk', sans-serif; font-size: 17px; font-weight: 700; color: var(--text-primary); flex: 1; }
.ps-viva-score-label { font-size: 13px; color: var(--text-secondary); }
.ps-viva-close { width: 28px; height: 28px; border-radius: 50%; border: 1px solid var(--border-glass); background: transparent; color: var(--text-muted); cursor: pointer; font-size: 13px; transition: all var(--transition-fast); display: flex; align-items: center; justify-content: center; }
.ps-viva-close:hover { background: rgba(239,68,68,0.15); color: #f87171; border-color: rgba(239,68,68,0.3); }
.ps-viva-progress-bar { height: 3px; background: rgba(255,255,255,0.06); }
.ps-viva-progress-fill { height: 100%; background: linear-gradient(90deg, #6366f1, #a855f7); transition: width 0.4s ease; }
.ps-viva-q { padding: 24px 20px; display: flex; flex-direction: column; gap: 14px; }
.ps-viva-qnum { font-size: 11px; font-weight: 600; color: var(--text-muted); text-transform: uppercase; letter-spacing: 1px; }
.ps-viva-qtext { font-family: 'Space Grotesk', sans-serif; font-size: 16px; font-weight: 600; color: var(--text-primary); line-height: 1.5; }
.ps-viva-options { display: flex; flex-direction: column; gap: 8px; }
.ps-viva-opt { padding: 12px 16px; background: rgba(255,255,255,0.04); border: 1px solid var(--border-glass); border-radius: 8px; color: var(--text-secondary); font-family: 'Inter', sans-serif; font-size: 13px; font-weight: 500; text-align: left; cursor: pointer; transition: all var(--transition-fast); }
.ps-viva-opt:hover:not(:disabled) { background: rgba(99,102,241,0.12); border-color: rgba(99,102,241,0.3); color: var(--text-primary); }
.ps-viva-opt:disabled { cursor: not-allowed; }
.ps-viva-opt.ps-vopt-correct { background: rgba(34,197,94,0.15); border-color: rgba(34,197,94,0.45); color: #4ade80; }
.ps-viva-opt.ps-vopt-wrong { background: rgba(239,68,68,0.12); border-color: rgba(239,68,68,0.4); color: #f87171; }
.ps-viva-exp { font-size: 13px; padding: 10px 14px; border-radius: 8px; line-height: 1.6; }
.ps-viva-exp.hidden { display: none; }
.ps-exp-correct { background: rgba(34,197,94,0.1); color: #86efac; border: 1px solid rgba(34,197,94,0.2); }
.ps-exp-wrong   { background: rgba(239,68,68,0.10); color: #fca5a5; border: 1px solid rgba(239,68,68,0.2); }
.ps-viva-summary { text-align: center; padding: 32px 24px; display: flex; flex-direction: column; align-items: center; gap: 8px; }
.ps-viva-grade { font-size: 32px; margin-bottom: 4px; }
.ps-viva-final-score { font-family: 'Space Grotesk', sans-serif; font-size: 48px; font-weight: 700; color: var(--text-primary); }
.ps-viva-final-pct { font-size: 16px; color: var(--biology-primary); font-weight: 600; }

@media (max-width: 900px) {
  .ps-main-grid { grid-template-columns: 1fr; }
  .ps-sidebar { display: grid; grid-template-columns: repeat(3, 1fr); gap: 6px; }
  .ps-sidebar-title, .ps-sidebar-note { grid-column: 1 / -1; }
  .ps-info-panel { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
}
@media (max-width: 600px) {
  .ps-sidebar { grid-template-columns: 1fr 1fr; }
  .ps-info-panel { display: grid; grid-template-columns: 1fr; }
  .ps-top-btns { width: 100%; }
}

/* ============================================================
   WATER TRANSPORT STARCH TEST — Experiment Styles
   ============================================================ */
.wt-root { display: flex; flex-direction: column; gap: 14px; padding: 4px 0; }
.wt-topbar { display: flex; align-items: center; gap: 16px; padding: 12px 16px; background: rgba(15,20,30,0.6); border: 1px solid var(--border-glass); border-radius: var(--radius-md); flex-wrap: wrap; }
.wt-prog-wrap { flex: 1; display: flex; align-items: center; gap: 12px; min-width: 180px; }
.wt-prog-label { font-size: 12px; font-weight: 600; color: var(--biology-primary); font-family: 'JetBrains Mono', monospace; white-space: nowrap; }
.wt-prog-track { flex: 1; height: 6px; background: rgba(255,255,255,0.08); border-radius: 100px; overflow: hidden; }
.wt-prog-fill { height: 100%; background: linear-gradient(90deg, var(--biology-primary), #06b6d4); border-radius: 100px; transition: width 0.5s cubic-bezier(0.4,0,0.2,1); box-shadow: 0 0 8px rgba(6,182,212,0.4); }
.wt-top-btns { display: flex; gap: 8px; flex-wrap: wrap; }
.wt-btn { display: inline-flex; align-items: center; gap: 6px; padding: 7px 14px; border-radius: var(--radius-sm); border: 1px solid var(--border-glass); background: rgba(255,255,255,0.05); color: var(--text-secondary); font-family: 'Inter', sans-serif; font-size: 12px; font-weight: 500; cursor: pointer; transition: all var(--transition-fast); }
.wt-btn:hover { background: rgba(255,255,255,0.1); color: var(--text-primary); border-color: var(--border-glass-hover); }
.wt-btn:disabled { opacity: 0.5; cursor: not-allowed; }
.wt-btn-toggle.wt-btn-on { background: rgba(6,182,212,0.15); border-color: rgba(6,182,212,0.4); color: #22d3ee; }
.wt-btn-demo { background: rgba(34,197,94,0.1); border-color: rgba(34,197,94,0.25); color: var(--biology-primary); }
.wt-btn-demo:hover { background: rgba(34,197,94,0.2); border-color: rgba(34,197,94,0.5); color: #4ade80; }
.wt-btn-reset { background: rgba(239,68,68,0.08); border-color: rgba(239,68,68,0.2); color: #f87171; }
.wt-btn-reset:hover { background: rgba(239,68,68,0.15); border-color: rgba(239,68,68,0.4); }

.wt-grid { display: grid; grid-template-columns: 220px 1fr 240px; gap: 14px; min-height: 480px; }
.wt-sidebar { background: rgba(15,20,30,0.6); border: 1px solid var(--border-glass); border-radius: var(--radius-md); padding: 14px 10px; display: flex; flex-direction: column; gap: 4px; overflow-y: auto; }
.wt-sidebar-hd { font-size: 11px; font-weight: 600; text-transform: uppercase; letter-spacing: 1px; color: var(--text-muted); padding: 0 6px; margin-bottom: 8px; }
.wt-step { display: flex; align-items: flex-start; gap: 8px; padding: 9px 8px; border-radius: 8px; cursor: pointer; border: 1px solid transparent; transition: all var(--transition-fast); }
.wt-step:hover { background: rgba(255,255,255,0.04); border-color: var(--border-glass); }
.wt-s-active { background: rgba(6,182,212,0.1); border-color: rgba(6,182,212,0.3); box-shadow: 0 0 12px rgba(6,182,212,0.12); }
.wt-s-done { background: rgba(6,182,212,0.06); border-color: rgba(6,182,212,0.15); }
.wt-s-lock { opacity: 0.45; cursor: not-allowed; }
.wt-s-num { font-size: 10px; font-weight: 700; font-family: 'JetBrains Mono', monospace; color: var(--text-muted); min-width: 14px; padding-top: 1px; }
.wt-s-active .wt-s-num { color: #06b6d4; }
.wt-s-done .wt-s-num { color: #22d3ee; }
.wt-s-ico { font-size: 16px; flex-shrink: 0; }
.wt-s-name { flex: 1; font-size: 12px; font-weight: 500; color: var(--text-secondary); line-height: 1.3; }
.wt-s-active .wt-s-name { color: var(--text-primary); }
.wt-s-done .wt-s-name { color: #67e8f9; }
.wt-s-chk { font-size: 13px; color: var(--text-muted); min-width: 16px; text-align: right; }
.wt-s-done .wt-s-chk { color: #22d3ee; }
.wt-s-active .wt-s-chk { color: #06b6d4; }
.wt-sidebar-note { font-size: 11px; color: var(--text-muted); text-align: center; padding: 8px 6px 0; border-top: 1px solid var(--border-glass); margin-top: 8px; line-height: 1.4; }

.wt-sim-col { display: flex; flex-direction: column; gap: 10px; }
.wt-picker-row { display: flex; gap: 12px; flex-wrap: wrap; background: rgba(15,20,30,0.5); padding: 10px 14px; border-radius: var(--radius-sm); border: 1px solid var(--border-glass); }
.wt-picker-section { display: flex; flex-direction: column; gap: 6px; border-right: 1px solid rgba(255,255,255,0.05); padding-right: 12px; }
.wt-picker-section:last-child { border-right: none; padding-right: 0; }
.wt-picker-lbl { font-size: 10px; font-weight: 600; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.5px; }
.wt-plant-row { display: flex; gap: 6px; }
.wt-plant-chip { padding: 4px 8px; font-size: 11px; background: rgba(255,255,255,0.05); border: 1px solid var(--border-glass); border-radius: 4px; cursor: pointer; transition: all 0.2s; color: var(--text-secondary); white-space: nowrap; }
.wt-plant-chip:hover { background: rgba(255,255,255,0.1); color: var(--text-primary); }
.wt-plant-chip.wt-chip-active { background: rgba(6,182,212,0.15); border-color: rgba(6,182,212,0.4); color: #22d3ee; }
.wt-dye-row { display: flex; gap: 6px; }
.wt-dye-dot { width: 22px; height: 22px; border-radius: 50%; cursor: pointer; border: 2px solid transparent; transition: transform 0.2s, border-color 0.2s; }
.wt-dye-dot:hover { transform: scale(1.1); }
.wt-dye-dot.wt-dye-active { border-color: white; transform: scale(1.15); box-shadow: 0 0 10px currentColor; }
.wt-slider { -webkit-appearance: none; appearance: none; width: 80px; height: 4px; background: rgba(255,255,255,0.1); border-radius: 2px; }
.wt-slider::-webkit-slider-thumb { -webkit-appearance: none; appearance: none; width: 14px; height: 14px; background: #06b6d4; border-radius: 50%; cursor: pointer; }
.wt-spd-val { font-size: 11px; color: var(--text-secondary); font-variant-numeric: tabular-nums; min-width: 20px; }

.wt-canvas-wrap { position: relative; border-radius: var(--radius-md); overflow: hidden; border: 1px solid var(--border-glass); background: #060810; width: 100%; aspect-ratio: 560 / 400; }
.wt-canvas-wrap canvas { width: 100%; height: 100%; display: block; }
.wt-overlay { position: absolute; inset: 0; display: flex; align-items: center; justify-content: center; background: rgba(6,8,16,0.82); backdrop-filter: blur(4px); z-index: 10; }
.wt-start-card { text-align: center; padding: 32px 28px; max-width: 340px; }
.wt-start-ico { font-size: 52px; margin-bottom: 12px; animation: wtFloat 3s ease-in-out infinite; }
@keyframes wtFloat { 0%,100% { transform: translateY(0); } 50% { transform: translateY(-8px); } }
.wt-start-card h3 { font-family: 'Space Grotesk', sans-serif; font-size: 18px; font-weight: 700; color: var(--text-primary); margin-bottom: 8px; }
.wt-start-card p { font-size: 13px; color: var(--text-secondary); line-height: 1.6; margin-bottom: 20px; }
.wt-big-btn { display: inline-block; padding: 10px 24px; background: linear-gradient(135deg, #0284c7, #06b6d4); color: #fff; font-family: 'Inter', sans-serif; font-size: 14px; font-weight: 600; border: none; border-radius: var(--radius-sm); cursor: pointer; transition: all var(--transition-fast); box-shadow: 0 4px 16px rgba(6,182,212,0.3); }
.wt-big-btn:hover { transform: translateY(-2px); box-shadow: 0 6px 24px rgba(6,182,212,0.45); }

.wt-fb { padding: 8px 12px; border-radius: var(--radius-sm); font-size: 12px; font-weight: 500; animation: psFadeSlide 0.3s ease; }
.wt-fb.hidden { display: none; }
.wt-fb-success { background: rgba(34,197,94,0.15); border: 1px solid rgba(34,197,94,0.3); color: #4ade80; }
.wt-fb-error   { background: rgba(239,68,68,0.15);  border: 1px solid rgba(239,68,68,0.3);  color: #f87171; }
.wt-fb-warn    { background: rgba(245,158,11,0.15); border: 1px solid rgba(245,158,11,0.3); color: #fbbf24; }
.wt-desc-box { display: flex; align-items: flex-start; gap: 8px; padding: 10px 14px; background: rgba(15,20,30,0.5); border: 1px solid var(--border-glass); border-radius: var(--radius-sm); font-size: 13px; color: var(--text-secondary); line-height: 1.5; }

.wt-panel { display: flex; flex-direction: column; gap: 10px; overflow-y: auto; }
.wt-panel-sec { background: rgba(15,20,30,0.6); border: 1px solid var(--border-glass); border-radius: var(--radius-md); padding: 14px; }
.wt-panel-hd { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 1px; color: #06b6d4; margin-bottom: 10px; }
.wt-obs-list { display: flex; flex-direction: column; gap: 8px; }
.wt-obs-row { display: flex; justify-content: space-between; align-items: center; font-size: 12px; gap: 8px; }
.wt-obs-k { color: var(--text-muted); flex-shrink: 0; }
.wt-obs-v { font-weight: 600; color: var(--text-secondary); text-align: right; font-size: 12px; }
.wt-form-lbl { font-size: 11px; color: var(--text-muted); display: block; margin-bottom: 4px; margin-top: 8px; }
.wt-select { width: 100%; padding: 7px 10px; background: rgba(255,255,255,0.05); border: 1px solid var(--border-glass); border-radius: 6px; color: var(--text-primary); font-family: 'Inter', sans-serif; font-size: 12px; cursor: pointer; }
.wt-select option { background: #0f172a; }
.wt-obs-btn { width: 100%; padding: 8px 12px; background: rgba(6,182,212,0.15); border: 1px solid rgba(6,182,212,0.3); border-radius: 6px; color: #06b6d4; font-family: 'Inter', sans-serif; font-size: 12px; font-weight: 600; cursor: pointer; transition: all var(--transition-fast); margin-top: 10px; }
.wt-obs-btn:hover:not(:disabled) { background: rgba(6,182,212,0.25); }
.wt-obs-btn:disabled { opacity: 0.5; cursor: not-allowed; }
.wt-obs-res { font-size: 12px; padding: 8px 10px; border-radius: 6px; line-height: 1.5; margin-top: 8px; }
.wt-obs-res.hidden { display: none; }
.wt-obs-ok { background: rgba(34,197,94,0.12); color: #4ade80; border: 1px solid rgba(34,197,94,0.25); }
.wt-obs-wrong { background: rgba(239,68,68,0.10); color: #f87171; border: 1px solid rgba(239,68,68,0.25); }
.wt-result-box { font-size: 13px; color: var(--text-secondary); line-height: 1.65; }
.wt-viva-btn { width: 100%; padding: 12px; background: linear-gradient(135deg, rgba(168,85,247,0.2), rgba(217,70,239,0.2)); border: 1px solid rgba(168,85,247,0.35); border-radius: var(--radius-sm); color: #d8b4fe; font-family: 'Inter', sans-serif; font-size: 13px; font-weight: 600; cursor: pointer; transition: all var(--transition-fast); }
.wt-viva-btn:hover { background: linear-gradient(135deg, rgba(168,85,247,0.3), rgba(217,70,239,0.3)); border-color: rgba(168,85,247,0.5); transform: translateY(-1px); }

.wt-viva-ov { position: fixed; inset: 0; z-index: 9999; display: flex; align-items: center; justify-content: center; background: rgba(0,0,0,0.75); backdrop-filter: blur(8px); padding: 20px; animation: psFadeSlide 0.25s ease; }
.wt-viva-ov.hidden { display: none; }
.wt-viva-modal { background: rgba(10,14,26,0.98); border: 1px solid var(--border-glass-hover); border-radius: var(--radius-lg); width: 100%; max-width: 560px; max-height: 88vh; overflow-y: auto; box-shadow: 0 24px 80px rgba(0,0,0,0.7); }
.wt-viva-hdr { display: flex; align-items: center; gap: 12px; padding: 18px 20px 14px; border-bottom: 1px solid var(--border-glass); }
.wt-viva-title { font-family: 'Space Grotesk', sans-serif; font-size: 17px; font-weight: 700; color: var(--text-primary); flex: 1; }
.wt-viva-score { font-size: 13px; color: var(--text-secondary); }
.wt-viva-close { width: 28px; height: 28px; border-radius: 50%; border: 1px solid var(--border-glass); background: transparent; color: var(--text-muted); cursor: pointer; font-size: 13px; transition: all 0.2s; display: flex; align-items: center; justify-content: center; }
.wt-viva-close:hover { background: rgba(239,68,68,0.15); color: #f87171; border-color: rgba(239,68,68,0.3); }
.wt-viva-pbar { height: 3px; background: rgba(255,255,255,0.06); }
.wt-viva-pfill { height: 100%; background: linear-gradient(90deg, #a855f7, #d946ef); transition: width 0.4s ease; }
.wt-viv-q { padding: 24px 20px; display: flex; flex-direction: column; gap: 14px; }
.wt-viv-num { font-size: 11px; font-weight: 600; color: var(--text-muted); text-transform: uppercase; letter-spacing: 1px; }
.wt-viv-qtext { font-family: 'Space Grotesk', sans-serif; font-size: 16px; font-weight: 600; color: var(--text-primary); line-height: 1.5; }
.wt-viv-opts { display: flex; flex-direction: column; gap: 8px; }
.wt-vopt { padding: 12px 16px; background: rgba(255,255,255,0.04); border: 1px solid var(--border-glass); border-radius: 8px; color: var(--text-secondary); font-family: 'Inter', sans-serif; font-size: 13px; font-weight: 500; text-align: left; cursor: pointer; transition: all 0.2s; }
.wt-vopt:hover:not(:disabled) { background: rgba(168,85,247,0.12); border-color: rgba(168,85,247,0.3); color: var(--text-primary); }
.wt-vopt:disabled { cursor: not-allowed; }
.wt-vopt-ok { background: rgba(34,197,94,0.15) !important; border-color: rgba(34,197,94,0.45) !important; color: #4ade80 !important; }
.wt-vopt-bad { background: rgba(239,68,68,0.12) !important; border-color: rgba(239,68,68,0.4) !important; color: #f87171 !important; }
.wt-viv-exp { font-size: 13px; padding: 10px 14px; border-radius: 8px; line-height: 1.6; }
.wt-viv-exp.hidden { display: none; }
.wt-exp-ok { background: rgba(34,197,94,0.1); color: #86efac; border: 1px solid rgba(34,197,94,0.2); }
.wt-exp-bad { background: rgba(239,68,68,0.10); color: #fca5a5; border: 1px solid rgba(239,68,68,0.2); }
.wt-viv-sum { text-align: center; padding: 32px 24px; display: flex; flex-direction: column; align-items: center; gap: 8px; }
.wt-viv-grade { font-size: 32px; margin-bottom: 4px; }
.wt-viv-big { font-family: 'Space Grotesk', sans-serif; font-size: 48px; font-weight: 700; color: var(--text-primary); }
.wt-viv-pct { font-size: 16px; color: #a855f7; font-weight: 600; }

@media (max-width: 900px) {
  .wt-grid { grid-template-columns: 1fr; }
  .wt-sidebar { display: grid; grid-template-columns: repeat(3, 1fr); gap: 6px; }
  .wt-sidebar-hd, .wt-sidebar-note { grid-column: 1 / -1; }
  .wt-panel { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
}
@media (max-width: 600px) {
  .wt-sidebar { grid-template-columns: 1fr 1fr; }
  .wt-panel { grid-template-columns: 1fr; }
}

/* ============================================================
   BREAD MOLD FUNGUS (Microorganisms) — Experiment Styles
   ============================================================ */
.bm-root { display: flex; flex-direction: column; gap: 14px; padding: 4px 0; }
.bm-topbar { display: flex; align-items: center; gap: 16px; padding: 12px 16px; background: rgba(15,20,30,0.6); border: 1px solid var(--border-glass); border-radius: var(--radius-md); flex-wrap: wrap; }
.bm-prog-wrap { flex: 1; display: flex; align-items: center; gap: 12px; min-width: 180px; }
.bm-prog-label { font-size: 12px; font-weight: 600; color: #eab308; font-family: 'JetBrains Mono', monospace; white-space: nowrap; }
.bm-prog-track { flex: 1; height: 6px; background: rgba(255,255,255,0.08); border-radius: 100px; overflow: hidden; }
.bm-prog-fill { height: 100%; background: linear-gradient(90deg, #eab308, #ca8a04); border-radius: 100px; transition: width 0.5s cubic-bezier(0.4,0,0.2,1); box-shadow: 0 0 8px rgba(234,179,8,0.4); }
.bm-top-btns { display: flex; gap: 8px; flex-wrap: wrap; }
.bm-btn { display: inline-flex; align-items: center; gap: 6px; padding: 7px 14px; border-radius: var(--radius-sm); border: 1px solid var(--border-glass); background: rgba(255,255,255,0.05); color: var(--text-secondary); font-family: 'Inter', sans-serif; font-size: 12px; font-weight: 500; cursor: pointer; transition: all var(--transition-fast); }
.bm-btn:hover { background: rgba(255,255,255,0.1); color: var(--text-primary); border-color: var(--border-glass-hover); }
.bm-btn:disabled { opacity: 0.5; cursor: not-allowed; }
.bm-btn-toggle.bm-btn-on { background: rgba(234,179,8,0.15); border-color: rgba(234,179,8,0.4); color: #fef08a; }
.bm-btn-demo { background: rgba(34,197,94,0.1); border-color: rgba(34,197,94,0.25); color: #4ade80; }
.bm-btn-demo:hover { background: rgba(34,197,94,0.2); border-color: rgba(34,197,94,0.5); }
.bm-btn-reset { background: rgba(239,68,68,0.08); border-color: rgba(239,68,68,0.2); color: #f87171; }
.bm-btn-reset:hover { background: rgba(239,68,68,0.15); border-color: rgba(239,68,68,0.4); }

.bm-grid { display: grid; grid-template-columns: 220px 1fr 240px; gap: 14px; min-height: 480px; }
.bm-sidebar { background: rgba(15,20,30,0.6); border: 1px solid var(--border-glass); border-radius: var(--radius-md); padding: 14px 10px; display: flex; flex-direction: column; gap: 4px; }
.bm-sidebar-hd { font-size: 11px; font-weight: 600; text-transform: uppercase; letter-spacing: 1px; color: var(--text-muted); padding: 0 6px; margin-bottom: 8px; }
.bm-step { display: flex; align-items: flex-start; gap: 8px; padding: 9px 8px; border-radius: 8px; cursor: pointer; border: 1px solid transparent; transition: all var(--transition-fast); }
.bm-step:hover { background: rgba(255,255,255,0.04); border-color: var(--border-glass); }
.bm-s-ac { background: #eab3081a; border-color: #eab3084d; box-shadow: 0 0 12px #eab3081a; }
.bm-s-dn { background: #eab3080f; border-color: #eab30826; }
.bm-s-lk { opacity: 0.45; cursor: not-allowed; }
.bm-s-num { font-size: 10px; font-weight: 700; font-family: 'JetBrains Mono', monospace; color: var(--text-muted); min-width: 14px; padding-top: 1px; }
.bm-s-ac .bm-s-num, .bm-s-dn .bm-s-num { color: #eab308; }
.bm-s-ico { font-size: 16px; flex-shrink: 0; }
.bm-s-name { flex: 1; font-size: 12px; font-weight: 500; color: var(--text-secondary); line-height: 1.3; }
.bm-s-ac .bm-s-name { color: var(--text-primary); }
.bm-s-dn .bm-s-name { color: #fde047; }
.bm-s-chk { font-size: 13px; color: var(--text-muted); min-width: 16px; text-align: right; }
.bm-s-dn .bm-s-chk, .bm-s-ac .bm-s-chk { color: #eab308; }

.bm-sim-col { display: flex; flex-direction: column; gap: 10px; }
.bm-controls { display: flex; gap: 12px; flex-wrap: wrap; background: rgba(15,20,30,0.5); padding: 10px 14px; border-radius: var(--radius-sm); border: 1px solid var(--border-glass); }
.bm-control-group { display: flex; flex-direction: column; gap: 6px; border-right: 1px solid rgba(255,255,255,0.05); padding-right: 12px; }
.bm-control-group:last-child { border-right: none; padding-right: 0; }
.bm-ctrl-lbl { font-size: 10px; font-weight: 600; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.5px; }
.bm-chip-row { display: flex; gap: 6px; }
.bm-chip { padding: 4px 8px; font-size: 11px; background: rgba(255,255,255,0.05); border: 1px solid var(--border-glass); border-radius: 4px; cursor: pointer; transition: all 0.2s; color: var(--text-secondary); white-space: nowrap; }
.bm-chip:hover { background: rgba(255,255,255,0.1); color: var(--text-primary); }
.bm-chip.bm-chip-act { background: #eab30826; border-color: #eab30866; color: #fef08a; }
.bm-time-ctrls { display: flex; gap: 6px; align-items: center; }

.bm-canvas-wrap { position: relative; border-radius: var(--radius-md); overflow: hidden; border: 1px solid var(--border-glass); background: #060810; width: 100%; aspect-ratio: 560 / 380; }
.bm-canvas-wrap canvas { width: 100%; height: 100%; display: block; }
.bm-growth-meter { position: absolute; bottom: 10px; left: 10px; right: 10px; background: rgba(0,0,0,0.7); backdrop-filter: blur(4px); border: 1px solid var(--border-glass); padding: 8px 12px; border-radius: 6px; display: flex; align-items: center; gap: 10px; font-size: 11px; color: var(--text-muted); font-weight: 600; text-transform: uppercase; letter-spacing: 1px; }
.bm-meter-bg { flex: 1; height: 6px; background: rgba(255,255,255,0.1); border-radius: 100px; }
.bm-meter-fill { height: 100%; width: 0%; background: linear-gradient(90deg, #22c55e, #ef4444); border-radius: 100px; transition: width 0.3s; }

.bm-overlay { position: absolute; inset: 0; display: flex; align-items: center; justify-content: center; background: rgba(6,8,16,0.82); backdrop-filter: blur(4px); z-index: 10; }
.bm-start-card { text-align: center; padding: 24px; background: rgba(15,20,30,0.9); border: 1px solid var(--border-glass); border-radius: 12px; box-shadow: 0 10px 40px rgba(0,0,0,0.5); max-width: 320px; }
.bm-big-btn { display: inline-block; padding: 10px 24px; background: linear-gradient(135deg, #ca8a04, #eab308); color: #fff; font-family: 'Inter', sans-serif; font-size: 14px; font-weight: 600; border: none; border-radius: var(--radius-sm); cursor: pointer; transition: all var(--transition-fast); box-shadow: 0 4px 16px rgba(234,179,8,0.3); }
.bm-big-btn:hover { transform: translateY(-2px); box-shadow: 0 6px 24px rgba(234,179,8,0.45); }

.bm-desc-box { display: flex; align-items: flex-start; gap: 8px; padding: 10px 14px; background: rgba(15,20,30,0.5); border: 1px solid var(--border-glass); border-radius: var(--radius-sm); font-size: 13px; color: var(--text-secondary); line-height: 1.5; }
.bm-fb { padding: 8px 12px; border-radius: var(--radius-sm); font-size: 12px; font-weight: 500; animation: psFadeSlide 0.3s ease; }
.bm-fb.hidden { display: none; }
.bm-fb-success { background: rgba(34,197,94,0.15); border: 1px solid rgba(34,197,94,0.3); color: #4ade80; }
.bm-fb-error   { background: rgba(239,68,68,0.15);  border: 1px solid rgba(239,68,68,0.3);  color: #f87171; }

.bm-panel { display: flex; flex-direction: column; gap: 10px; overflow-y: auto; }
.bm-panel-sec { background: rgba(15,20,30,0.6); border: 1px solid var(--border-glass); border-radius: var(--radius-md); padding: 14px; }
.bm-panel-hd { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 1px; color: #eab308; margin-bottom: 10px; border-bottom: 1px solid var(--border-glass); padding-bottom: 6px; }
.bm-stat-row { display: flex; justify-content: space-between; font-size: 12px; margin-bottom: 6px; }
.bm-stat-row span { color: var(--text-muted); }
.bm-form-lbl { font-size: 11px; color: var(--text-muted); display: block; margin-bottom: 4px; margin-top: 8px; }
.bm-select { width: 100%; padding: 7px 10px; background: rgba(255,255,255,0.05); border: 1px solid var(--border-glass); border-radius: 6px; color: var(--text-primary); }
.bm-select option { background: #0f172a; }
.bm-obs-btn { width: 100%; padding: 8px; background: rgba(234,179,8,0.15); border: 1px solid rgba(234,179,8,0.3); border-radius: 6px; color: #eab308; cursor: pointer; transition: 0.2s; margin-top: 10px; }
.bm-obs-btn:hover { background: rgba(234,179,8,0.25); }
.bm-viva-btn { width: 100%; padding: 10px; background: linear-gradient(135deg, #a855f733, #d946ef33); border: 1px solid #a855f755; border-radius: var(--radius-sm); color: #d8b4fe; font-weight: 600; cursor: pointer; transition: 0.2s; margin-top: 10px; }
.bm-viva-btn:hover { background: linear-gradient(135deg, #a855f74d, #d946ef4d); transform: translateY(-1px); }

.bm-viva-ov { position: fixed; inset: 0; z-index: 999; display: flex; align-items: center; justify-content: center; background: rgba(0,0,0,0.8); backdrop-filter: blur(4px); }
.bm-viva-ov.hidden { display: none; }
.bm-viva-mo { background: #0b0f19; border: 1px solid var(--border-glass-hover); border-radius: 12px; width: 100%; max-width: 500px; padding: 20px; box-shadow: 0 20px 60px rgba(0,0,0,0.6); }
.bm-viva-hd { display: flex; border-bottom: 1px solid var(--border-glass); padding-bottom: 12px; margin-bottom: 16px; align-items: center; }
.bm-vclose { background: transparent; border: none; color: var(--text-muted); cursor: pointer; font-size: 16px; }
.bm-vclose:hover { color: #f87171; }
.bm-vopt { display: block; width: 100%; text-align: left; padding: 10px 14px; background: rgba(255,255,255,0.05); border: 1px solid var(--border-glass); border-radius: 6px; color: var(--text-secondary); cursor: pointer; transition: 0.2s; }
.bm-vopt:hover:not(:disabled) { background: rgba(255,255,255,0.1); color: var(--text-primary); border-color: var(--border-glass-hover); }

@media (max-width: 900px) {
  .bm-grid { grid-template-columns: 1fr; }
  .bm-sidebar { display: grid; grid-template-columns: repeat(2, 1fr); gap: 6px; }
  .bm-panel { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
}
@media (max-width: 600px) {
  .bm-sidebar { grid-template-columns: 1fr; }
  .bm-panel { grid-template-columns: 1fr; }
}

/* ============================================================
   LANDING HERO — Full-viewport welcome screen
   ============================================================ */
.landing-hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 100px 32px 80px;
  overflow: hidden;
  background: var(--bg-primary);
  transition: opacity 0.5s cubic-bezier(0.4, 0, 0.2, 1),
              max-height 0.5s cubic-bezier(0.4, 0, 0.2, 1) 0.3s,
              padding 0.5s cubic-bezier(0.4, 0, 0.2, 1) 0.3s,
              min-height 0.5s cubic-bezier(0.4, 0, 0.2, 1) 0.3s;
}

.landing-hero.landing-hero-dismissed {
  opacity: 0;
  min-height: 0;
  max-height: 0;
  padding: 0;
  pointer-events: none;
  overflow: hidden;
}

.landing-hero.landing-hero-hidden {
  display: none !important;
}

.landing-hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  overflow: hidden;
}

.landing-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(130px);
  opacity: 0.22;
}
.landing-orb-1 {
  width: 600px; height: 600px;
  background: var(--physics-primary);
  top: -150px; left: -120px;
  animation: landingOrb1 18s ease-in-out infinite;
}
.landing-orb-2 {
  width: 500px; height: 500px;
  background: #a855f7;
  top: 20%; right: -100px;
  animation: landingOrb2 22s ease-in-out infinite;
}
.landing-orb-3 {
  width: 550px; height: 550px;
  background: var(--biology-primary);
  bottom: -120px; left: 30%;
  animation: landingOrb3 20s ease-in-out infinite;
}

@keyframes landingOrb1 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(60px, 40px) scale(1.1); }
  66% { transform: translate(-30px, -20px) scale(0.95); }
}
@keyframes landingOrb2 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(-50px, 30px) scale(1.05); }
  66% { transform: translate(40px, -40px) scale(0.92); }
}
@keyframes landingOrb3 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(40px, -30px) scale(1.08); }
  66% { transform: translate(-40px, 20px) scale(0.96); }
}

.landing-grid-overlay {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 20%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, black 20%, transparent 75%);
}

.landing-hero-content {
  position: relative;
  z-index: 2;
  max-width: 720px;
  animation: landingContentIn 1s cubic-bezier(0.16, 1, 0.3, 1) both;
}

@keyframes landingContentIn {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.landing-badge {
  display: inline-block;
  padding: 7px 20px;
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.2);
  border-radius: 100px;
  font-size: 13px;
  color: var(--physics-primary);
  font-weight: 500;
  margin-bottom: 28px;
  letter-spacing: 0.3px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  animation: landingBadgeIn 1s 0.2s cubic-bezier(0.16, 1, 0.3, 1) both;
}
@keyframes landingBadgeIn {
  from { opacity: 0; transform: translateY(12px) scale(0.95); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

.landing-title {
  font-family: 'Space Grotesk', sans-serif;
  font-size: clamp(40px, 7vw, 72px);
  font-weight: 700;
  line-height: 1.05;
  color: var(--text-primary);
  margin-bottom: 24px;
  letter-spacing: -0.04em;
}

.landing-gradient {
  background: linear-gradient(135deg, #3b82f6 0%, #a855f7 40%, #f97316 70%, #22c55e 100%);
  background-size: 200% 200%;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: gradientShift 6s ease-in-out infinite;
}

@keyframes gradientShift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

.landing-desc {
  font-size: 17px;
  color: var(--text-secondary);
  line-height: 1.8;
  max-width: 580px;
  margin: 0 auto 40px;
  letter-spacing: 0;
}

.landing-cta-group {
  margin-bottom: 48px;
}

.landing-cta-btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 18px 42px;
  background: linear-gradient(135deg, #3b82f6, #2563eb);
  color: white;
  font-family: 'Space Grotesk', sans-serif;
  font-size: 17px;
  font-weight: 600;
  border: none;
  border-radius: 14px;
  cursor: pointer;
  transition: all var(--transition-smooth);
  box-shadow: 0 4px 24px rgba(59, 130, 246, 0.3), 0 0 0 0 rgba(59, 130, 246, 0.2);
  letter-spacing: -0.01em;
  position: relative;
  overflow: hidden;
}
.landing-cta-btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.15), transparent 60%);
  pointer-events: none;
}
.landing-cta-btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 36px rgba(59, 130, 246, 0.45), 0 0 0 4px rgba(59, 130, 246, 0.1);
}
.landing-cta-btn:active {
  transform: translateY(-1px);
}

.landing-cta-arrow {
  font-size: 20px;
  transition: transform var(--transition-fast);
}
.landing-cta-btn:hover .landing-cta-arrow {
  transform: translateX(4px);
}

.landing-cta-sub {
  margin-top: 14px;
  font-size: 13px;
  color: var(--text-muted);
  letter-spacing: 0.3px;
}

.landing-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  animation: landingPillsIn 1s 0.6s cubic-bezier(0.16, 1, 0.3, 1) both;
}
@keyframes landingPillsIn {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

.landing-pill {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 6px 14px;
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 100px;
  font-size: 13px;
  color: var(--text-secondary);
  font-weight: 500;
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  transition: all var(--transition-fast);
}
.landing-pill:hover {
  background: rgba(255,255,255,0.08);
  border-color: rgba(255,255,255,0.15);
  color: var(--text-primary);
  transform: translateY(-2px);
}

.landing-scroll-hint {
  position: absolute;
  bottom: 36px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  color: var(--text-muted);
  letter-spacing: 1px;
  text-transform: uppercase;
  font-weight: 500;
  transition: opacity 0.5s ease;
  z-index: 2;
}

.landing-scroll-arrow {
  font-size: 18px;
  animation: scrollBounce 2s ease-in-out infinite;
}

@keyframes scrollBounce {
  0%, 100% { transform: translateY(0); opacity: 1; }
  50% { transform: translateY(8px); opacity: 0.5; }
}

/* ============================================================
   FOOTER
   ============================================================ */
.site-footer {
  border-top: 1px solid var(--border-glass);
  background: rgba(5, 7, 12, 0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  padding: 48px 28px;
  text-align: center;
}

.footer-inner {
  max-width: var(--content-max-width);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 4px;
}
.footer-logo {
  font-size: 22px;
}
.footer-name {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 16px;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.footer-copy {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.5;
}

.footer-links {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-secondary);
}
.footer-sep {
  color: var(--text-muted);
}
.footer-link-item {
  color: var(--text-secondary);
  transition: color var(--transition-fast);
  cursor: default;
}
.footer-link-item:hover {
  color: var(--text-primary);
}