:root {
    --or: #ffc857;
    --rouge: #c4452d;
    --cuivre: #8f3f22;
    --fonce: #140b08;
    --clair: #fff4e0;
    --bleu: #68b7d9;
  }
  * { margin: 0; padding: 0; box-sizing: border-box; }
  html { scroll-behavior: smooth; }
  body {
    font-family: 'Segoe UI', Arial, sans-serif;
    background: radial-gradient(circle at 20% 0%, #412014 0%, var(--fonce) 48%, #050303 100%);
    color: var(--clair);
    line-height: 1.7;
  }
  header {
    background:
      radial-gradient(circle at 50% 35%, rgba(255,200,87,.9), rgba(196,69,45,.75) 35%, rgba(58,20,14,.9) 68%, rgba(0,0,0,.95) 100%),
      linear-gradient(135deg, #7b2f1e, #1b0906);
    text-align: center;
    padding: 100px 20px;
    color: #fff;
    box-shadow: inset 0 -40px 70px rgba(0,0,0,.6);
  }
  header h1 { font-size: clamp(2.1rem, 6vw, 3.4rem); margin-bottom: 15px; text-shadow: 0 3px 10px rgba(0,0,0,.45); }
  header p { font-size: 1.25rem; max-width: 760px; margin: 0 auto; }
  .cta {
    display: inline-block;
    margin-top: 30px;
    padding: 15px 36px;
    background: #fff;
    color: var(--rouge);
    font-weight: bold;
    text-decoration: none;
    border-radius: 40px;
    transition: transform .2s, box-shadow .2s;
  }
  .cta:hover { transform: scale(1.06); box-shadow: 0 12px 30px rgba(0,0,0,.28); }
  section { max-width: 980px; margin: 0 auto; padding: 60px 25px; }
  h2 { color: var(--or); font-size: 2rem; margin-bottom: 25px; border-bottom: 2px solid var(--rouge); padding-bottom: 10px; }
  h3 { color: var(--or); margin: 25px 0 10px; }
  ul { margin-left: 22px; line-height: 1.9; }
  #why > p { margin-bottom: 34px; }
  #why .grille { margin-top: 8px; }
  .grille { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 20px; margin: 24px 0; }
  .carte {
    background: rgba(255,200,87,.08);
    border: 1px solid rgba(255,200,87,.28);
    border-radius: 12px;
    padding: 25px;
    transition: transform .2s, background .2s;
  }
  .carte:hover { transform: translateY(-5px); background: rgba(255,200,87,.15); }
  .carte .num { font-size: 2.45rem; color: var(--rouge); font-weight: bold; line-height: 1.1; }
  code {
    display: block;
    background: #000;
    color: #7CFC00;
    padding: 12px;
    border-radius: 8px;
    margin: 10px 0;
    font-family: Consolas, monospace;
    overflow-x: auto;
    white-space: pre-wrap;
  }
  table { width: 100%; border-collapse: collapse; margin: 20px 0; }
  th, td { padding: 12px; border: 1px solid rgba(255,200,87,.3); text-align: left; vertical-align: top; }
  th { background: rgba(196,69,45,.42); color: var(--or); }
  .step { border-left: 4px solid var(--or); padding-left: 20px; margin: 20px 0; }
  footer { text-align: center; padding: 40px; background: #000; color: #aaa; }
  .avert { background: rgba(196,69,45,.16); border-left: 4px solid var(--rouge); padding: 15px 20px; border-radius: 6px; margin: 20px 0; }
  .formule {
    display: block;
    background: #000;
    color: #ffd27a;
    padding: 14px 18px;
    border-radius: 8px;
    margin: 12px 0;
    font-family: 'Cambria Math', Cambria, 'Segoe UI', serif;
    font-style: italic;
    overflow-x: auto;
    border-left: 3px solid var(--or);
  }
  .lang-switch {
    position: fixed; top: 15px; right: 15px; z-index: 1000;
    display: flex; gap: 4px;
    background: rgba(20,11,8,.86);
    border: 1px solid rgba(255,200,87,.42);
    border-radius: 30px; padding: 4px;
    backdrop-filter: blur(4px);
  }
  .lang-switch button {
    border: none; background: transparent; color: var(--clair);
    font-weight: bold; font-family: inherit;
    padding: 6px 14px; border-radius: 20px; cursor: pointer;
  }
  .lang-switch button.actif { background: var(--or); color: var(--fonce); }
  .social-share {
    position: fixed; top: 15px; left: 15px; z-index: 1000;
    display: inline-flex; align-items: center; justify-content: center;
    width: 42px; height: 42px;
    border-radius: 50%;
    background: #1877f2;
    color: #fff;
    border: 1px solid rgba(255,255,255,.28);
    box-shadow: 0 8px 24px rgba(0,0,0,.24);
    transition: transform .2s, box-shadow .2s;
  }
  .social-share:hover { transform: scale(1.08); box-shadow: 0 12px 30px rgba(0,0,0,.32); }
  .social-share svg { width: 24px; height: 24px; display: block; fill: currentColor; }
  .sim-controls { display: flex; align-items: center; gap: 15px; flex-wrap: wrap; margin: 20px 0; }
  .sim-controls input[type=range] { flex: 1; min-width: 200px; accent-color: var(--or); }
  #simCanvas {
    width: 100%; height: auto; background: #050505;
    border: 1px solid rgba(255,200,87,.35); border-radius: 10px;
  }
  @media (max-width: 620px) {
    section { padding: 45px 18px; }
    table { font-size: .92rem; }
    th, td { padding: 9px; }
    .lang-switch { top: 10px; right: 10px; }
    .social-share { top: 10px; left: 10px; }
  }