/* ============================================================
   IA & pièces écrites — BTS MEC · vue linéaire et accueil
   ============================================================ */

:root {
  --encre: #1c2b39;
  --encre-doux: #51606e;
  --papier: #f7f6f2;
  --blanc: #ffffff;
  --accent: #0e5a8a;      /* bleu profond */
  --accent-clair: #e8f0f6;
  --ocre: #b06f1f;        /* accent chantier */
  --ocre-clair: #faf3e6;
  --ligne: #e2ded4;
  --serif: Georgia, "Times New Roman", serif;
  --sans: "Segoe UI", system-ui, -apple-system, Roboto, sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 4.5rem; }

body {
  margin: 0;
  background: var(--papier);
  color: var(--encre);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.65;
}

/* ---------- bandeau ---------- */

.bandeau {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--encre);
  color: #fff;
  box-shadow: 0 1px 6px rgba(28, 43, 57, .25);
}

.bandeau-in {
  max-width: 78rem;
  margin: 0 auto;
  padding: .65rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.marque {
  font-family: var(--serif);
  font-size: 1.15rem;
  color: #fff;
  text-decoration: none;
  letter-spacing: .01em;
  white-space: nowrap;
}
.marque span { color: var(--ocre); }

.marque-sous {
  font-size: .85rem;
  color: #b9c4cf;
}

.bandeau-nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: .25rem;
  flex-wrap: wrap;
}

.bandeau-nav a {
  color: #d6dee6;
  text-decoration: none;
  font-size: .9rem;
  padding: .3rem .7rem;
  border-radius: 4px;
}
.bandeau-nav a:hover { background: rgba(255, 255, 255, .12); color: #fff; }
.bandeau-nav a.actif { background: rgba(255, 255, 255, .16); color: #fff; font-weight: 600; }

.bandeau-nav .btn-diapos {
  margin-left: .6rem;
  background: var(--ocre);
  color: #fff;
  font-weight: 600;
}
.bandeau-nav .btn-diapos:hover { background: #c8821f; }

/* ---------- gabarit deux colonnes ---------- */

.page-lineaire {
  max-width: 78rem;
  margin: 0 auto;
  padding: 2.2rem 1.25rem 4rem;
  display: grid;
  grid-template-columns: minmax(0, 47rem) 15.5rem;
  gap: 3rem;
  justify-content: center;
}

/* ---------- article ---------- */

.article { min-width: 0; }

.surtitre {
  font-size: .82rem;
  font-weight: 600;
  letter-spacing: .09em;
  text-transform: uppercase;
  color: var(--ocre);
  margin: 0 0 .4rem;
}

.article h1 {
  font-family: var(--serif);
  font-size: 2.05rem;
  line-height: 1.25;
  margin: 0 0 1.2rem;
  color: var(--encre);
}

.article h2 {
  font-family: var(--serif);
  font-size: 1.5rem;
  margin: 2.6rem 0 .8rem;
  padding-bottom: .35rem;
  border-bottom: 2px solid var(--ligne);
  color: var(--accent);
}

.article h3 {
  font-size: 1.13rem;
  margin: 1.9rem 0 .6rem;
  color: var(--encre);
}

.article h4 { font-size: 1rem; margin: 1.4rem 0 .4rem; }

.article p { margin: .7rem 0; }

.article a { color: var(--accent); }
.article a:hover { text-decoration-thickness: 2px; }

.article ul, .article ol { padding-left: 1.5rem; }
.article li { margin: .3rem 0; }

.article hr {
  border: none;
  border-top: 2px solid var(--ligne);
  margin: 2.5rem auto;
  width: 40%;
}

.article strong { color: #12202d; }

/* citations = messages / encadrés à dire */
.article blockquote {
  margin: 1.3rem 0;
  padding: .9rem 1.2rem;
  background: var(--ocre-clair);
  border-left: 4px solid var(--ocre);
  border-radius: 0 6px 6px 0;
  font-size: 1.02em;
}
.article blockquote p { margin: .35rem 0; }

.article code {
  background: #eeeae0;
  border-radius: 4px;
  padding: .1em .35em;
  font-size: .88em;
}

.article pre {
  background: var(--encre);
  color: #e8edf2;
  border-radius: 8px;
  padding: 1rem 1.2rem;
  overflow-x: auto;
  font-size: .85rem;
  line-height: 1.55;
}
.article pre code { background: none; padding: 0; color: inherit; }

/* tableaux */
.table-wrap { overflow-x: auto; margin: 1.1rem 0; }

.article table {
  border-collapse: collapse;
  width: 100%;
  font-size: .92rem;
  background: var(--blanc);
  border: 1px solid var(--ligne);
}

.article th {
  background: var(--accent-clair);
  color: var(--encre);
  text-align: left;
  font-weight: 650;
  padding: .55rem .7rem;
  border-bottom: 2px solid var(--accent);
}

.article td {
  padding: .5rem .7rem;
  border-top: 1px solid var(--ligne);
  vertical-align: top;
}

.article tbody tr:nth-child(even) { background: #fbfaf7; }

/* cases à cocher des consignes */
.article input[type="checkbox"] { margin-right: .45rem; }

/* ---------- menu flottant droit ---------- */

.menu-flottant {
  position: sticky;
  top: 4.4rem;
  align-self: start;
  max-height: calc(100vh - 6rem);
  overflow-y: auto;
  padding: 1rem 1.1rem;
  background: var(--blanc);
  border: 1px solid var(--ligne);
  border-radius: 10px;
  box-shadow: 0 2px 10px rgba(28, 43, 57, .06);
  font-size: .84rem;
}

.menu-titre {
  margin: 0 0 .5rem;
  font-weight: 700;
  font-size: .78rem;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--encre-doux);
}

.menu-flottant ul { list-style: none; margin: 0; padding: 0; }
.menu-flottant ul ul { padding-left: .85rem; margin-top: .1rem; }

.menu-flottant li { margin: .18rem 0; }

.menu-flottant a {
  display: block;
  color: var(--encre-doux);
  text-decoration: none;
  padding: .18rem .45rem;
  border-left: 2px solid transparent;
  border-radius: 0 4px 4px 0;
  line-height: 1.35;
}
.menu-flottant a:hover { color: var(--accent); background: var(--accent-clair); }
.menu-flottant a.actif {
  color: var(--accent);
  font-weight: 650;
  border-left-color: var(--accent);
  background: var(--accent-clair);
}

.menu-haut {
  display: block;
  margin-top: .9rem;
  padding-top: .7rem;
  border-top: 1px solid var(--ligne);
  color: var(--encre-doux);
  text-decoration: none;
  font-size: .8rem;
}
.menu-haut:hover { color: var(--accent); }

/* ---------- accueil ---------- */

.page-accueil {
  max-width: 52rem;
  margin: 0 auto;
  padding: 3rem 1.25rem 4rem;
}

.hero h1 {
  font-family: var(--serif);
  font-size: 2.3rem;
  line-height: 1.22;
  margin: 0 0 1rem;
}

.hero-p {
  font-size: 1.08rem;
  color: var(--encre-doux);
  max-width: 42rem;
  border-left: 4px solid var(--ocre);
  padding-left: 1rem;
}

.seances h2, .trois-questions h2 {
  font-family: var(--serif);
  font-size: 1.4rem;
  color: var(--accent);
  margin: 2.8rem 0 1rem;
}

.carte {
  background: var(--blanc);
  border: 1px solid var(--ligne);
  border-radius: 12px;
  padding: 1.4rem 1.6rem;
  box-shadow: 0 2px 12px rgba(28, 43, 57, .06);
}

.carte-tete { display: flex; gap: 1.1rem; align-items: flex-start; }

.carte-num {
  flex: none;
  width: 2.6rem;
  height: 2.6rem;
  border-radius: 50%;
  background: var(--encre);
  color: #fff;
  font-family: var(--serif);
  font-size: 1.3rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.carte h3 { margin: .1rem 0 .2rem; font-size: 1.15rem; }
.carte-sous { margin: 0; color: var(--encre-doux); font-size: .92rem; }

.carte-actions { display: flex; gap: .7rem; margin: 1.1rem 0 .4rem; flex-wrap: wrap; }

.btn {
  display: inline-block;
  padding: .55rem 1.2rem;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 600;
  font-size: .95rem;
}
.btn-plein { background: var(--accent); color: #fff; }
.btn-plein:hover { background: #0c4a72; }
.btn-ligne { border: 2px solid var(--accent); color: var(--accent); }
.btn-ligne:hover { background: var(--accent-clair); }

.carte-docs { font-size: .88rem; color: var(--encre-doux); margin: .5rem 0 0; }
.carte-docs a { color: var(--accent); }

.a-venir { color: var(--encre-doux); font-size: .9rem; font-style: italic; }

.trois-questions ol {
  background: var(--blanc);
  border: 1px solid var(--ligne);
  border-radius: 12px;
  margin: 0;
  padding: 1.2rem 1.2rem 1.2rem 2.6rem;
  font-family: var(--serif);
  font-size: 1.12rem;
}
.trois-questions li { margin: .45rem 0; }

/* ---------- pied ---------- */

.pied {
  border-top: 1px solid var(--ligne);
  padding: 1.2rem;
  text-align: center;
  color: var(--encre-doux);
  font-size: .82rem;
}

/* ---------- écrans étroits ---------- */

@media (max-width: 66rem) {
  .page-lineaire { grid-template-columns: minmax(0, 1fr); }
  .menu-flottant { display: none; }
}

/* ---------- impression ---------- */

@media print {
  .bandeau, .menu-flottant, .pied { display: none; }
  body { background: #fff; font-size: 11pt; }
  .page-lineaire { display: block; padding: 0; }
  .article pre { background: #f4f4f4; color: #222; }
}