/* ==========================================================
   EDUSPHÈRE — Feuille de styles
   Design : éditorial, refined, lisible, mobile-first
   Police : Quicksand
   Couleurs : Bleu marine #003366, Vert émeraude #009B77, Jaune moutarde #E1AD01
   ========================================================== */

/* ====== VARIABLES ====== */
:root {
  /* Couleurs principales */
  --bleu: #003366;
  --bleu-clair: #1a4d80;
  --bleu-foncé: #00264d;
  --emerald: #009B77;
  --emerald-clair: #00b890;
  --moutarde: #E1AD01;
  --moutarde-clair: #f0c44a;

  /* Neutres */
  --blanc: #ffffff;
  --creme: #faf7f0;
  --creme-2: #f3ede0;
  --gris-clair: #e6e6e6;
  --gris-moyen: #8a8a8a;
  --gris-foncé: #2c2c2c;
  --noir: #1a1a1a;

  /* Typographie */
  --font-base: 'Quicksand', sans-serif;

  /* Espacements */
  --container-max: 1180px;
  --container-padding: 1.5rem;
  --section-padding-y: 6rem;
  --section-padding-y-mobile: 4rem;

  /* Radius */
  --r-sm: 8px;
  --r-md: 16px;
  --r-lg: 24px;

  /* Ombre */
  --shadow-sm: 0 2px 8px rgba(0, 51, 102, 0.06);
  --shadow-md: 0 8px 24px rgba(0, 51, 102, 0.1);
  --shadow-lg: 0 16px 48px rgba(0, 51, 102, 0.15);

  /* Transitions */
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ====== RESET & BASE ====== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-base);
  font-weight: 400;
  font-size: 17px;
  line-height: 1.65;
  color: var(--gris-foncé);
  background-color: var(--blanc);
  overflow-x: hidden;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--transition);
}

ul {
  list-style: none;
}

button {
  background: none;
  border: none;
  cursor: pointer;
  font-family: inherit;
}

::selection {
  background: var(--emerald);
  color: var(--blanc);
}

/* ====== CONTAINER ====== */
.container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
  width: 100%;
}

/* ====== TYPOGRAPHIE GLOBALE ====== */
h1, h2, h3, h4 {
  font-family: var(--font-base);
  color: var(--bleu);
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.section-eyebrow {
  font-size: 0.875rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--emerald);
  margin-bottom: 1rem;
}

.eyebrow-light {
  color: var(--moutarde);
}

.eyebrow-yellow {
  color: var(--moutarde);
}

.section-title {
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  font-weight: 700;
  margin-bottom: 1.5rem;
  max-width: 800px;
}

.lead {
  font-size: clamp(1.05rem, 1.6vw, 1.2rem);
  font-weight: 400;
  color: var(--gris-foncé);
  max-width: 720px;
  margin-bottom: 1.25rem;
  line-height: 1.7;
}

.lead-light {
  color: rgba(255, 255, 255, 0.85);
}

.text-emerald {
  color: var(--emerald);
}

.text-white {
  color: var(--blanc);
}

/* ====== BOUTONS ====== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 1.6rem;
  font-family: var(--font-base);
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0.01em;
  border-radius: 999px;
  transition: all var(--transition);
  cursor: pointer;
  white-space: nowrap;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.btn-primary {
  background-color: var(--bleu);
  color: var(--blanc);
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  background-color: var(--emerald);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-ghost {
  background-color: transparent;
  color: var(--bleu);
  border: 1.5px solid var(--bleu);
}

.btn-ghost:hover {
  background-color: var(--bleu);
  color: var(--blanc);
  transform: translateY(-2px);
}

.btn-yellow {
  background-color: var(--moutarde);
  color: var(--bleu);
  box-shadow: var(--shadow-sm);
}

.btn-yellow:hover {
  background-color: var(--moutarde-clair);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-large {
  padding: 1.05rem 2rem;
  font-size: 1rem;
}

.btn-nav {
  padding: 0.65rem 1.3rem;
  font-size: 0.9rem;
}

/* ====== HEADER ====== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background-color: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(0, 51, 102, 0.06);
  transition: padding var(--transition), box-shadow var(--transition);
}

.site-header.scrolled {
  box-shadow: var(--shadow-sm);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 1rem;
  padding-bottom: 1rem;
  gap: 2rem;
}

.logo-link {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.logo-img {
  height: 48px;
  width: auto;
  transition: transform var(--transition);
}

.logo-link:hover .logo-img {
  transform: scale(1.04);
}

.main-nav {
  flex: 1;
  display: flex;
  justify-content: center;
}

.nav-list {
  display: flex;
  gap: 2.25rem;
}

.nav-list a {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--bleu);
  position: relative;
  padding: 0.5rem 0;
}

.nav-list a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 2px;
  background-color: var(--emerald);
  transition: width var(--transition);
}

.nav-list a:hover {
  color: var(--emerald);
}

.nav-list a:hover::after {
  width: 100%;
}

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 0.5rem;
}

.menu-toggle span {
  display: block;
  width: 26px;
  height: 2px;
  background-color: var(--bleu);
  border-radius: 2px;
  transition: all var(--transition);
}

.menu-toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.menu-toggle.open span:nth-child(2) {
  opacity: 0;
}

.menu-toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.mobile-nav {
  display: none;
  background-color: var(--blanc);
  border-top: 1px solid var(--gris-clair);
}

.mobile-nav.open {
  display: block;
}

.mobile-nav ul {
  padding: 1.5rem var(--container-padding);
}

.mobile-nav li {
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--gris-clair);
}

.mobile-nav li:last-child {
  border-bottom: none;
  padding-top: 1.25rem;
}

.mobile-nav a {
  color: var(--bleu);
  font-weight: 500;
  font-size: 1rem;
  display: block;
}

.mobile-cta {
  background-color: var(--bleu);
  color: var(--blanc) !important;
  padding: 0.85rem 1.25rem;
  border-radius: 999px;
  text-align: center;
  font-weight: 600;
}

/* ====== HERO ====== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 100px;
  padding-bottom: 4rem;
  background: linear-gradient(135deg, #faf7f0 0%, #ffffff 60%);
  overflow: hidden;
}

.hero-decor {
  position: absolute;
  inset: 0;
  pointer-events: none;
  overflow: hidden;
}

.circle {
  position: absolute;
  border-radius: 50%;
  opacity: 0.08;
}

.circle-1 {
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--bleu) 0%, transparent 70%);
  top: -200px;
  right: -150px;
}

.circle-2 {
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, var(--emerald) 0%, transparent 70%);
  bottom: -200px;
  left: -100px;
}

.circle-3 {
  width: 300px;
  height: 300px;
  background: radial-gradient(circle, var(--moutarde) 0%, transparent 70%);
  top: 50%;
  right: 20%;
  opacity: 0.05;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 900px;
}

.hero-eyebrow {
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--emerald);
  margin-bottom: 1.5rem;
  opacity: 0;
  animation: fadeUp 0.8s 0.1s ease forwards;
}

.hero-title {
  font-size: clamp(2.5rem, 6.5vw, 5rem);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.03em;
  color: var(--bleu);
  margin-bottom: 1.75rem;
  opacity: 0;
  animation: fadeUp 0.8s 0.25s ease forwards;
}

.hero-subtitle {
  font-size: clamp(1.1rem, 1.8vw, 1.3rem);
  line-height: 1.6;
  color: var(--gris-foncé);
  max-width: 640px;
  margin-bottom: 2.5rem;
  opacity: 0;
  animation: fadeUp 0.8s 0.4s ease forwards;
}

.hero-ctas {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  opacity: 0;
  animation: fadeUp 0.8s 0.55s ease forwards;
}

@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ====== BAND TRANSITION ====== */
.band {
  background-color: var(--creme);
  padding: 4rem 0;
  border-top: 1px solid var(--creme-2);
  border-bottom: 1px solid var(--creme-2);
}

.band-quote {
  font-size: clamp(1.15rem, 2.2vw, 1.55rem);
  line-height: 1.5;
  text-align: center;
  font-weight: 400;
  color: var(--bleu);
  max-width: 900px;
  margin: 0 auto;
  font-style: italic;
}

.band-emphasis {
  font-style: normal;
  font-weight: 600;
  color: var(--emerald);
}

/* ====== SECTIONS ====== */
.section {
  padding: var(--section-padding-y) 0;
}

.section-dark {
  background: linear-gradient(160deg, var(--bleu) 0%, var(--bleu-foncé) 100%);
  color: var(--blanc);
  position: relative;
  overflow: hidden;
}

.section-dark::before {
  content: '';
  position: absolute;
  top: -200px;
  right: -200px;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, var(--emerald) 0%, transparent 70%);
  opacity: 0.15;
  border-radius: 50%;
  pointer-events: none;
}

.section-dark .section-title {
  color: var(--blanc);
}

/* ====== À PROPOS ====== */
.about-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 4rem;
  align-items: start;
}

.about-text p {
  margin-bottom: 1rem;
  color: var(--gris-foncé);
  font-size: 1.05rem;
  line-height: 1.75;
}

.about-text strong {
  color: var(--bleu);
  font-weight: 600;
}

.about-credentials {
  background-color: var(--creme);
  padding: 2.5rem 2rem;
  border-radius: var(--r-md);
  border-left: 4px solid var(--emerald);
  position: sticky;
  top: 110px;
}

.about-credentials ul {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.about-credentials li {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.cred-number {
  font-size: 3rem;
  font-weight: 700;
  color: var(--emerald);
  line-height: 1;
  letter-spacing: -0.03em;
  flex-shrink: 0;
  min-width: 60px;
}

.cred-label {
  font-size: 0.95rem;
  color: var(--bleu);
  font-weight: 500;
  line-height: 1.4;
}

/* ====== PILLARS (Approche) ====== */
.pillars {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-top: 3.5rem;
}

.pillar {
  background-color: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--r-md);
  padding: 2rem;
  transition: all var(--transition);
}

.pillar:hover {
  background-color: rgba(255, 255, 255, 0.07);
  transform: translateY(-4px);
  border-color: rgba(0, 184, 144, 0.3);
}

.pillar-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 64px;
  height: 64px;
  border-radius: var(--r-sm);
  background-color: rgba(0, 184, 144, 0.15);
  color: var(--emerald-clair);
  margin-bottom: 1.5rem;
}

.pillar h3 {
  color: var(--blanc);
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
}

.pillar p {
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.98rem;
  line-height: 1.65;
}

/* ====== ACCOMPAGNEMENTS ====== */
.accompagnements {
  background-color: var(--creme);
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-top: 3rem;
}

.topic-card {
  background-color: var(--blanc);
  border-radius: var(--r-md);
  padding: 2.5rem 2rem;
  position: relative;
  border: 1px solid var(--creme-2);
  transition: all var(--transition);
  overflow: hidden;
}

.topic-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--emerald) 0%, var(--bleu) 100%);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.5s var(--transition);
}

.topic-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: transparent;
}

.topic-card:hover::before {
  transform: scaleX(1);
}

.topic-num {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--moutarde);
  margin-bottom: 1rem;
}

.topic-card h3 {
  font-size: 1.4rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--bleu);
}

.topic-card p {
  color: var(--gris-foncé);
  font-size: 0.98rem;
  line-height: 1.7;
}

/* ====== RESSOURCES ====== */
.ressources {
  background-color: var(--blanc);
}

.social-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
  margin-top: 3rem;
}

.social-card {
  background-color: var(--creme);
  border-radius: var(--r-md);
  padding: 2rem;
  border: 1px solid var(--creme-2);
  transition: all var(--transition);
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.social-card:hover {
  background-color: var(--blanc);
  border-color: var(--emerald);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.social-icon {
  color: var(--bleu);
  transition: color var(--transition);
}

.social-card:hover .social-icon {
  color: var(--emerald);
}

.social-card h3 {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--bleu);
}

.social-card p {
  font-size: 0.9rem;
  color: var(--gris-foncé);
  line-height: 1.5;
}

.social-arrow {
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  color: var(--emerald);
  font-size: 1.25rem;
  font-weight: 700;
  opacity: 0;
  transform: translateX(-8px);
  transition: all var(--transition);
}

.social-card:hover .social-arrow {
  opacity: 1;
  transform: translateX(0);
}

.featured-video {
  margin-top: 4.5rem;
  background: linear-gradient(135deg, var(--creme) 0%, var(--creme-2) 100%);
  padding: 3rem;
  border-radius: var(--r-lg);
  border: 1px solid var(--creme-2);
  position: relative;
  overflow: hidden;
}

.featured-video::before {
  content: '';
  position: absolute;
  top: -100px;
  right: -100px;
  width: 300px;
  height: 300px;
  background: radial-gradient(circle, var(--emerald) 0%, transparent 70%);
  opacity: 0.08;
  border-radius: 50%;
  pointer-events: none;
}

.video-eyebrow {
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--moutarde);
  margin-bottom: 0.85rem;
  position: relative;
}

.featured-video h3 {
  font-size: clamp(1.35rem, 2.5vw, 1.75rem);
  font-weight: 600;
  color: var(--bleu);
  margin-bottom: 0.85rem;
  max-width: 720px;
  line-height: 1.3;
  position: relative;
}

.video-description {
  color: var(--gris-foncé);
  font-size: 1rem;
  line-height: 1.65;
  max-width: 680px;
  margin-bottom: 2rem;
  position: relative;
}

.video-wrapper {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
  border-radius: var(--r-md);
  box-shadow: var(--shadow-lg);
}

.video-wrapper iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

/* ====== CTA FINAL ====== */
.cta-final {
  background: linear-gradient(135deg, var(--bleu) 0%, var(--bleu-foncé) 100%);
  padding: var(--section-padding-y) 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-final::before {
  content: '';
  position: absolute;
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, var(--emerald) 0%, transparent 70%);
  opacity: 0.1;
  border-radius: 50%;
  top: -300px;
  right: -200px;
}

.cta-final::after {
  content: '';
  position: absolute;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--moutarde) 0%, transparent 70%);
  opacity: 0.08;
  border-radius: 50%;
  bottom: -200px;
  left: -100px;
}

.cta-inner {
  position: relative;
  z-index: 2;
  max-width: 720px;
}

.cta-title {
  font-size: clamp(2rem, 4.5vw, 3rem);
  font-weight: 700;
  color: var(--blanc);
  margin-bottom: 1.5rem;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.cta-text {
  font-size: 1.15rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.88);
  margin-bottom: 2.5rem;
}

/* ====== FOOTER ====== */
.site-footer {
  background-color: var(--bleu-foncé);
  color: rgba(255, 255, 255, 0.8);
  padding: 4rem 0 2rem;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1.5fr 1fr auto;
  gap: 3rem;
  align-items: start;
  padding-bottom: 2.5rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.footer-logo {
  height: 56px;
  width: auto;
  filter: brightness(0) invert(1);
  opacity: 0.95;
}

.footer-tagline {
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.6);
  font-style: italic;
}

.footer-nav ul {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-nav a {
  font-size: 0.95rem;
  color: rgba(255, 255, 255, 0.75);
}

.footer-nav a:hover {
  color: var(--moutarde);
}

.footer-social {
  display: flex;
  gap: 0.85rem;
}

.footer-social a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: rgba(255, 255, 255, 0.08);
  color: var(--blanc);
  transition: all var(--transition);
}

.footer-social a:hover {
  background-color: var(--emerald);
  transform: translateY(-2px);
}

.footer-bottom {
  padding-top: 2rem;
  text-align: center;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.5);
}

/* ====== ANIMATIONS AU SCROLL ====== */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ====== RESPONSIVE ====== */
@media (max-width: 992px) {
  .main-nav,
  .btn-nav {
    display: none;
  }
  .menu-toggle {
    display: flex;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .about-credentials {
    position: static;
  }

  .pillars,
  .topic-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 720px) {
  :root {
    --section-padding-y: var(--section-padding-y-mobile);
  }

  .header-inner {
    padding-top: 0.85rem;
    padding-bottom: 0.85rem;
  }

  .logo-img {
    height: 42px;
  }

  .hero {
    min-height: auto;
    padding-top: 120px;
    padding-bottom: 5rem;
  }

  .hero-ctas {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-ctas .btn {
    justify-content: center;
  }

  .pillars,
  .topic-grid {
    grid-template-columns: 1fr;
  }

  .about-credentials li {
    flex-direction: row;
    align-items: center;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 2rem;
    text-align: center;
  }

  .footer-brand {
    align-items: center;
  }

  .footer-nav ul {
    align-items: center;
  }

  .footer-social {
    justify-content: center;
  }

  .band {
    padding: 3rem 0;
  }

  .featured-video {
    padding: 1.75rem;
    margin-top: 3rem;
  }
}

/* ====== ACCESSIBILITÉ ====== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

:focus-visible {
  outline: 3px solid var(--emerald);
  outline-offset: 3px;
  border-radius: 4px;
}