/* =============================================================
   Anatomie d'un ordinateur — Design system partagé
   ============================================================= */

:root {
  /* Palette héritée de la heatmap V1 */
  --bg: #0e0d0b;
  --bg-alt: #151411;
  --bg-card: #1c1a16;
  --bg-elev: #211e19;
  --ink: #f4efe4;
  --ink-dim: #a8a196;
  --ink-faint: #807b6f;
  --paper: #1c1a16;
  --line: #2a2722;
  --line-soft: #1f1d19;
  --accent: #f0b742;
  --accent-soft: #c6823a;
  --accent-deep: #7a5320;

  /* Couches OSI (cohérence avec V1) */
  --c-l1: #d47148;
  --c-l2: #e09a3a;
  --c-l3: #c5a548;
  --c-l4: #8fa847;
  --c-l5: #4f9e8a;
  --c-l6: #5688b0;
  --c-l7: #8169a8;
  --c-hx: #a05668;

  /* Catégories encyclopédie */
  --cat-materiel: #d47148;
  --cat-logiciel: #8169a8;
  --cat-reseaux: #5688b0;
  --cat-web: #4f9e8a;
  --cat-securite: #a05668;
  --cat-langages: #c5a548;
  --cat-histoire: #e09a3a;
  --cat-ia: #8fa847;

  /* Typographie */
  --font-serif: 'Fraunces', Georgia, serif;
  --font-sans: 'Inter Tight', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, monospace;

  /* Espacements */
  --gap-xs: 6px;
  --gap-sm: 12px;
  --gap-md: 20px;
  --gap-lg: 36px;
  --gap-xl: 60px;

  /* Rayons */
  --r-xs: 4px;
  --r-sm: 6px;
  --r-md: 12px;
  --r-lg: 20px;
  --r-pill: 100px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body { min-height: 100vh; }

/* Grain global */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 999;
  opacity: 0.035;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='200' height='200'><filter id='n'><feTurbulence baseFrequency='0.9' numOctaves='3' seed='5'/></filter><rect width='100%' height='100%' filter='url(%23n)' opacity='1'/></svg>");
  mix-blend-mode: overlay;
}

a { color: var(--accent); text-decoration: none; transition: color 0.15s; }
a:hover { color: var(--ink); }

/* ---------- No-JS fallback ---------- */
.noscript-msg {
  padding: 24px 28px;
  margin: 20px 40px;
  background: var(--bg-card);
  border: 1px solid var(--accent);
  border-left: 4px solid var(--accent);
  border-radius: var(--r-md);
  color: var(--ink);
  font-size: 15px;
  line-height: 1.6;
  max-width: 800px;
}
.noscript-msg strong { color: var(--accent); }
.noscript-msg a { color: var(--accent); border-bottom: 1px dotted var(--accent); padding-bottom: 1px; }

/* ---------- Top bar ---------- */
.topbar {
  display: flex;
  align-items: center;
  gap: var(--gap-lg);
  padding: 18px 40px;
  border-bottom: 1px solid var(--line);
  background: var(--bg-alt);
  position: sticky;
  top: 0;
  z-index: 100;
}
.topbar-brand {
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 400;
  letter-spacing: -0.01em;
  color: var(--ink);
}
.topbar-brand em { color: var(--accent); font-style: italic; }
.topbar-nav { display: flex; gap: var(--gap-md); margin-left: auto; }
.topbar-nav a {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--ink-dim);
  padding: 6px 10px;
  border-radius: var(--r-sm);
  transition: all 0.15s;
}
.topbar-nav a:hover, .topbar-nav a.active {
  color: var(--accent);
  background: rgba(240, 183, 66, 0.07);
}

/* ---------- Hero ---------- */
.hero {
  padding: 80px 40px 60px;
  border-bottom: 1px solid var(--line);
  position: relative;
  overflow: hidden;
  background: radial-gradient(circle at 85% 30%, rgba(240,183,66,0.08), transparent 50%);
}
.hero-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 18px;
}
.hero h1 {
  font-family: var(--font-serif);
  font-weight: 300;
  font-size: clamp(36px, 6vw, 80px);
  line-height: 0.98;
  letter-spacing: -0.02em;
  max-width: 1100px;
}
.hero h1 em {
  font-style: italic;
  font-weight: 400;
  color: var(--accent);
}
.hero p.lead {
  margin-top: 24px;
  font-size: 17px;
  color: var(--ink-dim);
  max-width: 680px;
  line-height: 1.6;
}

/* ---------- Sections ---------- */
.section {
  padding: var(--gap-xl) 40px;
  max-width: 1400px;
  margin: 0 auto;
}
.section-title {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: clamp(24px, 3vw, 38px);
  letter-spacing: -0.01em;
  margin-bottom: var(--gap-md);
}
.section-title em { color: var(--accent); font-style: italic; }
.section-subtitle {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: var(--gap-sm);
}

/* ---------- Cards ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: var(--gap-md);
}
.card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  padding: 28px;
  transition: all 0.2s ease;
  display: block;
  position: relative;
  overflow: hidden;
}
.card:hover {
  border-color: var(--accent-soft);
  transform: translateY(-2px);
  background: #201d18;
}
.card::before {
  content: "";
  position: absolute;
  top: 0; left: 0;
  width: 100%;
  height: 3px;
  background: var(--card-accent, var(--accent));
  opacity: 0.7;
}
.card-eyebrow {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--card-accent, var(--accent));
  margin-bottom: 10px;
}
.card-title {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: 26px;
  line-height: 1.1;
  letter-spacing: -0.01em;
  margin-bottom: 8px;
  color: var(--ink);
}
.card-subtitle {
  font-size: 14px;
  color: var(--ink-dim);
  line-height: 1.5;
  margin-bottom: 18px;
}
.card-meta {
  display: flex;
  gap: 14px;
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-faint);
}
.card-meta span { display: flex; align-items: center; gap: 6px; }

/* ---------- Tags ---------- */
.tag {
  display: inline-block;
  padding: 4px 10px;
  border-radius: var(--r-pill);
  border: 1px solid var(--line);
  background: transparent;
  color: var(--ink-dim);
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}
.tag.active { background: var(--accent); color: var(--bg); border-color: var(--accent); }
.tag-row { display: flex; gap: 6px; flex-wrap: wrap; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 18px;
  border-radius: var(--r-pill);
  border: 1px solid var(--line);
  background: transparent;
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all 0.15s;
}
.btn:hover { border-color: var(--accent); color: var(--accent); }
.btn-primary {
  background: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
}
.btn-primary:hover {
  background: transparent;
  color: var(--accent);
}

/* ---------- Forms ---------- */
.input {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  padding: 10px 14px;
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 14px;
  outline: none;
  width: 100%;
}
.input:focus { border-color: var(--accent); }

/* ---------- Footer ---------- */
.footer {
  padding: 40px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--ink-faint);
  text-transform: uppercase;
  text-align: center;
}
.footer a {
  color: var(--ink-dim);
  text-decoration: none;
  border-bottom: 1px dotted var(--line);
  padding-bottom: 1px;
  transition: color 0.15s, border-color 0.15s;
}
.footer a:hover { color: var(--accent); border-bottom-color: var(--accent-soft); }
.footer a[aria-current="page"] { color: var(--accent); border-bottom-color: var(--accent); }

/* ---------- Article reading ---------- */
.article-body {
  max-width: 720px;
  margin: 0 auto;
  font-size: 17px;
  line-height: 1.75;
  color: var(--ink);
}
.article-body h1 {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: clamp(34px, 4vw, 52px);
  line-height: 1.05;
  letter-spacing: -0.015em;
  margin: 0 0 14px;
}
.article-body h2 {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: 28px;
  letter-spacing: -0.01em;
  margin: 50px 0 14px;
  color: var(--accent);
}
.article-body h3 {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: 21px;
  margin: 36px 0 10px;
}
.article-body p { margin-bottom: 18px; }
.article-body em { font-style: italic; }
.article-body strong { color: var(--accent); font-weight: 600; }
.article-body ul, .article-body ol { margin: 12px 0 22px 28px; }
.article-body li { margin-bottom: 6px; }
.article-body blockquote {
  border-left: 3px solid var(--accent);
  padding: 4px 0 4px 18px;
  margin: 22px 0;
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 19px;
  color: var(--ink-dim);
}
.article-body code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background: var(--bg-card);
  padding: 2px 6px;
  border-radius: var(--r-xs);
  border: 1px solid var(--line);
}

/* ---------- Article metadata sidebar ---------- */
.article-frame {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 60px;
  max-width: 1100px;
  margin: 0 auto;
  padding: 60px 40px;
}
@media (max-width: 900px) {
  .article-frame { grid-template-columns: 1fr; gap: 40px; }
}
.article-meta {
  position: sticky;
  top: 100px;
  align-self: start;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-dim);
}
.article-meta dt {
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-bottom: 4px;
}
.article-meta dd {
  margin-bottom: 18px;
  color: var(--ink);
}
.article-meta a { display: block; padding: 4px 0; }

/* Headline d'article */
.article-head {
  max-width: 720px;
  margin: 0 auto 40px;
}
.article-eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cat-color, var(--accent));
  margin-bottom: 14px;
}
.article-summary {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 21px;
  line-height: 1.5;
  color: var(--ink-dim);
  margin: 18px 0 24px;
  padding-left: 14px;
  border-left: 2px solid var(--line);
}

/* ---------- Accessibilité WCAG AA ---------- */

/* Skip link : caché visuellement, révélé au focus clavier */
.skip-link {
  position: absolute;
  top: -100px;
  left: 12px;
  z-index: 10000;
  padding: 12px 18px;
  background: var(--accent);
  color: var(--bg);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-decoration: none;
  border-radius: var(--r-sm);
  transition: top 0.15s ease;
}
.skip-link:focus,
.skip-link:focus-visible {
  top: 12px;
  outline: 3px solid var(--ink);
  outline-offset: 2px;
}

/* Mode toggle (jeux : apprentissage vs défi) — partagé entre tous les jeux */
.mode-pill-group {
  display: inline-flex;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  overflow: hidden;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
}
.mode-pill {
  background: transparent;
  border: none;
  padding: 6px 14px;
  color: var(--ink-dim);
  cursor: pointer;
  transition: all 0.15s;
  font-family: inherit;
  font-size: inherit;
  letter-spacing: inherit;
}
.mode-pill:hover { color: var(--ink); }
.mode-pill.current {
  background: var(--accent);
  color: var(--bg);
}
.game-mode-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 18px;
  flex-wrap: wrap;
}
.game-mode-bar-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-faint);
}
.learn-banner {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 4px 12px;
  border-radius: var(--r-pill);
  background: rgba(143,168,71,0.12);
  color: var(--c-l3, var(--accent-soft));
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

/* Focus visible : anneau d'indication clair sur tous les éléments focusables */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: var(--r-xs);
}
button:focus-visible,
a:focus-visible,
input:focus-visible,
[tabindex]:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

/* Réduction des mouvements pour utilisateurs sensibles */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  /* Pas de confetti, pas de slide, pas de bounce */
  .confetti,
  .reward-headline,
  .reward-sub {
    animation: none !important;
    opacity: 1 !important;
    transform: none !important;
  }
}

/* Lecteurs d'écran : classe sr-only pour texte invisible mais annoncé */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- Glossary tooltip (mots techniques) ---------- */
.glossary {
  border-bottom: 1px dotted var(--accent);
  cursor: help;
  position: relative;
  text-decoration: none;
  color: inherit;
}
.glossary:hover { color: var(--accent); }
.glossary::after {
  content: attr(data-def);
  position: absolute;
  bottom: calc(100% + 10px);
  left: 50%;
  transform: translateX(-50%) translateY(4px);
  background: var(--bg-alt);
  border: 1px solid var(--accent-soft);
  padding: 12px 16px;
  border-radius: var(--r-md);
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 400;
  font-style: normal;
  color: var(--ink-dim);
  white-space: normal;
  width: max-content;
  max-width: 280px;
  text-align: left;
  letter-spacing: 0;
  text-transform: none;
  line-height: 1.45;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.18s ease, transform 0.18s ease;
  z-index: 200;
  box-shadow: 0 8px 24px rgba(0,0,0,0.4);
}
.glossary::before {
  content: "";
  position: absolute;
  bottom: calc(100% + 4px);
  left: 50%;
  transform: translateX(-50%);
  border: 6px solid transparent;
  border-top-color: var(--accent-soft);
  opacity: 0;
  transition: opacity 0.18s ease;
  z-index: 200;
  pointer-events: none;
}
.glossary:hover::after,
.glossary:focus::after {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}
.glossary:hover::before,
.glossary:focus::before { opacity: 1; }

/* ---------- Reading-level switcher (3 modes) ---------- */
.level-switch {
  display: inline-flex;
  border: 1px solid var(--line);
  border-radius: var(--r-pill);
  padding: 3px;
  background: var(--bg-card);
}
.level-switch button {
  padding: 7px 14px;
  border: none;
  background: transparent;
  color: var(--ink-dim);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  cursor: pointer;
  border-radius: var(--r-pill);
  transition: all 0.15s;
}
.level-switch button:hover { color: var(--ink); }
.level-switch button.on {
  background: var(--accent);
  color: var(--bg);
}
.level-switch-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin-right: 12px;
}

/* ---------- Utilities ---------- */
.muted { color: var(--ink-dim); }
.faint { color: var(--ink-faint); }
.mono  { font-family: var(--font-mono); }
.serif { font-family: var(--font-serif); }
.center { text-align: center; }
.flex { display: flex; }
.flex-col { display: flex; flex-direction: column; }
.gap-sm { gap: var(--gap-sm); }
.gap-md { gap: var(--gap-md); }
.mt-sm { margin-top: var(--gap-sm); }
.mt-md { margin-top: var(--gap-md); }
.mt-lg { margin-top: var(--gap-lg); }

/* ---------- Topbar mobile : bouton hamburger ---------- */
.topbar-nav-toggle-input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
  margin: -1px;
}
.topbar-nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: var(--r-sm);
  width: 40px;
  height: 40px;
  cursor: pointer;
  margin-left: auto;
  padding: 0;
  position: relative;
  transition: border-color 0.15s;
}
.topbar-nav-toggle:hover { border-color: var(--accent-soft); }
.topbar-nav-toggle-input:focus-visible + .topbar-nav-toggle {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-color: var(--accent);
}
.topbar-nav-toggle span {
  display: block;
  position: absolute;
  left: 50%;
  width: 18px;
  height: 1.5px;
  background: var(--ink);
  transform: translateX(-50%);
  transition: all 0.2s ease;
}
.topbar-nav-toggle span:nth-child(1) { top: 13px; }
.topbar-nav-toggle span:nth-child(2) { top: 19px; }
.topbar-nav-toggle span:nth-child(3) { top: 25px; }
.topbar-nav-toggle[aria-expanded="true"] span:nth-child(1) {
  top: 19px; transform: translateX(-50%) rotate(45deg);
}
.topbar-nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.topbar-nav-toggle[aria-expanded="true"] span:nth-child(3) {
  top: 19px; transform: translateX(-50%) rotate(-45deg);
}

/* ---------- Responsive ---------- */
@media (max-width: 768px) {
  .topbar {
    padding: 12px 20px;
    gap: var(--gap-sm);
    flex-wrap: wrap;
  }
  .topbar-brand { font-size: 16px; }

  .topbar-nav-toggle { display: block; }

  .topbar-nav {
    display: none;
    flex-direction: column;
    gap: 0;
    margin-left: 0;
    width: 100%;
    padding-top: 12px;
    border-top: 1px solid var(--line);
    margin-top: 4px;
  }
  .topbar-nav.is-open { display: flex; }
  /* No-JS fallback : checkbox sibling toggle (HTML statique) */
  .topbar-nav-toggle-input:checked ~ .topbar-nav { display: flex; }
  .topbar-nav-toggle-input:checked ~ .topbar-nav-toggle span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
  .topbar-nav-toggle-input:checked ~ .topbar-nav-toggle span:nth-child(2) { opacity: 0; }
  .topbar-nav-toggle-input:checked ~ .topbar-nav-toggle span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }
  .topbar-nav a {
    padding: 12px 14px;
    border-radius: var(--r-sm);
    border-left: 2px solid transparent;
    font-size: 12px;
  }
  .topbar-nav a:hover, .topbar-nav a.active, .topbar-nav a[aria-current="page"] {
    border-left-color: var(--accent);
    background: rgba(240, 183, 66, 0.05);
  }

  .hero { padding: 50px 20px 40px; }
  .hero h1 { font-size: clamp(28px, 7vw, 48px); }
  .section { padding: 40px 20px; }
  .article-frame { padding: 40px 20px; }

  /* Tableaux markdown : scroll horizontal pour ne pas casser la mise en page */
  .article-content table,
  table {
    display: block;
    overflow-x: auto;
    max-width: 100%;
    -webkit-overflow-scrolling: touch;
  }

  /* Footer : padding réduit */
  .footer { padding: 30px 20px; font-size: 11px; }

  /* Touch targets ≥ 44×44 px (Apple HIG / WCAG 2.5.5) — appliqué sur les écrans tactiles */
  .btn,
  button:not(.topbar-nav-toggle),
  .topbar-nav a,
  .scenario-pill, .mode-btn, .ctrl-btn, .speed-btn,
  .year-pill, .filter-btn,
  .object-modal-close {
    min-height: 44px;
    box-sizing: border-box;
  }
  .topbar-nav-toggle {
    width: 44px;
    height: 44px;
  }
  .object-modal-close { min-width: 44px; }
}

/* Très petits écrans (< 480px) : ajustements supplémentaires */
@media (max-width: 480px) {
  .hero h1 { font-size: clamp(24px, 8vw, 36px); }
  .hero .lead { font-size: 14px; }
  .topbar-brand { font-size: 14px; }
  .home-stat-n { font-size: 30px; }
}