/* ==========================================================================
   shared-layout.css — Consolidated layout styles for navigation, search,
   simulation footer, and design tokens.
   
   This is the canonical source for design system styles shared across all pages.
   ========================================================================== */

/* ==========================================================================
   Import Inter font
   ========================================================================== */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

/* ==========================================================================
   Design Tokens (global CSS custom properties)
   ========================================================================== */
:root {
  /* Brand */
  --color-primary: #0891B2;
  --color-primary-hover: #0E7490;
  --color-primary-light: #ECFEFF;
  --color-secondary: #1E293B;
  --color-secondary-light: #F1F5F9;

  /* Accent */
  --color-accent: #F59E0B;
  --color-accent-light: #FEF3C7;
  --color-accent-hover: #D97706;

  /* Semantic */
  --color-success: #10B981;
  --color-success-light: #D1FAE5;
  --color-warning: #F59E0B;
  --color-warning-light: #FEF3C7;
  --color-danger: #EF4444;
  --color-danger-light: #FEE2E2;
  --color-info: #3B82F6;

  /* Surface & Background */
  --color-bg: #FAFBFC;
  --color-surface: #FFFFFF;
  --color-surface-raised: #FFFFFF;
  --color-surface-subtle: #F8FAFC;
  --color-border: #E2E8F0;
  --color-border-light: #F1F5F9;
  --color-border-focus: #0891B2;

  /* Text */
  --color-text-primary: #0F172A;
  --color-text-secondary: #475569;
  --color-text-tertiary: #94A3B8;
  --color-text-inverse: #FFFFFF;
  --color-text-link: #0891B2;

  /* Shadows */
  --shadow-xs: 0 1px 2px rgba(0,0,0,0.04);
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 6px -2px rgba(0,0,0,0.06), 0 2px 4px -2px rgba(0,0,0,0.04);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.06), 0 4px 6px -4px rgba(0,0,0,0.04);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.08), 0 8px 10px -6px rgba(0,0,0,0.04);
  --shadow-focus: 0 0 0 3px rgba(8,145,178,0.25);

  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-xl: 12px;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 200ms ease;
  --transition-slow: 300ms ease-in-out;

  /* Layout */
  --container-max: 1200px;
  --container-narrow: 800px;
  --header-height: 56px;
}

/* ==========================================================================
   Base / Typography
   ========================================================================== */
body {
  font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ==========================================================================
   Navigation (glass-morphism by default)
   ========================================================================== */
.site-nav {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  padding: 0.6rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
  border-bottom: 1px solid var(--color-border);
  box-shadow: none;
  position: sticky;
  top: 0;
  z-index: 1000;
}

.site-nav-brand {
  color: var(--color-text-primary);
  font-weight: 700;
  font-size: 1.1rem;
  text-decoration: none;
  white-space: nowrap;
  display: flex;
  align-items: center;
  transition: color var(--transition-fast);
}

.site-nav-brand:hover {
  color: var(--color-primary);
}

.site-nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 0.4rem 0.6rem;
  cursor: pointer;
  color: var(--color-text-primary);
  transition: background-color var(--transition-base);
}

.site-nav-toggle:hover {
  background-color: var(--color-secondary-light);
}

.site-nav-toggle svg {
  width: 20px;
  height: 20px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.site-nav-links {
  display: flex;
  gap: 0.25rem;
  align-items: center;
  flex-wrap: wrap;
}

.site-nav-links a {
  color: var(--color-text-secondary);
  text-decoration: none;
  padding: 0.4rem 0.8rem;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  font-weight: 500;
  transition: background-color var(--transition-fast), color var(--transition-fast);
  white-space: nowrap;
}

.site-nav-links a:hover,
.site-nav-links a[aria-current="page"] {
  background-color: var(--color-secondary-light);
  color: var(--color-text-primary);
}

.site-nav-links a:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.site-locale-switcher {
  margin-left: 0.5rem;
  display: flex;
  align-items: center;
}

.site-locale-switcher a {
  color: var(--color-text-secondary);
  text-decoration: none;
  padding: 0.4rem 0.6rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 0.85rem;
}

.site-locale-switcher a:hover {
  background-color: var(--color-secondary-light);
}

.site-locale-switcher a[aria-current] {
  background-color: var(--color-secondary-light);
  color: var(--color-primary);
}

@media (max-width: 992px) {
  .site-nav-toggle {
    display: block;
  }

  .site-nav-links {
    flex-basis: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 0.2rem;
    max-height: 0;
    opacity: 0;
    visibility: hidden;
    overflow: hidden;
    transition: opacity 0.3s ease-in-out, max-height 0.3s ease-in-out, visibility 0s 0.3s;
    border-top: none;
    padding-top: 0;
    margin-top: 0;
  }

  .site-nav-links.open {
    max-height: 600px;
    opacity: 1;
    visibility: visible;
    transition: opacity 0.3s ease-in-out, max-height 0.3s ease-in-out, visibility 0s 0s;
    border-top: 1px solid var(--color-border-light);
    padding-top: 0.5rem;
    margin-top: 0.5rem;
  }

  .site-nav-links a {
    padding: 0.75rem 1rem;
  }
}

/* ==========================================================================
   Breadcrumbs (in default layout)
   ========================================================================== */
.breadcrumb-nav ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 0;
  margin: 0 0 1.5rem;
  font-size: 0.875rem;
}

.breadcrumb-nav li {
  display: flex;
  align-items: center;
}

.breadcrumb-nav li:not(:last-child)::after {
  content: '/';
  margin-left: 0.5rem;
  color: var(--color-text-tertiary);
}

.breadcrumb-nav a {
  color: var(--color-text-link);
  text-decoration: none;
}

.breadcrumb-nav a:hover {
  text-decoration: underline;
}

.breadcrumb-nav li[aria-current="page"] {
  color: var(--color-text-secondary);
}

/* ==========================================================================
   Main content area overrides for Primer theme
   ========================================================================== */
.markdown-body {
  font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
}

.markdown-body h1,
.markdown-body h2,
.markdown-body h3,
.markdown-body h4 {
  font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  color: var(--color-text-primary);
}

.markdown-body a {
  color: var(--color-text-link);
}

.markdown-body img {
  border-radius: var(--radius-lg);
}

/* ==========================================================================
   Search (updated for design system)
   ========================================================================== */
.search-container {
  position: relative;
  margin: 0 auto 2rem;
  max-width: 600px;
}

.search-input {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  font-size: 1rem;
  font-family: 'Inter', system-ui, sans-serif;
  background: var(--color-surface);
  box-shadow: var(--shadow-xs);
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.search-input:focus-visible {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-focus);
}

.search-results {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  margin-top: 0.5rem;
  max-height: 400px;
  overflow-y: auto;
  z-index: 50;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
}

.search-results[hidden] {
  display: none;
}

.search-results-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.search-result-item {
  border-bottom: 1px solid var(--color-border-light);
}

.search-result-item:last-child {
  border-bottom: 0;
}

.search-result-link {
  display: block;
  padding: 0.75rem 1rem;
  text-decoration: none;
  color: var(--color-text-primary);
  transition: background-color var(--transition-fast);
}

.search-result-link:hover,
.search-result-item.is-active .search-result-link {
  background-color: var(--color-secondary-light);
}

.search-result-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.search-result-title {
  font-weight: 600;
  font-size: 0.9rem;
}

.search-result-badge {
  background-color: var(--color-primary-light);
  color: var(--color-primary);
  padding: 0.2rem 0.5rem;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 600;
  flex-shrink: 0;
}

.search-result-empty {
  padding: 1rem;
  color: var(--color-text-tertiary);
  text-align: center;
}

/* ==========================================================================
   Card grid (used in simulations index)
   ========================================================================== */
.results-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
}

.sim-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xs);
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: inherit;
  transition: box-shadow var(--transition-base), transform var(--transition-base);
  overflow: hidden;
  height: 100%;
}

.sim-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.sim-card-image {
  width: 100%;
  height: 168px;
  object-fit: cover;
}

.sim-card-image.is-fallback {
  object-fit: contain;
  padding: 1rem;
}

.sim-card-content {
  padding: 1.25rem;
  flex-grow: 1;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.sim-card-title {
  font-weight: 600;
  font-size: 1rem;
  margin-bottom: 0.5rem;
  color: var(--color-text-primary);
}

.sim-card-desc {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  margin-bottom: 1rem;
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.sim-card-badge {
  align-self: flex-start;
  background-color: var(--color-primary-light);
  color: var(--color-primary);
  padding: 0.25rem 0.5rem;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 600;
}

.no-results {
  text-align: center;
  padding: 3rem;
  color: var(--color-text-tertiary);
  font-size: 1.1rem;
  grid-column: 1 / -1;
}

#results-count {
  margin-bottom: 1rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  font-size: 0.9rem;
}

/* ==========================================================================
   Simulations index page search controls
   ========================================================================== */
.search-page-header {
  text-align: center;
  margin-bottom: 2rem;
}

.search-page-header h1 {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--color-text-primary);
  margin-bottom: 0.5rem;
}

.search-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
  margin-bottom: 2rem;
  align-items: center;
}

.search-input-large {
  flex-grow: 1;
  max-width: 500px;
  padding: 0.75rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  font-size: 1rem;
  font-family: 'Inter', system-ui, sans-serif;
  outline: none;
  background: var(--color-surface);
  box-shadow: var(--shadow-xs);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.search-input-large:focus {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-focus);
}

.filter-select {
  padding: 0.75rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  font-size: 0.9rem;
  font-family: 'Inter', system-ui, sans-serif;
  outline: none;
  background-color: var(--color-surface);
  box-shadow: var(--shadow-xs);
  cursor: pointer;
  color: var(--color-text-primary);
  transition: border-color var(--transition-fast);
}

.filter-select:focus {
  border-color: var(--color-primary);
}

/* ==========================================================================
   Article cards
   ========================================================================== */
.article-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: 1.5rem;
  margin-bottom: 1rem;
  box-shadow: var(--shadow-xs);
  transition: box-shadow var(--transition-base);
}

.article-card:hover {
  box-shadow: var(--shadow-md);
}

.article-card h2 {
  margin-top: 0;
  font-size: 1.15rem;
  font-weight: 600;
}

.article-card h2 a {
  color: var(--color-text-primary);
  text-decoration: none;
}

.article-card h2 a:hover {
  color: var(--color-primary);
}

.article-card .article-date {
  color: var(--color-text-tertiary);
  font-size: 0.875rem;
  margin: 0.25rem 0 0.5rem;
}

.article-card .article-desc {
  margin: 0;
  color: var(--color-text-secondary);
  font-size: 0.9375rem;
  line-height: 1.6;
}

.article-card .article-link {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-text-link);
  text-decoration: none;
  display: inline-block;
  margin-top: 0.75rem;
  transition: color var(--transition-fast);
}

.article-card .article-link:hover {
  color: var(--color-primary-hover);
}

/* ==========================================================================
   Button styles (shared)
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: 'Inter', system-ui, sans-serif;
  font-weight: 500;
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none !important;
  white-space: nowrap;
}

.btn-md {
  font-size: 14px;
  padding: 8px 16px;
  min-height: 40px;
}

.btn-lg {
  font-size: 16px;
  padding: 12px 24px;
  min-height: 48px;
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-text-inverse) !important;
  border-color: var(--color-primary);
  box-shadow: var(--shadow-xs);
}

.btn-primary:hover {
  background: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
}

.btn-ghost {
  background: transparent;
  color: var(--color-text-primary) !important;
  border-color: var(--color-border);
}

.btn-ghost:hover {
  background: var(--color-secondary-light);
}

/* ==========================================================================
   Section / Container helpers (for non-hero pages)
   ========================================================================== */
.section {
  padding: 48px 0;
}

.section .container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
}

.section-header {
  text-align: center;
  margin-bottom: 32px;
}

.section-header h2 {
  font-size: 1.5rem;
  font-weight: 600;
  letter-spacing: -0.015em;
  color: var(--color-text-primary);
  margin-bottom: 8px;
}

.section-header p {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  max-width: 560px;
  margin: 0 auto;
}

/* ==========================================================================
   Simulation Footer (formerly simulation-footer.css)
   ========================================================================== */
#sim-footer-container {
  position: fixed;
  left: 1rem;
  bottom: 1rem;
  z-index: 50;
  display: flex;
  align-items: center;
  width: fit-content;
  max-width: calc(100vw - 2rem);
  padding: 0.25rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-full);
  background: rgba(255, 255, 255, 0.85);
  color: var(--color-text-secondary);
  font: 500 0.875rem/1.4 'Inter', system-ui, sans-serif;
  box-shadow: 0 10px 25px -12px rgba(15, 23, 42, 0.6);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: background-color var(--transition-base), box-shadow var(--transition-base);
}

#sim-footer-container:hover {
  background: rgba(255, 255, 255, 0.95);
  box-shadow: 0 14px 30px -16px rgba(15, 23, 42, 0.7);
}

#sim-footer-toggle,
#sim-footer-actions > .sim-footer-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  width: 2.5rem;
  height: 2.5rem;
  padding: 0;
  border: 0;
  border-radius: var(--radius-full);
  background: transparent;
  transition: background-color var(--transition-base), color var(--transition-base), box-shadow var(--transition-base);
}

#sim-footer-toggle {
  color: var(--color-text-tertiary);
}

#sim-footer-toggle:hover {
  background: var(--color-border);
}

#sim-footer-toggle:focus-visible,
#sim-footer-actions > .sim-footer-action:focus-visible {
  outline: none;
  box-shadow: 0 0 0 2px #ffffff, 0 0 0 4px var(--color-primary);
}

#sim-footer-toggle svg,
#sim-footer-actions > .sim-footer-action svg {
  width: 1rem;
  height: 1rem;
}

#sim-footer-breadcrumbs {
  display: flex;
  align-items: center;
  min-width: 0;
  max-width: min(48rem, calc(100vw - 10rem));
  overflow: hidden;
  white-space: nowrap;
  opacity: 1;
  padding-right: 0.5rem;
  transition: max-width 0.3s ease, opacity 0.2s ease, padding-right 0.3s ease;
}

#sim-footer-breadcrumbs.sim-footer-breadcrumbs--collapsed {
  max-width: 0;
  opacity: 0;
  padding-right: 0;
}

#sim-footer-breadcrumbs a,
#sim-footer-breadcrumbs span {
  flex-shrink: 0;
}

.sim-footer-link {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.sim-footer-link:hover {
  color: var(--color-primary-hover);
}

.sim-footer-link--home {
  display: inline-flex;
  align-items: center;
  font-weight: 600;
}

.sim-footer-home-icon {
  width: 1rem;
  height: 1rem;
  margin-right: 0.25rem;
}

.sim-footer-separator {
  margin: 0 0.5rem;
  color: var(--color-text-tertiary);
}

.sim-footer-current {
  color: var(--color-text-tertiary);
  font-weight: 600;
}

#sim-footer-actions {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  gap: 0.125rem;
  margin-left: 0.25rem;
  padding-left: 0.25rem;
  border-left: 1px solid var(--color-border);
  transition: margin-left 0.3s ease, padding-left 0.3s ease, border-color var(--transition-base);
}

#sim-footer-container.sim-footer-container--collapsed #sim-footer-actions {
  margin-left: 0;
  padding-left: 0;
  border-left-color: transparent;
}

#sim-footer-actions > .sim-footer-action {
  color: inherit;
}

#sim-share-btn {
  color: var(--color-primary);
}

#sim-share-btn:hover {
  background: var(--color-primary-light);
}

#sim-reset-btn {
  color: var(--color-accent-hover);
}

#sim-reset-btn:hover {
  background: var(--color-accent-light);
}

#sim-task-btn {
  color: var(--color-success);
  text-decoration: none;
}

#sim-task-btn:hover {
  background: var(--color-success-light);
}

@media (max-width: 640px) {
  #sim-footer-container {
    left: 0.75rem;
    bottom: 0.75rem;
    max-width: calc(100vw - 1.5rem);
  }

  #sim-footer-breadcrumbs {
    max-width: calc(100vw - 8.5rem);
  }
}

/* ==========================================================================
   Mobile Responsive — Global touch-friendly & overflow-safe defaults
   ========================================================================== */

/* ── Touch-friendly interactive elements (min 44px tap target) ── */
@media (hover: none) and (pointer: coarse), (max-width: 768px) {
  .site-nav-links a {
    min-height: 44px;
    display: flex;
    align-items: center;
  }

  .site-nav-toggle {
    min-width: 44px;
    min-height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  button,
  .btn,
  .teacher-btn,
  .dashboard-btn,
  .sim-card,
  .site-nav-links a,
  .site-locale-switcher a,
  .pagination a,
  .results-grid a {
    min-height: 44px;
  }

  .teacher-tab,
  .dashboard-tab {
    min-height: 44px;
    display: flex;
    align-items: center;
  }

  input[type="range"] {
    height: 44px;
    margin: 0;
    padding: 0;
  }

  input[type="range"]::-webkit-slider-thumb {
    width: 28px;
    height: 28px;
    -webkit-appearance: none;
    appearance: none;
    background: var(--color-primary, #0891B2);
    border-radius: 50%;
    cursor: pointer;
    border: 2px solid #fff;
    box-shadow: 0 2px 6px rgba(0,0,0,0.2);
  }

  input[type="range"]::-moz-range-thumb {
    width: 28px;
    height: 28px;
    background: var(--color-primary, #0891B2);
    border-radius: 50%;
    cursor: pointer;
    border: 2px solid #fff;
    box-shadow: 0 2px 6px rgba(0,0,0,0.2);
  }
}

/* ── No horizontal overflow at any viewport ── */
html {
  overflow-x: hidden;
}

body {
  overflow-x: hidden;
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
}

img,
canvas,
svg,
video,
iframe {
  max-width: 100%;
  height: auto;
}

table {
  display: block;
  max-width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

/* ── Mobile: 375px ── */
@media (max-width: 480px) {
  body {
    font-size: 14px;
  }

  .markdown-body h1 {
    font-size: 1.5rem !important;
  }

  .markdown-body h2 {
    font-size: 1.3rem !important;
  }

  .markdown-body {
    padding: 0.5rem !important;
  }

  .container-lg {
    padding-left: 0.75rem !important;
    padding-right: 0.75rem !important;
  }

  .breadcrumb-nav ol {
    font-size: 0.75rem;
    gap: 0.3rem;
    margin-bottom: 0.75rem;
  }

  .breadcrumb-nav li:not(:last-child)::after {
    margin-left: 0.3rem;
  }

  .results-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .sim-card-image {
    height: 140px;
  }

  .search-page-header h1 {
    font-size: 1.5rem;
  }

  .search-container {
    max-width: 100%;
    margin-left: 0.5rem;
    margin-right: 0.5rem;
  }

  .search-results {
    max-height: 60vh;
  }

  .search-result-row {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.3rem;
  }

  .category-grid {
    grid-template-columns: 1fr;
  }

  .stats-row {
    gap: 1.5rem;
  }

  .stat-item {
    min-width: 80px;
  }

  .stat-value {
    font-size: 2rem;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .steps-grid {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 2.5rem 0;
  }

  .section-title {
    font-size: 1.5rem;
  }

  .hero {
    padding: 3rem 0 2rem;
  }

  .hero-title {
    font-size: 1.75rem;
  }

  .hero-subtitle {
    font-size: 0.95rem;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-actions .btn {
    width: 100%;
    justify-content: center;
  }

  .onboarding-banner-inner {
    flex-wrap: wrap;
    font-size: 0.8rem;
  }
}

/* ── Tablet: 768px ── */
@media (max-width: 768px) {
  .results-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .steps-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .hero-title {
    font-size: 2rem;
  }

  .category-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .teacher-stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .teacher-tabs {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }

  .teacher-tabs::-webkit-scrollbar {
    display: none;
  }

  .teacher-tab {
    white-space: nowrap;
    flex-shrink: 0;
  }
}

/* ── Simulation page overrides for mobile ── */
@media (max-width: 768px) {
  .simulation-layout-main {
    padding: 0.5rem;
  }

  .simulation-layout-main .max-w-6xl {
    padding-left: 0;
    padding-right: 0;
  }

  .simulation-layout-main [class*="grid-cols-"] {
    gap: 1rem;
  }

  .simulation-layout-main .bg-white,
  .simulation-layout-main .bg-gray-50,
  .simulation-layout-main .control-panel,
  .simulation-layout-main .data-panel {
    padding: 0.75rem !important;
  }

  .simulation-layout-main canvas {
    max-width: 100%;
    height: auto !important;
  }

  .simulation-layout-main .grid .space-y-4 > div {
    padding: 0.5rem !important;
  }

  /* Sim action buttons: stack vertically on mobile, keep min 44px */
  .simulation-layout-main .flex.space-x-2,
  .simulation-layout-main .flex.space-x-4 {
    flex-direction: column;
    gap: 0.5rem;
  }

  .simulation-layout-main .flex.space-x-2 > *,
  .simulation-layout-main .flex.space-x-4 > * {
    width: 100%;
    min-height: 44px;
  }

  .simulation-layout-main .flex.space-x-2 .flex-1,
  .simulation-layout-main .flex.space-x-4 .flex-1 {
    flex: none;
    width: 100%;
  }

  .simulation-layout-main input[type="range"] {
    height: 44px;
  }

  /* Share button mobile positioning */
  .sim-share-btn {
    bottom: 0.75rem;
    right: 0.75rem;
    padding: 0.4rem 0.75rem;
    font-size: 0.75rem;
  }

  /* First-visit tip mobile */
  #sim-first-tip {
    bottom: 3.5rem !important;
    right: 0.5rem !important;
    max-width: calc(100vw - 1rem) !important;
    font-size: 0.78rem !important;
  }
}

@media (max-width: 480px) {
  .simulation-layout-main h1 {
    font-size: 1.35rem !important;
  }

  .simulation-layout-main h2 {
    font-size: 1.1rem !important;
  }

  .simulation-layout-footer {
    padding: 0.5rem 0.75rem;
    font-size: 0.75rem;
  }
}