:root {
  --bg: #f6f7f8;
  --panel: #fff;
  --text: #1f2933;
  --muted: #5c6973;
  --line: #dfe5e8;
  --accent: #244e68;
  --max: 1160px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin:0;
  font-family: Arial, Helvetica, sans-serif;
  color:var(--text);
  background:var(--bg);
  line-height:1.65;
}
a { color:var(--accent); }
.wrap { width:min(var(--max), calc(100% - 36px)); margin:0 auto; }
.skip-link { position:absolute; left:-9999px; }
.skip-link:focus { left:16px; top:16px; background:#fff; padding:10px 14px; z-index:100; }

.site-header {
  background:#fff;
  border-bottom:1px solid var(--line);
  position:sticky;
  top:0;
  z-index:30;
}
.header-inner {
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:24px;
  min-height:76px;
}
.brand { color:var(--text); text-decoration:none; }
.brand-text { display:flex; flex-direction:column; line-height:1.1; }
.brand-text strong { letter-spacing:.08em; font-size:.94rem; }
.brand-text small { color:var(--muted); margin-top:5px; font-size:.78rem; }
.main-nav { display:flex; flex-wrap:wrap; justify-content:flex-end; gap:4px 13px; }
.main-nav a {
  text-decoration:none;
  color:var(--muted);
  font-size:.88rem;
  padding:8px 0;
  border-bottom:2px solid transparent;
}
.main-nav a:hover, .main-nav a.active { color:var(--accent); border-bottom-color:var(--accent); }

.hero {
  background:linear-gradient(180deg,#fff,#eef2f4);
  border-bottom:1px solid var(--line);
}
.hero-inner { max-width:900px; padding:70px 0 58px; }
.eyebrow, .section-kicker {
  margin:0 0 10px;
  font-size:.78rem;
  letter-spacing:.15em;
  font-weight:700;
  color:#52758b;
}
h1 {
  margin:0;
  font-size:clamp(2.2rem,4.5vw,4rem);
  line-height:1.05;
  letter-spacing:-.035em;
}
.lead {
  margin:22px 0 0;
  font-size:1.18rem;
  color:var(--muted);
  max-width:820px;
}
.article { max-width:900px; padding:54px 0 78px; }
.article-wide { max-width:1040px; }
.content-section {
  padding:0 0 36px;
  margin:0 0 36px;
  border-bottom:1px solid var(--line);
}
.content-section:last-child { border-bottom:0; }
.content-section h2 {
  margin:0 0 18px;
  font-size:clamp(1.55rem,2.6vw,2.15rem);
  line-height:1.18;
}
.content-section p { margin:0 0 16px; }
.note-box {
  padding:28px 30px !important;
  background:#edf2f4;
  border:1px solid #d5e0e5 !important;
  border-radius:10px;
}

.site-footer { background:#fff; border-top:1px solid var(--line); }
.footer-inner { display:flex; justify-content:space-between; gap:28px; padding:32px 0; }
.footer-inner p { margin:5px 0 0; color:var(--muted); }
.legal-note { font-size:.8rem; max-width:660px; }
.footer-links { display:flex; flex-direction:column; align-items:flex-end; gap:6px; }

/* Home */
.v4-hero {
  color:#fff;
  background:
    radial-gradient(circle at 80% 18%, rgba(95,145,176,.28), transparent 26%),
    linear-gradient(135deg,#0b141b 0%,#152a38 58%,#24485c 100%);
  overflow:hidden;
}
.v4-hero-grid {
  display:grid;
  grid-template-columns:minmax(0,1.08fr) minmax(360px,.92fr);
  gap:64px;
  align-items:center;
  min-height:720px;
  padding-top:72px;
  padding-bottom:72px;
}
.v4-hero .eyebrow { color:#9fc1d4; }
.v4-hero h1 {
  font-size:clamp(3.1rem,6vw,6rem);
  line-height:.95;
  letter-spacing:-.055em;
}
.v4-hero h1 span { font-weight:300; color:#c6dce8; }
.v4-intro {
  max-width:760px;
  margin:28px 0 0;
  font-size:clamp(1.16rem,1.8vw,1.4rem);
  line-height:1.62;
  color:#edf4f8;
}
.v4-intro.small { font-size:1.03rem; color:#c4d2da; }
.hero-actions { margin-top:34px; display:flex; flex-wrap:wrap; gap:18px 26px; align-items:center; }
.primary-link {
  display:inline-flex; align-items:center; justify-content:center;
  min-height:46px; padding:0 18px;
  background:#f1f4f5; color:#122432;
  border-radius:5px; text-decoration:none; font-weight:700;
}
.primary-link.dark { background:#17364a; color:#fff; }
.text-link { color:#d7e5ed; text-decoration:none; }
.subtle-link { color:#2d5b76; font-weight:700; text-decoration:none; }
.subtle-link.light { color:#d4e6f0; }
.v4-hero-stack { position:relative; min-height:520px; }
.v4-hero-stack img {
  position:absolute; width:92%; border-radius:20px;
  box-shadow:0 30px 75px rgba(0,0,0,.34);
}
.v4-hero-stack img:first-child { top:20px; left:0; transform:rotate(-4deg); }
.v4-hero-stack img:last-child { top:220px; right:0; transform:rotate(4deg); }

.manifesto { padding:96px 0; background:#f4f3ef; }
.manifesto-grid { display:grid; grid-template-columns:90px 1fr; gap:38px; }
.manifesto-big { font-family:Georgia,serif; font-size:8rem; line-height:.7; color:#b3bdc2; }
.manifesto h2, .origin-section h2, .epochs h2, .warp-section h2, .alive-section h2, .explore-section h2 {
  margin:0 0 24px;
  font-size:clamp(2rem,4vw,3.35rem);
  line-height:1.08;
  letter-spacing:-.035em;
}
.big-copy { max-width:930px; font-size:clamp(1.13rem,2vw,1.34rem); line-height:1.75; color:#3d4951; }

.origin-section { padding:88px 0; background:#fff; }
.origin-grid, .warp-grid, .alive-grid {
  display:grid; grid-template-columns:1fr 1fr; gap:72px; align-items:center;
}
.origin-copy p, .warp-copy p, .alive-copy p { color:#4b5962; font-size:1.06rem; line-height:1.72; }

.visual-card { margin:0; }
.visual-card img {
  display:block; width:100%; height:auto; border-radius:18px;
  box-shadow:0 20px 55px rgba(22,38,48,.12);
}
.visual-card figcaption { margin-top:12px; color:#77838a; font-size:.82rem; }
.visual-card.dark figcaption { color:#afbdc6; }

.epochs { padding:92px 0 104px; background:#eef1f2; }
.epoch-grid {
  margin-top:44px;
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  border-top:1px solid #cfd7dc;
  border-left:1px solid #cfd7dc;
}
.epoch-grid article {
  min-height:270px;
  padding:28px;
  background:rgba(255,255,255,.48);
  border-right:1px solid #cfd7dc;
  border-bottom:1px solid #cfd7dc;
}
.epoch-grid article span { display:block; margin-bottom:34px; color:#8c9ba5; font-size:.75rem; letter-spacing:.16em; }
.epoch-grid article h3 { margin:0 0 12px; font-size:1.45rem; }
.epoch-grid article p { margin:0; color:#58666f; }

.warp-section { padding:100px 0; background:#172735; color:#fff; }
.warp-copy .section-kicker { color:#9abbd0; }
.warp-copy h2 { color:#fff; }
.warp-copy p { color:#d4e0e7; }

.alive-section { padding:100px 0; background:#f6f7f7; }

.explore-section { padding:90px 0 110px; background:#fff; }
.explore-intro { max-width:760px; color:#58646c; font-size:1.05rem; margin-bottom:40px; }
.story-links { border-top:1px solid #dfe5e8; }
.story-links a {
  display:grid;
  grid-template-columns:52px 220px 1fr;
  gap:18px;
  align-items:center;
  padding:22px 0;
  border-bottom:1px solid #dfe5e8;
  text-decoration:none;
  color:#24333d;
}
.story-links span { color:#91a0aa; font-size:.78rem; }
.story-links strong { font-size:1.04rem; }
.story-links em { color:#67747d; font-style:normal; }

.two-col-story {
  display:grid;
  grid-template-columns:1fr .9fr;
  gap:58px;
  align-items:center;
}
.two-col-story.reverse > div { order:2; }
.two-col-story.reverse > img { order:1; }
.two-col-story img {
  width:100%;
  border-radius:16px;
  box-shadow:0 18px 42px rgba(26,43,54,.10);
}

@media (max-width: 1040px) {
  .site-header { position:static; }
  .header-inner { align-items:flex-start; flex-direction:column; padding:16px 0; }
  .main-nav { justify-content:flex-start; }
}
@media (max-width: 980px) {
  .v4-hero-grid, .origin-grid, .warp-grid, .alive-grid, .two-col-story { grid-template-columns:1fr; }
  .v4-hero-grid { min-height:auto; }
  .v4-hero-stack { min-height:520px; max-width:700px; }
  .epoch-grid { grid-template-columns:repeat(2,minmax(0,1fr)); }
  .two-col-story.reverse > div, .two-col-story.reverse > img { order:initial; }
}
@media (max-width: 620px) {
  .wrap { width:min(var(--max), calc(100% - 24px)); }
  .v4-hero h1 { font-size:3rem; }
  .v4-hero-grid { padding-top:50px; padding-bottom:54px; gap:34px; }
  .v4-hero-stack { min-height:360px; }
  .v4-hero-stack img:last-child { top:145px; }
  .manifesto { padding:65px 0; }
  .manifesto-grid { grid-template-columns:1fr; gap:12px; }
  .manifesto-big { font-size:5rem; }
  .origin-section,.epochs,.warp-section,.alive-section,.explore-section { padding:66px 0; }
  .epoch-grid { grid-template-columns:1fr; }
  .epoch-grid article { min-height:0; }
  .story-links a { grid-template-columns:34px 1fr; }
  .story-links em { grid-column:2; }
  .footer-inner { flex-direction:column; }
  .footer-links { align-items:flex-start; }
}


/* ============================================================
   Navigation responsive — ordinateur, tablette et smartphone
   ============================================================ */

.menu-toggle {
  display: none;
  appearance: none;
  border: 0;
  background: transparent;
  color: var(--text);
  font: inherit;
  cursor: pointer;
}

@media (max-width: 1040px) {
  .site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    box-shadow: 0 4px 18px rgba(18, 35, 45, .07);
  }

  .header-inner {
    position: relative;
    min-height: 68px;
    padding: 10px 0;
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 12px;
  }

  .brand {
    min-width: 0;
  }

  .brand-text strong {
    font-size: .88rem;
    letter-spacing: .065em;
  }

  .brand-text small {
    max-width: 520px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .menu-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 9px;
    min-width: 82px;
    min-height: 44px;
    padding: 8px 12px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #fff;
    font-size: .9rem;
    font-weight: 700;
  }

  .menu-toggle-lines,
  .menu-toggle-lines::before,
  .menu-toggle-lines::after {
    display: block;
    width: 20px;
    height: 2px;
    border-radius: 2px;
    background: var(--accent);
    transition: transform .2s ease, opacity .2s ease;
  }

  .menu-toggle-lines {
    position: relative;
  }

  .menu-toggle-lines::before,
  .menu-toggle-lines::after {
    content: "";
    position: absolute;
    left: 0;
  }

  .menu-toggle-lines::before { top: -6px; }
  .menu-toggle-lines::after { top: 6px; }

  .menu-toggle.is-open .menu-toggle-lines {
    background: transparent;
  }

  .menu-toggle.is-open .menu-toggle-lines::before {
    top: 0;
    transform: rotate(45deg);
  }

  .menu-toggle.is-open .menu-toggle-lines::after {
    top: 0;
    transform: rotate(-45deg);
  }

  .main-nav {
    display: none;
    grid-column: 1 / -1;
    width: 100%;
    margin-top: 4px;
    padding: 8px 0 12px;
    border-top: 1px solid var(--line);
    background: #fff;
  }

  .main-nav.is-open {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 4px 10px;
  }

  .main-nav a {
    display: flex;
    align-items: center;
    min-height: 44px;
    padding: 9px 10px;
    border-bottom: 0;
    border-radius: 7px;
    font-size: .94rem;
    line-height: 1.25;
  }

  .main-nav a:hover,
  .main-nav a:focus-visible {
    background: #eef3f5;
    outline: none;
  }

  .main-nav a.active {
    background: #e8f0f4;
    color: var(--accent);
    border-bottom: 0;
    font-weight: 700;
  }
}

@media (max-width: 620px) {
  .header-inner {
    min-height: 62px;
  }

  .brand-text strong {
    font-size: .80rem;
  }

  .brand-text small {
    display: none;
  }

  .menu-toggle {
    min-width: 48px;
    width: 48px;
    padding: 0;
  }

  .menu-toggle-text {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
    white-space: nowrap;
  }

  .main-nav.is-open {
    grid-template-columns: 1fr;
    max-height: calc(100vh - 76px);
    overflow-y: auto;
    overscroll-behavior: contain;
    padding-bottom: 16px;
  }

  .main-nav a {
    min-height: 46px;
    padding: 10px 12px;
    font-size: 1rem;
  }

  .hero-inner {
    padding: 48px 0 42px;
  }

  h1 {
    font-size: clamp(2rem, 10vw, 2.75rem);
  }

  .lead {
    font-size: 1.06rem;
  }

  .v4-hero h1 {
    font-size: clamp(2.45rem, 12vw, 3.3rem);
    line-height: 1;
  }

  .v4-intro {
    font-size: 1.08rem;
  }

  .v4-hero-stack {
    min-height: 315px;
  }

  .v4-hero-stack img:first-child {
    width: 94%;
  }

  .v4-hero-stack img:last-child {
    top: 128px;
    width: 94%;
  }

  .content-section {
    margin-bottom: 28px;
    padding-bottom: 28px;
  }

  .note-box {
    padding: 22px 20px !important;
  }
}

/* Sans JavaScript, le menu reste visible : pas de page bloquée. */
.no-js .menu-toggle { display: none !important; }


.footer-person-link {
  color: inherit;
  text-decoration: none;
}
.footer-person-link:hover,
.footer-person-link:focus-visible {
  text-decoration: underline;
}