/* Site public (accueil, téléchargement). Aucune ressource externe : ni
   police ni script tiers, cohérent avec ce que la page promet. */
:root {
  --ink: #14213d;
  --text: #2b3550;
  --muted: #5a6478;
  --paper: #fbfcfe;
  --line: #d9dfea;
  --blue: #1457b8;
  --blue-dark: #0f4594;
  --blue-tint: #e8f0fb;
  --green: #2f7d5b;
  --green-tint: #e6f2ec;
  --serif: "Iowan Old Style", "Charter", "Bitstream Charter", "Sitka Text", Cambria, Georgia, serif;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--text);
  font: 17px/1.6 var(--sans);
}
a { color: var(--blue); }
a:focus-visible, .button:focus-visible { outline: 3px solid var(--blue); outline-offset: 3px; }

.wrap { max-width: 1080px; margin: 0 auto; padding: 0 24px; }

/* --- en-tête --- */
.site-head { border-bottom: 1px solid var(--line); background: #fff; }
.site-head .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 64px; flex-wrap: wrap; }
.brand { font: 600 19px/1 var(--serif); color: var(--ink); text-decoration: none; letter-spacing: 0.01em; }
.site-head nav { display: flex; gap: 20px; flex-wrap: wrap; }
.site-head nav a { color: var(--text); text-decoration: none; font-size: 15px; }
.site-head nav a:hover { color: var(--blue); text-decoration: underline; }
.site-head .wrap { padding-top: 10px; padding-bottom: 10px; }

/* --- titres et texte --- */
h1, h2, h3 { font-family: var(--serif); color: var(--ink); font-weight: 600; line-height: 1.2; }
h1 { font-size: clamp(34px, 5.2vw, 56px); margin: 0 0 20px; letter-spacing: -0.01em; max-width: 21ch; }
h2 { font-size: clamp(26px, 3.4vw, 36px); margin: 0 0 14px; }
h3 { font-size: 21px; margin: 0 0 8px; }
p { margin: 0 0 14px; max-width: 66ch; }
.lead { font-size: 20px; color: var(--muted); max-width: 58ch; }

section { padding: 72px 0; }
section + section { border-top: 1px solid var(--line); }

/* --- boutons --- */
.actions { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 28px; }
.button {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 50px; padding: 12px 24px; border-radius: 8px;
  font: 600 17px/1.2 var(--sans); text-decoration: none;
  border: 2px solid var(--blue);
}
.button.primary { background: var(--blue); color: #fff; }
.button.primary:hover { background: var(--blue-dark); border-color: var(--blue-dark); }
.button.secondary { background: #fff; color: var(--blue); }
.button.secondary:hover { background: var(--blue-tint); }

/* --- accueil --- */
.hero { padding: 80px 0 64px; }
.hero .facts { display: flex; flex-wrap: wrap; gap: 8px 28px; margin: 32px 0 0; padding: 0; list-style: none; color: var(--muted); font-size: 15px; }
.hero .facts li::before { content: ""; display: inline-block; width: 8px; height: 8px; border-radius: 50%; background: var(--green); margin-right: 9px; vertical-align: 2px; }

.tasks { display: grid; grid-template-columns: repeat(3, 1fr); gap: 36px; margin-top: 32px; }
.tasks div { border-top: 3px solid var(--ink); padding-top: 16px; }
.tasks p { font-size: 16px; }

.modes { display: grid; grid-template-columns: 1fr 1fr; gap: 0; margin-top: 32px; border: 1px solid var(--line); border-radius: 10px; overflow: hidden; background: #fff; }
.modes > div { padding: 28px; }
.modes > div + div { border-left: 1px solid var(--line); }
.modes .who { color: var(--muted); font-size: 15px; margin-bottom: 12px; }
.modes ul { margin: 0 0 20px; padding-left: 20px; }
.modes li { margin: 4px 0; }
.modes li.no { color: var(--muted); }

/* --- schéma d'architecture --- */
.archi { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 0.85fr) minmax(0, 1fr); gap: 14px 0; margin-top: 36px; }
.archi-head { font: 600 15px/1.2 var(--sans); color: var(--muted); text-transform: uppercase; letter-spacing: 0.05em; padding: 0 18px 4px; }
.archi-head.flow-head { text-align: center; }
.archi-head.paris-head { color: var(--blue); }
.client { background: #fff; border: 2px solid var(--ink); border-radius: 12px; padding: 16px 18px 6px; }
.client .tag { font: 600 18px/1.2 var(--serif); color: var(--ink); margin: 0 0 12px; }
.server { background: var(--blue-tint); border: 2px solid var(--blue); border-radius: 12px; padding: 16px 18px 6px; display: flex; flex-direction: column; justify-content: center; }
.box { background: #fff; border: 1px solid var(--line); border-radius: 8px; padding: 12px 14px; margin-bottom: 10px; font-size: 15px; line-height: 1.45; }
.box strong { display: block; color: var(--ink); font-size: 15px; }
.box span { color: var(--muted); font-size: 14px; }
.gateway { border-color: var(--blue); }
.flow { display: flex; flex-direction: column; justify-content: center; padding: 0 16px; text-align: center; font-size: 14px; color: var(--text); }
.flow p { margin: 8px 0 0; line-height: 1.45; }
.flow strong { color: var(--ink); }
.flow .no { color: var(--green); font-weight: 600; font-size: 13px; }
.flow .arrow { height: 2px; background: var(--ink); position: relative; margin: 0 4px; }
.flow .arrow::after { content: ""; position: absolute; right: -2px; top: -5px; border: 6px solid transparent; border-left: 9px solid var(--ink); border-right: 0; }
.shared { grid-column: 1 / -1; background: var(--blue-tint); border: 2px solid var(--blue); border-radius: 12px; padding: 16px 20px; font-size: 15px; }
.shared strong { color: var(--ink); }

.legend { margin-top: 18px; font-size: 15px; color: var(--muted); }
.external { margin-top: 20px; border: 2px dashed var(--muted); border-radius: 12px; padding: 18px 22px; background: #fff; }
.external h3 { font-size: 18px; margin-bottom: 6px; }
.external p { font-size: 15px; margin: 0; max-width: 80ch; }

/* --- confidentialité --- */
.privacy { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 28px; margin-top: 28px; }
.privacy > div { padding-left: 16px; border-left: 3px solid var(--green); }
.privacy h3 { font-size: 19px; }
.privacy p { font-size: 16px; }
.note { margin-top: 28px; background: var(--green-tint); border-radius: 8px; padding: 16px 20px; font-size: 16px; max-width: none; }

/* --- téléchargement --- */
.downloads { list-style: none; padding: 0; margin: 28px 0 0; max-width: 640px; }
.downloads li { border: 1px solid var(--line); border-radius: 10px; background: #fff; padding: 20px 22px; margin-bottom: 14px; }
.downloads .row { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
.downloads h3 { margin: 0; }
.downloads p { font-size: 15px; color: var(--muted); margin: 10px 0 0; }

/* --- pied de page --- */
.site-foot { border-top: 1px solid var(--line); padding: 28px 0 40px; color: var(--muted); font-size: 14px; }
.site-foot .wrap { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
.foot-links { display: flex; gap: 20px; flex-wrap: wrap; }

/* --- téléphones et tablettes --- */
@media (max-width: 860px) {
  section { padding: 56px 0; }
  .hero { padding: 56px 0 48px; }
  .tasks, .privacy { grid-template-columns: 1fr; gap: 24px; }
  .modes { grid-template-columns: 1fr; }
  .modes > div + div { border-left: 0; border-top: 1px solid var(--line); }
  .archi { grid-template-columns: 1fr; gap: 0; }
  .archi-head { display: none; }
  .flow { padding: 10px 0 10px 28px; text-align: left; position: relative; }
  .flow .arrow { position: absolute; left: 12px; top: 0; bottom: 0; width: 2px; height: auto; margin: 0; }
  .flow .arrow::after { right: -5px; top: auto; bottom: -2px; border: 6px solid transparent; border-top: 9px solid var(--ink); border-bottom: 0; }
  .server { margin-bottom: 22px; }
}
@media (max-width: 480px) {
  body { font-size: 16px; }
  .site-head nav .section-link { display: none; }
  .wrap { padding: 0 16px; }
  .lead { font-size: 18px; }
  .button { width: 100%; }
}