/* =================================================================
   14 Bis — Réseau des Ingénieurs France-Brésil
   Feuille de styles principale (vanilla, mobile-first)
   NB : les variables de charte gardent le préfixe --aifb-* (ancien nom).
   Purement interne/invisible : conservé pour éviter un renommage à risque.
   ================================================================= */

/* ---------- 1. Variables (charte) ---------- */
:root {
  --aifb-navy: #0B1F3A;
  --aifb-blue-france: #0055A4;
  --aifb-green-brazil: #009739;
  --aifb-yellow-brazil: #FFDF00;
  --aifb-red-france: #EF4135;

  --aifb-background: #F8FAFC;
  --aifb-background-warm: #F5F1E8;
  --aifb-white: #FFFFFF;

  --aifb-text: #1F2933;
  --aifb-text-muted: #64748B;
  --aifb-border: #E2E8F0;

  --aifb-gradient-main: linear-gradient(135deg, #0B1F3A 0%, #0055A4 48%, #009739 100%);
  --aifb-gradient-accent: linear-gradient(90deg, #0055A4 0%, #FFFFFF 38%, #009739 76%, #FFDF00 100%);

  --container: 1180px;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow-sm: 0 1px 2px rgba(11, 31, 58, 0.06);
  --shadow-md: 0 10px 30px rgba(11, 31, 58, 0.08);
  --shadow-lg: 0 20px 50px rgba(11, 31, 58, 0.14);
  --header-h: 72px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);

  --font: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

/* ---------- 2. Reset léger ---------- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; }
html { scroll-behavior: smooth; scroll-padding-top: calc(var(--header-h) + 16px); -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--font);
  color: var(--aifb-text);
  background: var(--aifb-background);
  line-height: 1.6;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
ul { list-style: none; padding: 0; }
button { font-family: inherit; cursor: pointer; }
:focus-visible { outline: 3px solid var(--aifb-blue-france); outline-offset: 2px; border-radius: 4px; }

/* ---------- 3. Layout ---------- */
.container { width: 100%; max-width: var(--container); margin-inline: auto; padding-inline: 22px; }

.section { padding: clamp(56px, 8vw, 104px) 0; }
.section--warm { background: var(--aifb-background-warm); }
.section--dark { background: var(--aifb-navy); color: #fff; }

.section__head { max-width: 780px; margin: 0 auto clamp(36px, 5vw, 56px); text-align: center; }
.section__title {
  font-size: clamp(1.6rem, 3.4vw, 2.4rem);
  line-height: 1.2;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--aifb-navy);
}
.section--dark .section__title { color: #fff; }
.section__lead { margin-top: 16px; font-size: 1.08rem; color: var(--aifb-text-muted); }
.section--dark .section__lead { color: rgba(255, 255, 255, 0.82); }

/* Formulaire Google Forms intégré : centré */
.form-embed { display: flex; flex-direction: column; align-items: center; }
.form-embed__frame { display: block; }
.form-embed__fallback { margin-top: 14px; text-align: center; }
.section--dark .form-embed__fallback a { color: rgba(255, 255, 255, 0.82); }
.section--dark .form-embed__fallback a:hover { color: var(--aifb-yellow-brazil); }

/* Grilles : mobile 1 col → tablette 2 → desktop 3 */
.grid { display: grid; gap: 24px; grid-template-columns: 1fr; }
@media (min-width: 640px) {
  .grid--2, .grid--3 { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 980px) {
  .grid--3 { grid-template-columns: repeat(3, 1fr); }
}

/* ---------- 4. Boutons ---------- */
.btn {
  --btn-bg: var(--aifb-navy);
  --btn-fg: #fff;
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 22px;
  background: var(--btn-bg); color: var(--btn-fg);
  border: 2px solid transparent; border-radius: 999px;
  font-weight: 600; font-size: 0.98rem; line-height: 1;
  transition: transform 0.18s var(--ease), box-shadow 0.18s var(--ease), background 0.18s, color 0.18s;
  text-align: center;
}
.btn:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.btn:active { transform: translateY(0); }

.btn--primary { --btn-bg: var(--aifb-navy); --btn-fg: #fff; }
.btn--accent  { --btn-bg: var(--aifb-yellow-brazil); --btn-fg: var(--aifb-navy); font-weight: 700; }
.btn--secondary { --btn-bg: transparent; --btn-fg: var(--aifb-green-brazil); border-color: var(--aifb-green-brazil); }
.btn--secondary:hover { --btn-bg: var(--aifb-green-brazil); --btn-fg: #fff; }
.btn--ghost { --btn-bg: transparent; --btn-fg: #fff; border-color: rgba(255, 255, 255, 0.7); }
.btn--ghost:hover { --btn-bg: rgba(255, 255, 255, 0.12); }
.btn--soft { --btn-bg: rgba(0, 85, 164, 0.08); --btn-fg: var(--aifb-blue-france); font-weight: 600; padding: 10px 16px; font-size: 0.9rem; }
.btn--soft:hover { --btn-bg: var(--aifb-blue-france); --btn-fg: #fff; }
.btn--block { display: flex; width: 100%; }
.btn--lg { padding: 16px 26px; font-size: 1.05rem; }

/* ---------- 5. Header ---------- */
.skip-link {
  position: absolute; left: 12px; top: -60px; z-index: 200;
  background: var(--aifb-navy); color: #fff; padding: 10px 16px; border-radius: 8px;
  transition: top 0.2s;
}
.skip-link:focus { top: 12px; }

.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: saturate(160%) blur(12px);
  -webkit-backdrop-filter: saturate(160%) blur(12px);
  border-bottom: 1px solid transparent;
  transition: box-shadow 0.25s, border-color 0.25s, background 0.25s;
}
.site-header.is-scrolled { box-shadow: var(--shadow-sm); border-bottom-color: var(--aifb-border); background: rgba(255, 255, 255, 0.92); }
.header__inner { display: flex; align-items: center; gap: 18px; min-height: var(--header-h); }

.brand { display: inline-flex; align-items: center; gap: 12px; }
.brand__mark { display: grid; place-items: center; }
.brand__text { display: flex; flex-direction: column; line-height: 1.05; }
.brand__name { font-weight: 800; font-size: 1.35rem; letter-spacing: 0.04em; color: var(--aifb-navy); }
.brand__name--light { color: #fff; font-size: 1.6rem; }
.brand__baseline { font-size: 0.66rem; color: var(--aifb-text-muted); letter-spacing: 0.02em; text-transform: uppercase; }

.nav { display: none; gap: 26px; margin-left: auto; }
.nav a { font-weight: 500; font-size: 0.96rem; color: var(--aifb-navy); position: relative; padding: 6px 0; }
.nav a::after {
  content: ""; position: absolute; left: 0; bottom: 0; height: 2px; width: 0;
  background: var(--aifb-gradient-accent); transition: width 0.25s var(--ease);
}
.nav a:hover::after { width: 100%; }

.header__actions { display: flex; align-items: center; gap: 14px; margin-left: auto; }
@media (min-width: 980px) { .header__actions { margin-left: 0; } }

.lang-switch { display: flex; align-items: center; gap: 4px; color: var(--aifb-text-muted); font-size: 0.86rem; }
.lang-switch__btn {
  background: none; border: none; padding: 4px 4px; font-weight: 600; color: var(--aifb-text-muted);
  border-radius: 6px; transition: color 0.15s;
}
.lang-switch__btn:hover { color: var(--aifb-navy); }
.lang-switch__btn.is-active { color: var(--aifb-blue-france); }

.header__cta { display: none; }
@media (min-width: 560px) { .header__cta { display: inline-flex; } }

/* Burger (mobile) */
.burger { display: inline-flex; flex-direction: column; gap: 5px; background: none; border: none; padding: 8px; }
.burger span { width: 24px; height: 2px; background: var(--aifb-navy); border-radius: 2px; transition: transform 0.25s, opacity 0.2s; }
.burger[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.burger[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.burger[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

@media (min-width: 980px) {
  .nav { display: flex; }
  .burger { display: none; }
}

/* Menu mobile déployé */
@media (max-width: 979px) {
  .nav {
    position: fixed; inset: var(--header-h) 0 auto 0;
    flex-direction: column; gap: 0; margin: 0;
    background: #fff; border-bottom: 1px solid var(--aifb-border);
    box-shadow: var(--shadow-md);
    padding: 8px 22px 18px;
    transform: translateY(-130%); transition: transform 0.3s var(--ease);
    visibility: hidden;
  }
  .nav.is-open { transform: translateY(0); visibility: visible; }
  .nav a { padding: 14px 0; border-bottom: 1px solid var(--aifb-border); font-size: 1.05rem; }
  .nav a::after { display: none; }
}

/* ---------- 6. Hero ---------- */
.hero { position: relative; color: #fff; background: var(--aifb-gradient-main); overflow: hidden; }
.hero::before {
  content: ""; position: absolute; inset: 0;
  background:
    radial-gradient(circle at 18% 20%, rgba(255, 255, 255, 0.08), transparent 40%),
    radial-gradient(circle at 85% 80%, rgba(255, 223, 0, 0.10), transparent 45%);
  pointer-events: none;
}
.hero__inner {
  position: relative;
  display: grid; grid-template-columns: 1fr; gap: 36px; align-items: center;
  padding: clamp(56px, 9vw, 110px) 0 clamp(52px, 8vw, 96px);
}
@media (min-width: 920px) { .hero__inner { grid-template-columns: 1.05fr 0.95fr; gap: 48px; } }

.hero__eyebrow { font-size: 0.84rem; letter-spacing: 0.12em; text-transform: uppercase; color: var(--aifb-yellow-brazil); font-weight: 600; }
.hero__title {
  margin-top: 14px;
  font-size: clamp(2.1rem, 5.2vw, 3.5rem);
  line-height: 1.08; font-weight: 800; letter-spacing: -0.025em;
}
.hl-blue { color: #9CC4FF; }
.hl-green { color: #7BE3A6; }
.hero__subtitle { margin-top: 20px; font-size: 1.18rem; font-weight: 500; color: rgba(255, 255, 255, 0.95); max-width: 40ch; }
.hero__text { margin-top: 14px; font-size: 1.02rem; color: rgba(255, 255, 255, 0.78); max-width: 52ch; }
.hero__cta { margin-top: 30px; display: flex; flex-wrap: wrap; gap: 14px; }

.hero__visual { display: flex; justify-content: center; }
.netmap { width: 100%; max-width: 480px; filter: drop-shadow(0 18px 40px rgba(0, 0, 0, 0.28)); }
.netmap__label { fill: #fff; font-family: var(--font); font-size: 15px; font-weight: 600; }
.netmap__arc { stroke-dasharray: 760; stroke-dashoffset: 760; animation: draw 2.4s var(--ease) forwards 0.3s; }
.netmap__nodes circle { animation: pulse 3s ease-in-out infinite; transform-origin: center; transform-box: fill-box; }
.netmap__nodes circle:nth-child(2) { animation-delay: 0.6s; }
.netmap__nodes circle:nth-child(3) { animation-delay: 1.2s; }
.netmap__nodes circle:nth-child(4) { animation-delay: 1.8s; }

@keyframes draw { to { stroke-dashoffset: 0; } }
@keyframes pulse { 0%, 100% { opacity: 0.5; r: 4; } 50% { opacity: 1; r: 6.5; } }

/* ---------- 7. Cartes génériques ---------- */
.card {
  background: var(--aifb-white); border: 1px solid var(--aifb-border);
  border-radius: var(--radius); padding: 28px 26px;
  box-shadow: var(--shadow-sm); position: relative;
  transition: transform 0.2s var(--ease), box-shadow 0.2s var(--ease);
  border-top: 4px solid var(--aifb-border);
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.card--accent-blue { border-top-color: var(--aifb-blue-france); }
.card--accent-green { border-top-color: var(--aifb-green-brazil); }
.card--accent-yellow { border-top-color: var(--aifb-yellow-brazil); }
.card__title { font-size: 1.2rem; font-weight: 700; color: var(--aifb-navy); margin-bottom: 8px; }
.card__text { color: var(--aifb-text-muted); font-size: 0.98rem; }

.card--icon .card__icon {
  display: inline-grid; place-items: center; width: 52px; height: 52px;
  border-radius: 14px; margin-bottom: 16px; color: #fff;
}
.card--accent-blue .card__icon { background: var(--aifb-blue-france); }
.card--accent-green .card__icon { background: var(--aifb-green-brazil); }
.card--accent-yellow .card__icon { background: var(--aifb-yellow-brazil); color: var(--aifb-navy); }

/* ---------- 8. Pour qui ---------- */
.grid--tight { gap: 18px; }
.audience {
  background: #fff; border: 1px solid var(--aifb-border); border-radius: var(--radius);
  padding: 24px; box-shadow: var(--shadow-sm); transition: border-color 0.2s, transform 0.2s var(--ease);
}
.audience:hover { transform: translateY(-3px); border-color: var(--aifb-blue-france); }
.audience__title { font-size: 1.08rem; font-weight: 700; color: var(--aifb-navy); margin-bottom: 6px; }
.audience__title::before { content: ""; display: inline-block; width: 8px; height: 8px; border-radius: 50%; background: var(--aifb-gradient-accent); margin-right: 10px; vertical-align: middle; }
.audience__text { color: var(--aifb-text-muted); font-size: 0.95rem; }

/* ---------- 9. Actions (feature) ---------- */
.feature {
  background: #fff; border: 1px solid var(--aifb-border); border-radius: var(--radius);
  padding: 30px 28px; box-shadow: var(--shadow-sm);
}
.feature__title { font-size: 1.25rem; font-weight: 700; color: var(--aifb-navy); margin-bottom: 16px; padding-bottom: 12px; border-bottom: 2px solid var(--aifb-background-warm); }
.feature__list li { position: relative; padding: 7px 0 7px 26px; color: var(--aifb-text); font-size: 0.98rem; }
.feature__list li::before {
  content: ""; position: absolute; left: 0; top: 14px; width: 9px; height: 9px;
  border-radius: 50%; background: var(--aifb-green-brazil);
}

/* ---------- 10. Clusters ---------- */
.cluster {
  background: #fff; border: 1px solid var(--aifb-border); border-radius: var(--radius);
  padding: 26px; box-shadow: var(--shadow-sm); display: flex; flex-direction: column;
  transition: transform 0.2s var(--ease), box-shadow 0.2s var(--ease);
}
.cluster:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.cluster__icon { display: block; width: 40px; height: 40px; border-radius: 6px; background: var(--aifb-green-brazil); margin-bottom: 14px; }
.cluster__title { font-size: 1.12rem; font-weight: 700; color: var(--aifb-navy); margin-bottom: 6px; }
.cluster__text { color: var(--aifb-text-muted); font-size: 0.95rem; flex: 1; margin-bottom: 18px; }
.cluster__btn { align-self: flex-start; }

/* ---------- 11. Écoles ---------- */
.schools { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; max-width: 900px; margin: 0 auto; }
.schools li {
  background: #fff; border: 1px solid var(--aifb-border); border-radius: 999px;
  padding: 10px 20px; font-weight: 500; font-size: 0.95rem; color: var(--aifb-navy);
  box-shadow: var(--shadow-sm); transition: transform 0.18s, border-color 0.18s;
}
.schools li:hover { transform: translateY(-2px); border-color: var(--aifb-blue-france); }
.schools__more { background: transparent; border-style: dashed; color: var(--aifb-text-muted); }
.schools__cta { text-align: center; margin-top: 36px; }
.schools__note { max-width: 620px; margin: 0 auto 20px; color: var(--aifb-text-muted); }

/* ---------- 12. São Paulo ---------- */
.saopaulo { display: grid; grid-template-columns: 1fr; gap: 36px; align-items: center; }
@media (min-width: 920px) { .saopaulo { grid-template-columns: 1.1fr 0.9fr; gap: 48px; } }
.saopaulo .section__lead, .saopaulo .section__title { text-align: left; margin-left: 0; }
.event-card {
  background: var(--aifb-gradient-main); color: #fff; border-radius: var(--radius);
  padding: 32px 30px; box-shadow: var(--shadow-lg);
}
.event-card__badge {
  display: inline-block; background: var(--aifb-yellow-brazil); color: var(--aifb-navy);
  font-weight: 700; font-size: 0.78rem; letter-spacing: 0.04em; text-transform: uppercase;
  padding: 6px 14px; border-radius: 999px; margin-bottom: 16px;
}
.event-card__title { font-size: 1.7rem; font-weight: 800; margin-bottom: 18px; }
.event-card__list { margin-bottom: 24px; }
.event-card__list li { padding: 8px 0 8px 28px; position: relative; color: rgba(255, 255, 255, 0.92); }
.event-card__list li::before { content: "→"; position: absolute; left: 0; color: var(--aifb-yellow-brazil); font-weight: 700; }

/* ---------- 13. Formulaire ---------- */
.form { max-width: 760px; margin: 0 auto; display: flex; flex-direction: column; gap: 22px; }
.form__group {
  border: 1px solid rgba(255, 255, 255, 0.16); border-radius: var(--radius);
  padding: 24px; background: rgba(255, 255, 255, 0.04);
}
.form__group legend { font-weight: 700; font-size: 1.05rem; color: var(--aifb-yellow-brazil); padding: 0 10px; }
.form__row { display: grid; grid-template-columns: 1fr; gap: 16px; margin-bottom: 16px; }
@media (min-width: 600px) { .form__row { grid-template-columns: 1fr 1fr; } }
.field { display: flex; flex-direction: column; gap: 6px; margin-bottom: 16px; }
.field:last-child { margin-bottom: 0; }
.field > span { font-size: 0.9rem; font-weight: 500; color: rgba(255, 255, 255, 0.88); }
.field input, .field select {
  width: 100%; padding: 12px 14px; border-radius: var(--radius-sm);
  border: 1px solid rgba(255, 255, 255, 0.22); background: rgba(255, 255, 255, 0.96);
  color: var(--aifb-text); font-size: 0.98rem; font-family: inherit;
  transition: border-color 0.15s, box-shadow 0.15s;
}
.field input:focus, .field select:focus { outline: none; border-color: var(--aifb-yellow-brazil); box-shadow: 0 0 0 3px rgba(255, 223, 0, 0.3); }
.field input:invalid:not(:placeholder-shown):not(:focus) { border-color: var(--aifb-red-france); }

.checks { display: grid; grid-template-columns: 1fr; gap: 12px; }
@media (min-width: 600px) { .checks { grid-template-columns: 1fr 1fr; } }
.check { display: flex; align-items: flex-start; gap: 10px; font-size: 0.95rem; color: rgba(255, 255, 255, 0.9); cursor: pointer; }
.check input { width: 18px; height: 18px; margin-top: 3px; accent-color: var(--aifb-green-brazil); flex-shrink: 0; }
.form__group .check { margin-bottom: 10px; }

.form__error { background: rgba(239, 65, 53, 0.16); border: 1px solid var(--aifb-red-france); color: #ffd5d1; padding: 12px 16px; border-radius: var(--radius-sm); font-size: 0.95rem; }
.form__hint { font-size: 0.85rem; color: rgba(255, 255, 255, 0.6); text-align: center; }

/* ---------- 14. Partenaires ---------- */
.partners { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; max-width: 880px; margin: 0 auto; }
.partners li {
  background: var(--aifb-background-warm); border: 1px solid var(--aifb-border);
  border-radius: var(--radius-sm); padding: 12px 20px; font-weight: 500; color: var(--aifb-navy); font-size: 0.95rem;
}
.partners__cta { text-align: center; margin-top: 36px; }

/* ---------- 15. Footer ---------- */
.site-footer { background: var(--aifb-navy); color: rgba(255, 255, 255, 0.78); padding-top: 56px; }
.footer__inner { display: grid; grid-template-columns: 1fr; gap: 36px; padding-bottom: 40px; }
@media (min-width: 720px) { .footer__inner { grid-template-columns: 2fr 1fr 1fr; } }
.footer__baseline { font-weight: 600; color: #fff; margin-top: 4px; }
.footer__desc { margin-top: 12px; font-size: 0.95rem; max-width: 42ch; }
.footer__loc { margin-top: 14px; font-size: 0.92rem; }
.footer__col h4 { color: #fff; font-size: 0.95rem; text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 14px; }
.footer__col a { display: block; padding: 6px 0; font-size: 0.96rem; transition: color 0.15s; }
.footer__col a:hover { color: var(--aifb-yellow-brazil); }
.footer__bottom { border-top: 1px solid rgba(255, 255, 255, 0.12); padding: 20px 0; font-size: 0.86rem; }
.footer__bottom .container { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px 20px; }
.footer__bottom p { color: rgba(255, 255, 255, 0.6); margin: 0; }
.footer__credit { display: inline-flex; align-items: center; gap: 10px; color: rgba(255, 255, 255, 0.6); transition: color 0.15s; }
.footer__credit:hover { color: var(--aifb-yellow-brazil); }
.footer__credit-logo { width: 30px; height: 30px; object-fit: contain; background: #fff; border-radius: 6px; padding: 3px; box-sizing: border-box; box-shadow: 0 1px 3px rgba(0, 0, 0, 0.25); }

/* Liseré drapeau subtil en bas de page */
.site-footer::after { content: ""; display: block; height: 4px; background: var(--aifb-gradient-accent); }

/* ---------- 16. Confirmation / pages simples ---------- */
.simple-page { min-height: 70vh; display: grid; place-items: center; text-align: center; padding: 80px 0; }
.simple-page__inner { max-width: 620px; }
.simple-page h1 { font-size: clamp(2rem, 5vw, 2.8rem); color: var(--aifb-navy); font-weight: 800; margin-bottom: 16px; }
.simple-page p { color: var(--aifb-text-muted); margin-bottom: 14px; }
.simple-page .btn { margin-top: 20px; }
.check-badge { width: 84px; height: 84px; border-radius: 50%; background: var(--aifb-green-brazil); display: grid; place-items: center; margin: 0 auto 24px; color: #fff; }
.prose { max-width: 760px; margin: 0 auto; }
.prose h2 { color: var(--aifb-navy); font-size: 1.3rem; margin: 28px 0 10px; }
.prose p, .prose li { color: var(--aifb-text-muted); margin-bottom: 10px; }
.prose ul { list-style: disc; padding-left: 22px; }

/* ---------- 17. Animations d'apparition ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.6s var(--ease), transform 0.6s var(--ease); }
.reveal.is-visible { opacity: 1; transform: none; }

/* ---------- 18. Accessibilité : reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
  .reveal { opacity: 1; transform: none; }
  .netmap__arc { stroke-dashoffset: 0; }
}