/* ============================================================
   style.css — Nuclear Energy Explorer Design System
   ============================================================ */

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

:root {
  --navy: #0f172a;
  --navy-light: #1e293b;
  --blue: #2563eb;
  --blue-light: #3b82f6;
  --green: #059669;
  --green-light: #10b981;
  --amber: #d97706;
  --amber-light: #f59e0b;
  --purple: #7c3aed;
  --purple-light: #8b5cf6;
  --red: #dc2626;
  --red-light: #ef4444;
  --slate: #64748b;
  --slate-light: #94a3b8;
  --white: #ffffff;
  --off-white: #f8fafc;
  --gray-100: #f1f5f9;
  --gray-200: #e2e8f0;
  --gray-300: #cbd5e1;
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.07), 0 2px 4px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);
  --transition: 0.2s ease;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--off-white);
  color: var(--navy);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* --- Header --- */
.site-header {
  background: var(--navy);
  color: var(--white);
  padding: 24px 0;
  border-bottom: 3px solid var(--blue);
}

.header-inner {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.5rem;
  font-weight: 700;
}

.logo-icon {
  font-size: 1.8rem;
}

.logo-sg {
  color: var(--blue-light);
  font-weight: 600;
}

.header-subtitle {
  font-size: 0.875rem;
  color: var(--slate-light);
  margin-top: 2px;
}

/* --- Navigation --- */
.section-nav {
  background: var(--white);
  border-bottom: 1px solid var(--gray-200);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow);
}

.nav-inner {
  display: flex;
  gap: 4px;
  overflow-x: auto;
  padding: 8px 0;
  -webkit-overflow-scrolling: touch;
}

.nav-btn {
  background: none;
  border: 2px solid transparent;
  padding: 10px 20px;
  font-family: inherit;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--slate);
  cursor: pointer;
  border-radius: var(--radius-sm);
  white-space: nowrap;
  transition: all var(--transition);
}

.nav-btn:hover {
  color: var(--blue);
  background: var(--gray-100);
}

.nav-btn.active {
  color: var(--blue);
  background: #eff6ff;
  border-color: var(--blue);
}

/* --- Panels --- */
.main-content {
  padding: 32px 24px;
}

.panel {
  background: var(--white);
  border-radius: var(--radius);
  padding: 32px;
  box-shadow: var(--shadow-md);
  margin-bottom: 24px;
}

.panel.hidden {
  display: none;
}

.section-title {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--navy);
  margin-bottom: 8px;
}

.section-desc {
  color: var(--slate);
  font-size: 0.95rem;
  margin-bottom: 28px;
  max-width: 700px;
}

.subsection-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--navy-light);
  margin: 28px 0 16px;
}

/* --- Controls --- */
.controls-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-bottom: 8px;
}

.control-card {
  background: var(--gray-100);
  padding: 20px;
  border-radius: var(--radius-sm);
}

.control-label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--slate);
  margin-bottom: 12px;
}

.slider-row {
  display: flex;
  align-items: center;
  gap: 16px;
}

.slider-row input[type="range"] {
  flex: 1;
  -webkit-appearance: none;
  appearance: none;
  height: 6px;
  background: var(--gray-300);
  border-radius: 3px;
  outline: none;
}

.slider-row input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  background: var(--blue);
  border-radius: 50%;
  cursor: pointer;
  box-shadow: 0 2px 4px rgba(37,99,235,0.3);
}

.slider-value {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--blue);
  min-width: 80px;
  text-align: right;
}

/* --- Industry Cards --- */
.industry-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  margin-bottom: 24px;
}

.industry-card {
  background: var(--gray-100);
  border: 2px solid var(--gray-200);
  border-radius: var(--radius-sm);
  padding: 16px;
  cursor: pointer;
  transition: all var(--transition);
  text-align: center;
}

.industry-card.active {
  border-color: var(--blue);
  background: #eff6ff;
}

.industry-card:hover {
  border-color: var(--blue-light);
}

.industry-icon {
  font-size: 2rem;
  display: block;
  margin-bottom: 8px;
}

.industry-name {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--navy);
  margin-bottom: 4px;
}

.industry-range {
  font-size: 0.7rem;
  color: var(--slate);
  margin-bottom: 10px;
}

.industry-stepper {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.stepper-btn {
  width: 28px;
  height: 28px;
  border: 1px solid var(--gray-300);
  background: var(--white);
  border-radius: 6px;
  font-size: 1rem;
  font-weight: 700;
  color: var(--navy);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
}

.stepper-btn:hover {
  background: var(--blue);
  color: var(--white);
  border-color: var(--blue);
}

.stepper-count {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--blue);
  min-width: 24px;
  text-align: center;
}

/* --- Summary Bar --- */
.summary-bar {
  background: var(--navy);
  color: var(--white);
  border-radius: var(--radius-sm);
  padding: 20px 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 32px;
  margin-bottom: 24px;
}

.summary-item {
  text-align: center;
}

.summary-value {
  font-size: 1.75rem;
  font-weight: 800;
  display: block;
}

.summary-label {
  font-size: 0.75rem;
  color: var(--slate-light);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.summary-value.green { color: var(--green-light); }
.summary-value.amber { color: var(--amber-light); }
.summary-value.blue { color: var(--blue-light); }
.summary-value.purple { color: var(--purple-light); }

/* --- Chart --- */
.chart-container {
  position: relative;
  width: 100%;
  max-height: 400px;
  margin-top: 16px;
}

.chart-container canvas {
  width: 100% !important;
  max-height: 400px;
}

/* --- Reactor Section --- */
.reactor-categories {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.reactor-category {
  margin-bottom: 8px;
}

.category-header {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 6px 14px;
  border-radius: 20px;
  display: inline-block;
  margin-bottom: 12px;
}

.reactor-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 12px;
}

.reactor-card {
  background: var(--gray-100);
  border: 2px solid var(--gray-200);
  border-radius: var(--radius-sm);
  padding: 16px;
  cursor: pointer;
  transition: all var(--transition);
}

.reactor-card.selected {
  border-color: var(--blue);
  background: #eff6ff;
  box-shadow: var(--shadow);
}

.reactor-card:hover {
  border-color: var(--blue-light);
}

.reactor-card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
}

.reactor-info-btn {
  background: var(--gray-200);
  border: none;
  border-radius: 50%;
  width: 28px;
  height: 28px;
  font-size: 0.85rem;
  cursor: pointer;
  color: var(--slate);
  flex-shrink: 0;
  transition: all var(--transition);
  line-height: 28px;
  text-align: center;
  padding: 0;
}
.reactor-info-btn:hover { background: var(--blue-light); color: var(--white); }
.reactor-info-btn.active { background: var(--blue); color: var(--white); }

.reactor-card-name {
  font-weight: 700;
  font-size: 0.95rem;
  margin-bottom: 4px;
}

.reactor-card-power {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--blue);
  margin-bottom: 6px;
}

.reactor-card-desc {
  font-size: 0.75rem;
  color: var(--slate);
  margin-bottom: 12px;
}

.reactor-card-type {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  padding: 2px 8px;
  border-radius: 4px;
  display: inline-block;
}

.type-fission { background: #fef3c7; color: #92400e; }
.type-fusion { background: #ede9fe; color: #5b21b6; }

/* Reactor profile panel */
.reactor-profile {
  display: none;
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px solid var(--gray-200);
}
.reactor-profile.open { display: block; }

.profile-section {
  margin-bottom: 12px;
}
.profile-section h4 {
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--navy);
  margin-bottom: 6px;
}
.profile-section p {
  font-size: 0.8rem;
  color: var(--navy);
  line-height: 1.5;
}
.profile-section ul {
  list-style: none;
  padding: 0;
}
.profile-section ul li {
  font-size: 0.8rem;
  color: var(--navy);
  line-height: 1.5;
  padding-left: 16px;
  position: relative;
  margin-bottom: 4px;
}
.profile-section ul li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--green);
  font-weight: 700;
}

.profile-waste {
  background: var(--gray-100);
  border-radius: var(--radius-sm);
  padding: 10px;
}
.reactor-card.selected .profile-waste {
  background: #e0edff;
}
.profile-waste-stats {
  display: flex;
  gap: 16px;
  margin-top: 8px;
}
.waste-stat {
  font-size: 0.75rem;
  color: var(--slate);
}
.waste-stat strong {
  color: var(--amber);
  font-size: 0.9rem;
}

.profile-safety-link {
  display: inline-block;
  margin-top: 4px;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--blue);
  text-decoration: none;
  transition: color var(--transition);
}
.profile-safety-link:hover { color: var(--blue-light); text-decoration: underline; }

/* Reactor count stepper */
.reactor-count-row {
  margin-top: 10px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.reactor-stepper {
  display: flex;
  align-items: center;
  gap: 8px;
}

.reactor-count-mw {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--amber);
  white-space: nowrap;
}

/* Reactor summary */
.reactor-summary {
  background: var(--navy);
  color: var(--white);
  border-radius: var(--radius-sm);
  padding: 24px;
  margin-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 32px;
}

/* Reactor pictograph */
.reactor-pictograph {
  margin-top: 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 16px;
  background: var(--gray-100);
  border-radius: var(--radius-sm);
}

.reactor-icon-unit {
  width: 32px;
  height: 32px;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--white);
}

/* --- Land Section --- */
.land-controls {
  margin-bottom: 24px;
}

.toggle-label {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
  font-size: 0.95rem;
  font-weight: 500;
}

.toggle-label input[type="checkbox"] {
  display: none;
}

.toggle-slider {
  width: 48px;
  height: 26px;
  background: var(--gray-300);
  border-radius: 13px;
  position: relative;
  transition: all var(--transition);
}

.toggle-slider::after {
  content: '';
  position: absolute;
  width: 20px;
  height: 20px;
  background: var(--white);
  border-radius: 50%;
  top: 3px;
  left: 3px;
  transition: all var(--transition);
  box-shadow: 0 1px 3px rgba(0,0,0,0.2);
}

.toggle-label input:checked + .toggle-slider {
  background: var(--green);
}

.toggle-label input:checked + .toggle-slider::after {
  transform: translateX(22px);
}

.land-comparison {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  margin-bottom: 32px;
}

.land-block {
  text-align: center;
}

.land-block-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 16px;
}

.land-rect-container {
  position: relative;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  min-height: 250px;
  padding: 16px;
}

.land-rect {
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  transition: all 0.5s ease;
  position: relative;
}

.land-rect-label {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--white);
}

.land-rect-sublabel {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.8);
  margin-top: 4px;
}

.landmark-comparisons {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px;
}

.landmark-card {
  background: var(--gray-100);
  border-radius: var(--radius-sm);
  padding: 16px;
  text-align: center;
}

.landmark-value {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--blue);
}

.landmark-name {
  font-size: 0.8rem;
  color: var(--slate);
  margin-top: 4px;
}

/* --- Waste Section --- */
.waste-cubes-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  margin-bottom: 32px;
}

.waste-cube-block {
  text-align: center;
}

.waste-cube-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 20px;
}

.cube-scene {
  width: 200px;
  height: 200px;
  margin: 0 auto 16px;
  perspective: 600px;
}

.cube {
  width: 100%;
  height: 100%;
  position: relative;
  transform-style: preserve-3d;
  transform: rotateX(-20deg) rotateY(30deg);
  transition: all 0.6s ease;
}

.cube-face {
  position: absolute;
  border: 1px solid rgba(255,255,255,0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: var(--white);
  font-size: 0.85rem;
  backface-visibility: visible;
}

.cube-face.front  { transform: rotateY(0deg); }
.cube-face.back   { transform: rotateY(180deg); }
.cube-face.right  { transform: rotateY(90deg); }
.cube-face.left   { transform: rotateY(-90deg); }
.cube-face.top    { transform: rotateX(90deg); }
.cube-face.bottom { transform: rotateX(-90deg); }

.waste-stats {
  font-size: 0.85rem;
  color: var(--slate);
  margin-top: 8px;
}

.waste-stats strong {
  color: var(--navy);
}

/* Cask counter */
.cask-counter {
  background: var(--gray-100);
  border-radius: var(--radius-sm);
  padding: 20px;
  margin-bottom: 24px;
}

.cask-counter-title {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--slate);
  margin-bottom: 12px;
}

.cask-icons {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.cask-icon {
  width: 36px;
  height: 44px;
  background: var(--amber);
  border-radius: 4px 4px 6px 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.65rem;
  font-weight: 700;
  color: var(--white);
  position: relative;
}

.cask-icon::before {
  content: '';
  position: absolute;
  top: -3px;
  left: 25%;
  right: 25%;
  height: 6px;
  background: var(--amber-light);
  border-radius: 3px;
}

/* --- Carbon Section --- */
.carbon-dashboard {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 24px;
}

.carbon-stat-card {
  background: var(--gray-100);
  border-radius: var(--radius-sm);
  padding: 20px;
  text-align: center;
  border: 2px solid var(--gray-200);
}

.carbon-stat-card.negative {
  border-color: var(--green);
  background: #ecfdf5;
}

.carbon-stat-value {
  font-size: 2rem;
  font-weight: 800;
  display: block;
}

.carbon-stat-label {
  font-size: 0.8rem;
  color: var(--slate);
  margin-top: 4px;
}

.carbon-stat-value.green { color: var(--green); }
.carbon-stat-value.red { color: var(--red); }
.carbon-stat-value.blue { color: var(--blue); }

/* --- Footer --- */
.site-footer {
  background: var(--navy);
  color: var(--slate-light);
  text-align: center;
  padding: 24px;
  font-size: 0.8rem;
  margin-top: 48px;
}

.footer-note {
  font-size: 0.7rem;
  margin-top: 4px;
  color: var(--slate);
}

.site-footer .bmc-banner {
  display: inline-block;
  margin-top: 16px;
  padding: 10px 24px;
  background-color: #ffdd00;
  color: #000;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 700;
  font-size: 0.9rem;
  letter-spacing: 0.02em;
  transition: opacity 0.2s;
}
.site-footer .bmc-banner:hover { opacity: 0.85; }

/* --- Responsive --- */
@media (max-width: 1024px) {
  .controls-grid {
    grid-template-columns: 1fr;
  }
  .industry-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .land-comparison {
    grid-template-columns: 1fr;
  }
  .waste-cubes-row {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  .carbon-dashboard {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 0 16px;
  }
  .panel {
    padding: 20px;
  }
  .main-content {
    padding: 16px;
  }
  .industry-grid {
    grid-template-columns: 1fr 1fr;
  }
  .reactor-cards {
    grid-template-columns: 1fr;
  }
  .summary-bar {
    gap: 16px;
  }
  .summary-value {
    font-size: 1.3rem;
  }
  .carbon-dashboard {
    grid-template-columns: 1fr;
  }
  .nav-inner {
    gap: 2px;
  }
  .nav-btn {
    padding: 8px 14px;
    font-size: 0.8rem;
  }
  .landmark-comparisons {
    grid-template-columns: 1fr 1fr;
  }
}