:root {
  --navy-950: #0a1730;
  --navy-900: #0d1d3d;
  --navy-800: #142a52;
  --navy-700: #1c3a6e;
  --red: #dc2626;
  --red-dark: #b91c1c;
  --amber: #f59e0b;
  --ink: #0f172a;
  --muted: #475569;
  --line: #e2e8f0;
  --soft: #f1f5f9;
  --white: #ffffff;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(10, 23, 48, .10);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 76px; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--white);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; }
.wrap { width: min(1120px, 100% - 40px); margin-inline: auto; }

/* Navigation */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255, 255, 255, .94);
  backdrop-filter: saturate(1.4) blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav-row { display: flex; align-items: center; justify-content: space-between; gap: 16px; height: 68px; }
.brand img { height: 34px; width: auto; }
.menu { display: flex; align-items: center; gap: 26px; }
.menu a { text-decoration: none; font-size: 15px; font-weight: 600; color: var(--muted); }
.menu a:hover { color: var(--navy-700); }
.menu .btn { color: var(--white); }
.burger { display: none; background: none; border: 0; padding: 8px; cursor: pointer; }
.burger span { display: block; width: 24px; height: 2px; background: var(--navy-800); margin: 5px 0; border-radius: 2px; }

/* Boutons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 11px 20px; border-radius: 10px; font-weight: 700; font-size: 15px;
  text-decoration: none; border: 2px solid transparent; cursor: pointer;
  transition: transform .15s ease, background .15s ease, border-color .15s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn-primary { background: var(--red); color: var(--white); }
.btn-primary:hover { background: var(--red-dark); }
.btn-ghost { border-color: rgba(255, 255, 255, .45); color: var(--white); }
.btn-ghost:hover { border-color: var(--white); }
.btn-outline { border-color: var(--navy-700); color: var(--navy-700); }
.btn-outline:hover { background: var(--navy-700); color: var(--white); }

/* Hero */
.hero {
  background:
    radial-gradient(900px 400px at 85% 10%, rgba(220, 38, 38, .22), transparent 60%),
    linear-gradient(135deg, var(--navy-950), var(--navy-800));
  color: var(--white);
  padding: 76px 0 84px;
  overflow: hidden;
}
.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 48px; align-items: center; }
.kicker {
  display: inline-block; font-size: 12.5px; font-weight: 800; letter-spacing: .12em; text-transform: uppercase;
  color: #fecaca; background: rgba(220, 38, 38, .18); border: 1px solid rgba(254, 202, 202, .35);
  padding: 6px 12px; border-radius: 999px;
}
.hero h1 { font-size: clamp(32px, 4.6vw, 54px); line-height: 1.08; margin: 18px 0 16px; letter-spacing: -.02em; }
.hero h1 em { font-style: normal; color: #fca5a5; }
.hero p.lead { font-size: 19px; color: #cbd5e1; max-width: 560px; margin: 0 0 28px; }
.cta { display: flex; flex-wrap: wrap; gap: 12px; }
.hero-note { margin-top: 22px; font-size: 13.5px; color: #94a3b8; }

.plot {
  background: rgba(8, 15, 32, .72);
  border: 1px solid rgba(148, 163, 184, .25);
  border-radius: 18px; padding: 18px 18px 12px;
  box-shadow: 0 24px 60px rgba(0, 0, 0, .35);
}
.plot svg { width: 100%; height: auto; display: block; }
.plot-legend { display: flex; flex-wrap: wrap; gap: 14px; font-size: 12.5px; color: #cbd5e1; padding: 6px 4px 2px; }
.plot-legend i { display: inline-block; width: 18px; height: 3px; border-radius: 2px; margin-right: 6px; vertical-align: middle; }
.draw { stroke-dasharray: 1400; stroke-dashoffset: 1400; animation: draw 2.4s ease forwards .2s; }
.draw.slow { animation-delay: .7s; }
.fade { opacity: 0; animation: fade .8s ease forwards 2.2s; }
@keyframes draw { to { stroke-dashoffset: 0; } }
@keyframes fade { to { opacity: 1; } }

/* Sections */
section { padding: 84px 0; }
section.alt { background: var(--soft); }
.eyebrow { font-size: 13px; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; color: var(--red-dark); }
h2 { font-size: clamp(26px, 3.2vw, 38px); line-height: 1.15; margin: 10px 0 14px; letter-spacing: -.015em; color: var(--navy-900); }
.sub { color: var(--muted); font-size: 18px; max-width: 720px; margin: 0 0 42px; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.card {
  background: var(--white); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 28px; box-shadow: var(--shadow);
}
.card h3 { margin: 0 0 6px; font-size: 22px; color: var(--navy-900); }
.tag {
  display: inline-block; font-size: 11.5px; font-weight: 800; letter-spacing: .08em; text-transform: uppercase;
  padding: 4px 9px; border-radius: 6px; margin-bottom: 14px;
}
.tag.ok { background: #dcfce7; color: #166534; }
.tag.alpha { background: #fee2e2; color: #991b1b; }
.tag.dev { background: #dbeafe; color: #1e40af; }
.card.blood {
  margin-top: 24px; display: grid; grid-template-columns: 1.1fr .9fr; gap: 24px; align-items: center;
  border-left: 5px solid var(--red);
}
.card.blood .lanes { margin-top: 0; justify-content: flex-end; }
.card ul { margin: 14px 0 0; padding: 0; list-style: none; }
.card li { position: relative; padding-left: 26px; margin: 9px 0; color: var(--muted); }
.card li::before {
  content: ""; position: absolute; left: 0; top: 9px; width: 12px; height: 12px; border-radius: 50%;
  background: var(--red); box-shadow: 0 0 0 4px rgba(220, 38, 38, .15);
}
.lanes { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.lanes span {
  font-weight: 800; font-size: 13px; padding: 5px 12px; border-radius: 8px;
  background: var(--navy-900); color: var(--white);
}
.lanes span.k { background: var(--red-dark); }

.principle { background: var(--white); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; }
.principle .n {
  width: 38px; height: 38px; border-radius: 10px; background: var(--navy-800); color: var(--white);
  display: grid; place-items: center; font-weight: 800; margin-bottom: 14px;
}
.principle h3 { margin: 0 0 6px; font-size: 18px; color: var(--navy-900); }
.principle p { margin: 0; color: var(--muted); font-size: 15px; }

.steps { counter-reset: s; display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }
.step { background: var(--white); border-radius: var(--radius); padding: 26px; border: 1px solid var(--line); }
.step::before {
  counter-increment: s; content: counter(s);
  display: grid; place-items: center; width: 36px; height: 36px; border-radius: 50%;
  background: var(--red); color: var(--white); font-weight: 800; margin-bottom: 14px;
}
.step h3 { margin: 0 0 6px; font-size: 18px; color: var(--navy-900); }
.step p { margin: 0; color: var(--muted); font-size: 15px; }

.callout {
  margin-top: 36px; padding: 18px 22px; border-radius: 12px;
  background: #fef3c7; border: 1px solid #fcd34d; color: #78350f; font-size: 15px;
}

.contact {
  background: linear-gradient(135deg, var(--navy-950), var(--navy-800)); color: var(--white); text-align: center;
}
.contact h2 { color: var(--white); }
.contact p { color: #cbd5e1; max-width: 640px; margin: 0 auto 26px; font-size: 18px; }
.contact .cta { justify-content: center; }
.contact .mail-line { font-size: 20px; margin-bottom: 22px; }
.contact .mail-line b { color: var(--white); user-select: all; }
.contact .mail-help { font-size: 14.5px; color: #94a3b8; margin: 14px auto 0; }
.contact .mail-help a { color: #fecaca; }
.contact .btn-ghost { background: transparent; font-family: inherit; }

footer { background: var(--navy-950); color: #94a3b8; padding: 30px 0; font-size: 14px; }
.foot-row { display: flex; flex-wrap: wrap; gap: 14px 28px; justify-content: space-between; align-items: center; }
footer a { text-decoration: none; }
footer a:hover { color: var(--white); }
.foot-links { display: flex; flex-wrap: wrap; gap: 18px; }

/* Mobile */
@media (max-width: 920px) {
  .hero-grid { grid-template-columns: 1fr; gap: 36px; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: 1fr; }
  .grid-2 { grid-template-columns: 1fr; }
  .card.blood { grid-template-columns: 1fr; }
  .card.blood .lanes { justify-content: flex-start; margin-top: 4px; }
}
@media (max-width: 760px) {
  section { padding: 60px 0; }
  .hero { padding: 48px 0 56px; }
  .burger { display: block; }
  .menu {
    position: absolute; left: 0; right: 0; top: 68px; background: var(--white);
    flex-direction: column; align-items: stretch; gap: 0; padding: 8px 20px 18px;
    border-bottom: 1px solid var(--line); display: none;
  }
  .menu.open { display: flex; }
  .menu a { padding: 13px 4px; border-bottom: 1px solid var(--line); }
  .menu .btn { margin-top: 12px; border-bottom: 0; }
  .grid-4 { grid-template-columns: 1fr; }
  .hero p.lead { font-size: 17px; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .draw { animation: none; stroke-dashoffset: 0; }
  .fade { animation: none; opacity: 1; }
  .btn { transition: none; }
}