:root{
  --bg: #ffffff;
  --surface: #f7f7f7;
  --card: #ffffff;
  --text: #111111;
  --muted: #5b5b5b;
  --border: #e8e8e8;
  --shadow: 0 8px 22px rgba(0,0,0,.06);
  --radius: 16px;
  --radius-sm: 12px;
  --max: 1080px;
  --pad: 20px;
  --accent: #007FFF;
}

*{ box-sizing: border-box; }

html, body{
  margin:0;
  padding:0;
}

html{
  scroll-behavior: smooth;
}

body{
  font-family: Arial, Helvetica, sans-serif;
  line-height: 1.5;
  color: var(--text);
  background: var(--bg);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container{
  width: min(100%, var(--max));
  margin: 0 auto;
  padding: 0 var(--pad);
}

.skip-link{
  position:absolute;
  left:-999px;
  top:auto;
  width:1px;
  height:1px;
  overflow:hidden;
}
.skip-link:focus{
  left: 12px;
  top: 12px;
  width:auto;
  height:auto;
  padding: 10px 12px;
  border-radius: 10px;
  background: #000;
  color:#fff;
  z-index: 9999;
}

/* Header */
.site-header{
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.header-inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 16px;
  padding: 14px 0;
}
.brand{
  display:flex;
  align-items:center;
  gap: 12px;
  text-decoration:none;
  color: var(--text);
}
.brand-mark{
  width: 36px;
  height: 36px;
  border-radius: 12px;
  display:flex;
  align-items:center;
  justify-content:center;
  background: var(--accent); /* accent Azure */
  color: #fff;
  font-weight: 700;
}
.brand-title{
  display:block;
  font-size: 16px;
  font-weight: 700;
}
.brand-subtitle{
  display:block;
  font-size: 13px;
  color: var(--muted);
}

.nav{
  display:flex;
  gap: 14px;
  align-items:center;
  flex-wrap: wrap;
}
.nav a{
  text-decoration:none;
  color: var(--text);
  font-size: 14px;
}
.nav a:hover{
  text-decoration: underline;
  color: var(--accent);
}
.nav-pill{
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: #fff;
  box-shadow: 0 1px 0 rgba(0,0,0,.03);
}
.nav-pill:hover{ text-decoration:none; }

/* Hero */
.hero{
  padding: 52px 0 28px;
  background: linear-gradient(to bottom, #ffffff, #fafafa);
}
.hero-grid{
  display:grid;
  grid-template-columns: 1.2fr .8fr;
  gap: 22px;
  align-items:start;
}
.kicker{
  margin:0 0 8px;
  color: var(--muted);
  font-size: 14px;
}
h1{
  margin:0 0 12px;
  font-size: clamp(28px, 3.3vw, 42px);
  line-height: 1.15;
}
.muted{ color: var(--muted); }
.lead{
  margin: 0 0 18px;
  color: #222;
  font-size: 16px;
}
.meta{
  display:flex;
  gap: 14px;
  flex-wrap: wrap;
  margin-top: 14px;
  color: var(--muted);
  font-size: 13px;
}

.card{
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.card-body{ padding: 18px; }
.card-title{ margin: 0 0 6px; font-size: 16px; }
.card-text{ margin: 0 0 14px; color: var(--muted); }

.stack{ display:flex; flex-direction:column; gap: 10px; }
.sep{
  border: none;
  border-top: 1px solid var(--border);
  margin: 16px 0;
}
.small{ font-size: 13px; }
code{
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
  font-size: 12px;
}

/* Couverture du livre dans la carte d'accueil (centrage robuste) */
.book-cover{
  width: 100%;
  margin: 0 0 8px 0;
  text-align: center;
}

.section + .hero {
  margin-top: 40px;
}

.hero-card {
  margin-top: -20px;
}

.book-cover img{
	display: inline-block;
	margin: 0 !important;   /* neutralise toute marge héritée */
	padding: 0 !important;  /* neutralise tout padding */
	max-width: 160px;
	width: 100%;
	height: auto;
	border-radius: 6px;
	box-shadow: 0 4px 10px rgba(0,0,0,0.15);
	text-align: center;
}

/* Buttons */
.btn{
  display:inline-flex;
  justify-content:center;
  align-items:center;
  gap: 8px;
  padding: 10px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
  text-decoration:none;
  font-size: 14px;
}
.btn:hover{ box-shadow: 0 6px 18px rgba(0,0,0,.06); }
.btn.primary{
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.btn.subtle{
  background: #fafafa;
}

.note {
  padding: 16px;
  align-self: start;
}

/* Sections */
.section{ padding: 34px 0; }
section{ scroll-margin-top: 90px; }

.section h2{ margin: 0 0 10px; font-size: 22px; }
.two-col{
  display:grid;
  grid-template-columns: 1fr 1fr;
  gap: 22px;
}
.note{
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  background: #fafafa;
}
.note h3{ margin: 0 0 8px; font-size: 16px; }
.note ul{ margin: 0; padding-left: 18px; color: var(--muted); }

.grid-3{
  display:grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.tile{
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: 0 1px 0 rgba(0,0,0,.03);
}
.tile h3{ margin: 0 0 6px; }
.tile p{ margin: 0 0 12px; color: var(--muted); }

/* Audio */
.audio-card{
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #fff;
  padding: 16px;
  box-shadow: 0 1px 0 rgba(0,0,0,.03);
}
.audio-row{
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap: 12px;
  margin-bottom: 12px;
}
.audio-list{ /* <-- correction: .audio-list (classe) */
  display: grid;
  gap: 14px;
  margin-top: 16px;
}
.audio-item{
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #fff;
  padding: 16px;
  box-shadow: 0 1px 0 rgba(0,0,0,.03);
}
.audio-item-head{
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap: 12px;
  margin-bottom: 10px;
}
.audio-title{
  margin: 0 0 2px;
  font-size: 16px;
}
.audio{ width: 100%; }

/* Reader page */
.reader-page{ padding: 22px 0 36px; }
.reader-shell{
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow);
  overflow: hidden;
}
.reader-toolbar{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap: 12px;
  padding: 12px;
  border-bottom: 1px solid var(--border);
  background: #fcfcfc;
}
.toolbar-center{ display:flex; gap: 10px; align-items:center; }
.icon-btn{
  width: 44px;
  height: 36px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: #fff;
  cursor: pointer;
}
.icon-btn:hover{ box-shadow: 0 6px 18px rgba(0,0,0,.06); }

.viewer{
    height: min(92vh, 1180px);
  padding: 8px;
  background: #fff;
  overflow: auto;
}

.reader-hint{
  padding: 12px 14px;
  border-top: 1px solid var(--border);
  background: #fcfcfc;
}

/* TOC */
.toc{
  max-height: 260px;
  overflow:auto;
  border-bottom: 1px solid var(--border);
  padding: 10px 12px;
  background: #fff;
}
.toc a{
  display:block;
  padding: 8px 10px;
  border-radius: 10px;
  text-decoration:none;
  color: var(--text);
  border: 1px solid transparent;
}
.toc a:hover{
  background: #fafafa;
  border-color: var(--accent);
}
.hidden{ display:none; }

/* Footer */
.site-footer{
  border-top: 1px solid var(--border);
  padding: 26px 0;
  background: #fafafa; /* <-- correction: un seul # */
}
.footer-inner{
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap: 12px;
  flex-wrap: wrap;
  padding-top: 6px;
}
.site-footer a{ color: var(--muted); text-decoration:none; }
.site-footer a:hover{ text-decoration: underline; }

/* Diagram language separator */
.diagram-separator{
  position: relative;
  max-width: 1000px;
  margin: 90px auto;
  text-align: center;
}

.diagram-separator::before{
  content:"";
  position:absolute;
  top:50%;
  left:0;
  width:100%;
  height:1px;
  background: var(--border);
  z-index:1;
}

.diagram-separator span{
  position: relative;
  z-index:2;
  display:inline-block;
  padding: 0 20px;
  background: var(--bg);
  font-size:13px;
  letter-spacing:2px;
  text-transform:uppercase;
  color: var(--muted);
}

/* Responsive */
@media (max-width: 900px){
  .hero-grid{ grid-template-columns: 1fr; }
  .two-col{ grid-template-columns: 1fr; }
  .grid-3{ grid-template-columns: 1fr; }
  .nav{ gap: 10px; }
}