/* Noyau — page de présentation. HTML, CSS et JS sans dépendance. */
:root{
  --paper:#F6F2EA; --paper-2:#EDE6D8; --card:#FFFFFF;
  --ink:#13201E; --ink-2:#2C3C39; --muted:#5B6A66;
  --teal:#0F5B57; --teal-d:#0A3F3D; --amber:#E2A13B; --amber-d:#8A5A10;
  --line:rgba(19,32,30,.14); --ok:#2F7D5B; --warn:#B4452E;
  --night:#0D1A19; --night-2:#142827; --night-line:rgba(234,228,214,.16); --sand:#EAE4D6; --night-muted:#A9B8B3;
  --serif:"Iowan Old Style","Palatino Linotype",Palatino,"Book Antiqua",Georgia,serif;
  --sans:-apple-system,BlinkMacSystemFont,"Segoe UI",system-ui,Roboto,"Helvetica Neue",sans-serif;
  --radius:20px; --shadow:0 30px 60px -34px rgba(19,32,30,.45);
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{margin:0;background:var(--paper);color:var(--ink);font:17px/1.6 var(--sans);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
a{color:inherit}
h1,h2,h3{font-family:var(--serif);font-weight:600;letter-spacing:-.015em;margin:0}
p{margin:0 0 1em}
ul,ol{margin:0}
[hidden]{display:none!important}
.wrap{width:min(1120px,100% - 48px);margin-inline:auto}
.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}
.skip{position:absolute;left:12px;top:-64px;background:var(--ink);color:#fff;padding:10px 14px;border-radius:10px;z-index:100}
.skip:focus{top:12px}
:focus-visible{outline:3px solid var(--amber);outline-offset:3px}

/* Navigation */
.nav{position:sticky;top:0;z-index:50;background:rgba(246,242,234,.84);backdrop-filter:saturate(1.4) blur(14px);-webkit-backdrop-filter:saturate(1.4) blur(14px);border-bottom:1px solid transparent;transition:border-color .2s}
.nav.is-scrolled{border-bottom-color:var(--line)}
.nav-inner{display:flex;align-items:center;justify-content:space-between;height:64px}
.brand{display:inline-flex;align-items:center;gap:10px;text-decoration:none;font-family:var(--serif);font-weight:600;font-size:23px;color:var(--teal-d);flex:none}
.brand-mark{width:28px;height:28px;color:var(--teal)}
.nav-links{display:flex;gap:26px;font-size:15px}
.nav-links a{text-decoration:none;color:var(--ink-2);padding:6px 0}
.nav-links a:hover{color:var(--teal)}

/* Boutons */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:14px 24px;border-radius:999px;font:600 16px/1 var(--sans);text-decoration:none;border:1px solid transparent;cursor:pointer;transition:background .2s,border-color .2s,transform .15s}
.btn:active{transform:translateY(1px)}
.btn-primary{background:var(--teal);color:#fff}
.btn-primary:hover{background:var(--teal-d)}
.btn-ghost{border-color:var(--line);background:rgba(255,255,255,.55);color:var(--ink)}
.btn-ghost:hover{border-color:var(--teal)}
.btn-small{padding:10px 18px;font-size:14px;background:var(--paper-2);color:var(--ink);border-color:var(--line)}
.btn-small:hover{border-color:var(--teal)}

/* Hero */
.hero{position:relative;overflow:hidden;padding:48px 0 80px}
.hero::before,.hero::after{content:"";position:absolute;border-radius:50%;border:1px solid var(--line);pointer-events:none}
.hero::before{right:-220px;top:-160px;width:700px;height:700px}
.hero::after{right:-360px;top:-300px;width:980px;height:980px;border-color:rgba(19,32,30,.07)}
.hero-grid{position:relative;display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,.95fr);gap:56px;align-items:center}
.eyebrow{display:inline-flex;align-items:center;gap:10px;margin:0 0 24px;padding:7px 14px;border:1px solid var(--line);border-radius:999px;background:rgba(255,255,255,.6);font-size:14px;color:var(--ink-2)}
.eyebrow .dot{width:8px;height:8px;border-radius:50%;background:var(--amber)}
h1{font-size:clamp(38px,5.2vw,64px);line-height:1.04;letter-spacing:-.025em;text-wrap:balance}
.lead{font-size:clamp(18px,1.6vw,21px);color:var(--ink-2);max-width:52ch;margin:24px 0 32px}
.cta-row{display:flex;flex-wrap:wrap;gap:12px}
.chips{display:flex;flex-wrap:wrap;gap:10px;list-style:none;padding:0;margin:36px 0 0}
.chips li{padding:8px 14px;border-radius:999px;background:var(--paper-2);font-size:14px;color:var(--ink-2)}

/* Démonstration */
.demo-card{display:grid;gap:16px;justify-items:center;scroll-margin-top:90px}
.demo-head{text-align:center;max-width:420px}
.demo-head h2{font:700 13px/1 var(--sans);letter-spacing:.14em;text-transform:uppercase;color:var(--teal);margin:0 0 10px;max-width:none}
.demo-head p{font-size:14.5px;color:var(--muted);margin:0}
.device{width:min(100%,456px);background:var(--card);border:1px solid var(--line);border-radius:30px;padding:14px 14px 16px;box-shadow:var(--shadow)}
.device-top{display:flex;align-items:center;gap:10px;margin-bottom:12px}
.device-dots{display:flex;gap:5px}
.device-dots i{width:8px;height:8px;border-radius:50%;background:var(--paper-2);display:block}
.url-pill{flex:1;min-width:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;font-size:12.5px;color:var(--muted);background:var(--paper);border-radius:999px;padding:6px 12px;text-align:center}
.feed{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px}
.tile{position:relative;aspect-ratio:1/1;border-radius:14px;overflow:hidden;background:#D9D1C0}
.tile-art{position:absolute;inset:0}
.tile-art svg{display:block;width:100%;height:100%}
.tile-veil{position:absolute;inset:0;z-index:1;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;padding:10px 10px 38px;text-align:center;color:var(--ink-2);background:repeating-linear-gradient(135deg,rgba(19,32,30,.07) 0 9px,rgba(19,32,30,0) 9px 18px),linear-gradient(160deg,#D8D0BE,#C6BDA7);transition:opacity .5s ease;overflow:hidden}
.tile-veil .lock{width:24px;height:24px;opacity:.75}
.tile-status{font-size:13px;font-weight:700}
.tile-reason{font-size:11.5px;line-height:1.3;color:var(--muted);min-height:1.3em}
.tile[data-state="revealed"] .tile-veil{opacity:0;pointer-events:none}
.tile[data-state="analysing"] .tile-veil::before{content:"";position:absolute;inset:0;background:linear-gradient(100deg,transparent 30%,rgba(255,255,255,.6) 50%,transparent 70%);transform:translateX(-100%);animation:sweep 1.1s ease-in-out infinite}
@keyframes sweep{to{transform:translateX(100%)}}
.tile-badge{position:absolute;left:8px;bottom:8px;z-index:2;display:inline-flex;align-items:center;gap:6px;padding:3px 10px 3px 8px;border-radius:999px;background:rgba(255,255,255,.94);font-size:12px;font-weight:700;color:var(--ink)}
.tile-badge i{width:8px;height:8px;border-radius:50%;background:var(--ok);display:block}
.tile-badge[data-kind="warn"] i{background:var(--warn)}
.noscript{font-size:14px;color:var(--muted);margin:12px 0 0}
.demo-controls{display:grid;justify-items:center;gap:14px}
.control-row{display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:12px 20px}
.field{display:flex;align-items:center;gap:10px}
.field-label{font-size:14px;color:var(--muted)}
.demo-status{min-height:2.9em;max-width:456px;text-align:center;font-size:14.5px;color:var(--ink-2);margin:0}
.demo-hint{max-width:456px;text-align:center;font-size:13.5px;color:var(--muted);margin:0}

/* Contrôles */
.segmented{display:inline-flex;padding:4px;border-radius:999px;background:var(--paper-2);border:1px solid var(--line)}
.segmented button{appearance:none;border:0;background:transparent;font:600 14px/1 var(--sans);color:var(--ink-2);padding:9px 16px;border-radius:999px;cursor:pointer;transition:background .2s,color .2s}
.segmented button[aria-checked="true"]{background:var(--teal);color:#fff}
.switch{position:relative;display:inline-flex;align-items:center;gap:10px;font-size:14px;cursor:pointer}
.switch input{position:absolute;opacity:0;width:1px;height:1px}
.switch-ui{width:40px;height:24px;border-radius:999px;background:#C9C0AB;position:relative;transition:background .2s;flex:none}
.switch-ui::after{content:"";position:absolute;top:3px;left:3px;width:18px;height:18px;border-radius:50%;background:#fff;transition:transform .2s}
.switch input:checked + .switch-ui{background:var(--warn)}
.switch input:checked + .switch-ui::after{transform:translateX(16px)}
.switch input:focus-visible + .switch-ui{outline:3px solid var(--amber);outline-offset:3px}

/* Sections */
.section{padding:104px 0}
.tinted{background:var(--paper-2)}
.kicker{font:700 13px/1 var(--sans);letter-spacing:.14em;text-transform:uppercase;color:var(--teal);margin:0 0 18px}
h2{font-size:clamp(30px,4.2vw,48px);line-height:1.08;max-width:30ch;text-wrap:balance}
.section-lead{max-width:62ch;font-size:19px;color:var(--ink-2);margin:22px 0 0}
.fine{margin:28px 0 0;font-size:15px;color:var(--muted);max-width:70ch}
.icon{width:30px;height:30px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round;color:var(--teal);margin-bottom:16px}
.icon-light{color:#fff;flex:none;margin:2px 0 0}

/* Comparaison */
.compare{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px;margin-top:40px}
.compare-card{border-radius:var(--radius);padding:32px;border:1px solid var(--line);background:var(--card)}
.compare-card h3{font-size:27px;margin-bottom:12px}
.compare-card p:last-child{margin-bottom:0}
.compare-closed{background:repeating-linear-gradient(135deg,rgba(19,32,30,.045) 0 10px,rgba(19,32,30,0) 10px 20px),var(--paper-2)}
.compare-open{background:var(--teal);color:#fff;border-color:transparent}
.compare-tag{font:700 12.5px/1 var(--sans);letter-spacing:.12em;text-transform:uppercase;margin:0 0 16px;color:var(--muted)}
.compare-open .compare-tag{color:#F2CF8E}
.compare-open p:not(.compare-tag){color:rgba(255,255,255,.9)}

/* Principe */
.night{background:var(--night);color:var(--sand)}
.night .kicker{color:var(--amber)}
.night h2{color:#F4EEDF}
.two-col{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:56px;align-items:start;margin-top:44px}
.prose p{color:#CFD8D3;font-size:18px}
.night .rule{margin-top:30px;padding-left:18px;border-left:3px solid var(--amber);font-family:var(--serif);font-size:26px;line-height:1.3;color:#F4EEDF}
.lock-card{background:var(--night-2);border:1px solid var(--night-line);border-radius:var(--radius);padding:30px}
.lock-card h3{font-size:23px;color:#F4EEDF;margin-bottom:18px}
.segmented-night{background:rgba(255,255,255,.06);border-color:var(--night-line)}
.segmented-night button{color:#CFD8D3}
.segmented-night button[aria-checked="true"]{background:var(--amber);color:#1A1405}
.steps{list-style:none;margin:26px 0 0;padding:0;counter-reset:step}
.steps li{position:relative;padding:0 0 22px 46px;counter-increment:step}
.steps li::before{content:counter(step);position:absolute;left:0;top:0;width:30px;height:30px;border-radius:50%;background:var(--night);border:1px solid var(--night-line);color:var(--amber);display:grid;place-items:center;font:700 13px/1 var(--sans)}
.steps li:not(:last-child)::after{content:"";position:absolute;left:15px;top:36px;bottom:6px;width:1px;background:var(--night-line)}
.steps strong{display:block;color:#F4EEDF;font-weight:600}
.steps em{font-style:normal}
.steps li > span{color:var(--night-muted);font-size:15px}
.night .lock-result{margin:6px 0 0;padding:14px 16px;border-radius:14px;background:rgba(226,161,59,.13);color:#F4EEDF;font-size:15.5px}

/* Couches */
.cards{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px;margin-top:40px}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:30px}
.card h3{font-size:25px;margin-bottom:10px}
.card p{color:var(--ink-2)}
.limit{margin:18px 0 0;padding:11px 14px;border-left:3px solid var(--amber);background:rgba(226,161,59,.11);font-size:14.5px;border-radius:0 12px 12px 0}
.card .limit{margin-bottom:0}

/* Niveaux */
.levels{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px;margin-top:40px}
.level{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:30px;display:flex;flex-direction:column}
.level-tag{font:700 12.5px/1 var(--sans);letter-spacing:.12em;text-transform:uppercase;color:var(--teal);margin:0 0 12px}
.level h3{font-size:28px;margin-bottom:6px}
.level ul{padding-left:20px;margin:6px 0 20px;color:var(--ink-2)}
.level li{margin-bottom:6px}
.still{margin:auto 0 0;font-size:14.5px;color:var(--muted)}
.still b{color:var(--ink-2)}
.callout{display:flex;gap:16px;align-items:flex-start;margin-top:24px;padding:24px 28px;border-radius:var(--radius);background:var(--teal);color:#fff}
.callout p{margin:0;color:rgba(255,255,255,.92)}

/* Limites */
.limits{list-style:none;padding:0;margin:40px 0 0;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}
.limits li{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:28px}
.limits h3{font-size:23px;margin-bottom:8px}
.limits p{margin:0;color:var(--ink-2)}

/* Avancement */
.road{list-style:none;padding:0;margin:40px 0 0;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:20px}
.road li{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:24px}
.road h3{font-size:22px;margin-bottom:8px}
.road p:last-child{margin-bottom:0;font-size:15px;color:var(--ink-2)}
.road-state{display:inline-flex;align-items:center;gap:8px;font:700 12.5px/1 var(--sans);letter-spacing:.1em;text-transform:uppercase;margin:0 0 14px}
.road-state i{width:9px;height:9px;border-radius:50%;background:currentColor;display:block}
.road-done .road-state{color:var(--ok)}
.road-next .road-state{color:var(--amber-d)}

/* Pied de page */
footer{padding:44px 0 64px;border-top:1px solid var(--line);color:var(--muted);font-size:14.5px}
footer p{margin:0 0 6px}
.brand-line b{color:var(--ink)}

/* Écrans moyens et petits */
@media (max-width:980px){
  .hero-grid{grid-template-columns:1fr;gap:48px}
  .two-col{grid-template-columns:1fr;gap:36px}
  .levels{grid-template-columns:1fr}
  .road{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:720px){
  body{font-size:16.5px}
  .wrap{width:min(1120px,100% - 36px)}
  .section{padding:72px 0}
  .hero{padding:40px 0 64px}
  .hero::before,.hero::after{display:none}
  .feed{grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}
  .cards,.compare,.limits,.road{grid-template-columns:1fr}
  .nav-links{gap:18px;overflow-x:auto;scrollbar-width:none;margin-left:16px}
  .nav-links::-webkit-scrollbar{display:none}
  .nav-links a{white-space:nowrap}
  .compare-card,.card,.level,.limits li,.lock-card{padding:24px}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.001ms!important;animation-iteration-count:1!important;transition-duration:.001ms!important}
}