:root {
  --color-navy: #0a1f3d;
  --color-navy-2: #12335c;
  --color-blue: #5fb8e8;
  --color-blue-soft: #eaf6fc;
  --color-green: #39b27f;
  --color-green-soft: #e7f7ef;
  --color-yellow-soft: #fff5d8;
  --color-white: #ffffff;
  --color-ink: #152033;
  --color-muted: #5f6f86;
  --color-line: #d9e4ef;
  --shadow-soft: 0 24px 60px rgba(10, 31, 61, 0.16);
  --radius: 8px;
  --container: 1160px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--color-ink);
  background: var(--color-white);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.6;
  text-rendering: optimizeLegibility;
}

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

a {
  color: inherit;
  text-decoration: none;
}

button,
input,
textarea {
  font: inherit;
}

:focus-visible {
  outline: 3px solid rgba(57, 178, 127, 0.85);
  outline-offset: 3px;
}

.container {
  width: min(calc(100% - 40px), var(--container));
  margin-inline: auto;
}

.skip-link {
  position: fixed;
  left: 16px;
  top: 12px;
  z-index: 100;
  transform: translateY(-160%);
  border-radius: var(--radius);
  background: var(--color-white);
  color: var(--color-navy);
  padding: 10px 14px;
  box-shadow: var(--shadow-soft);
}

.skip-link:focus {
  transform: translateY(0);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
}

/* En-tête sticky, volontairement compact pour garder le contenu prioritaire. */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid rgba(217, 228, 239, 0.75);
  backdrop-filter: blur(16px);
}

.nav {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--color-navy);
  min-width: 0;
}

.brand__mark {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  border-radius: var(--radius);
  background: var(--color-navy);
  color: var(--color-white);
  font-weight: 800;
  letter-spacing: 0;
}

.brand strong,
.brand small {
  display: block;
}

.brand strong {
  font-size: 0.98rem;
  line-height: 1.1;
}

.brand small {
  margin-top: 2px;
  color: var(--color-muted);
  font-size: 0.78rem;
  letter-spacing: 0;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav__links a {
  border-radius: var(--radius);
  color: #263b56;
  font-size: 0.94rem;
  font-weight: 650;
  padding: 10px 12px;
}

.nav__links a:hover {
  background: var(--color-blue-soft);
  color: var(--color-navy);
}

.nav__links .nav__contact {
  margin-left: 4px;
  background: var(--color-navy);
  color: var(--color-white);
}

.nav__links .nav__contact:hover {
  background: var(--color-navy-2);
  color: var(--color-white);
}

.nav__toggle {
  display: none;
  width: 44px;
  height: 44px;
  place-items: center;
  border: 1px solid var(--color-line);
  border-radius: var(--radius);
  background: var(--color-white);
  color: var(--color-navy);
  cursor: pointer;
}

.nav__toggle-line,
.nav__toggle-line::before,
.nav__toggle-line::after {
  width: 20px;
  height: 2px;
  display: block;
  border-radius: 999px;
  background: currentColor;
  transition:
    transform 180ms ease,
    opacity 180ms ease;
}

.nav__toggle-line {
  position: relative;
}

.nav__toggle-line::before,
.nav__toggle-line::after {
  content: "";
  position: absolute;
  left: 0;
}

.nav__toggle-line::before {
  top: -7px;
}

.nav__toggle-line::after {
  top: 7px;
}

.nav--open .nav__toggle-line {
  background: transparent;
}

.nav--open .nav__toggle-line::before {
  transform: translateY(7px) rotate(45deg);
}

.nav--open .nav__toggle-line::after {
  transform: translateY(-7px) rotate(-45deg);
}

.hero {
  position: relative;
  isolation: isolate;
  min-height: 560px;
  display: grid;
  align-items: center;
  overflow: hidden;
  background: var(--color-navy);
}

.hero__picture {
  position: absolute;
  inset: 0;
  z-index: -2;
}

.hero__image {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.hero__overlay {
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    linear-gradient(90deg, rgba(10, 31, 61, 0.96) 0%, rgba(10, 31, 61, 0.82) 36%, rgba(10, 31, 61, 0.24) 74%),
    linear-gradient(0deg, rgba(10, 31, 61, 0.18), rgba(10, 31, 61, 0.02));
}

.hero__content {
  padding-block: clamp(68px, 8vw, 86px) clamp(46px, 5vw, 56px);
  color: var(--color-white);
}

.hero__content > * {
  max-width: 680px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--color-green);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.hero h1,
.section h2 {
  margin: 0;
  color: inherit;
  line-height: 1.05;
  letter-spacing: 0;
}

.hero h1 {
  max-width: 760px;
  font-size: clamp(2.55rem, 6vw, 4.45rem);
}

.hero__lead {
  margin: 24px 0 0;
  color: rgba(255, 255, 255, 0.9);
  font-size: clamp(1.08rem, 2vw, 1.38rem);
  line-height: 1.55;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.button {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  padding: 12px 18px;
  font-weight: 800;
  line-height: 1.2;
  text-align: center;
  cursor: pointer;
  transition:
    transform 180ms ease,
    border-color 180ms ease,
    background 180ms ease,
    color 180ms ease,
    box-shadow 180ms ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button--primary {
  background: var(--color-green);
  color: #062516;
  box-shadow: 0 14px 32px rgba(57, 178, 127, 0.28);
}

.button--primary:hover {
  background: #4bc890;
}

.button--secondary {
  border-color: rgba(255, 255, 255, 0.45);
  background: rgba(255, 255, 255, 0.12);
  color: var(--color-white);
  backdrop-filter: blur(8px);
}

.button--secondary:hover {
  background: rgba(255, 255, 255, 0.22);
}

.button--full {
  width: 100%;
}

.section {
  padding-block: clamp(72px, 9vw, 112px);
}

.section--intro {
  background: var(--color-white);
  padding-top: clamp(56px, 6vw, 76px);
}

.section--soft {
  background: linear-gradient(180deg, var(--color-white), var(--color-blue-soft));
}

.section--seo {
  background: #f7fbfe;
}

.section--blue {
  background: var(--color-navy);
  color: var(--color-white);
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
  gap: clamp(34px, 6vw, 86px);
  align-items: start;
}

.split--reverse {
  grid-template-columns: minmax(280px, 0.84fr) minmax(0, 1.16fr);
  align-items: center;
}

.section__heading h2,
.section__body h2,
.launch h2,
.contact-copy h2 {
  font-size: clamp(2rem, 4vw, 3.35rem);
}

.section__heading--center {
  max-width: 720px;
  margin: 0 auto 42px;
  text-align: center;
}

.section__body {
  color: var(--color-muted);
  font-size: 1.08rem;
}

.section__body p {
  margin: 0;
}

.section__body p + p {
  margin-top: 18px;
}

.section__body--light {
  color: rgba(255, 255, 255, 0.82);
}

.section__body--light h2 {
  margin-bottom: 22px;
  color: var(--color-white);
}

.mission-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.mission-card {
  position: relative;
  min-height: 238px;
  border: 1px solid var(--color-line);
  border-radius: var(--radius);
  background: var(--color-white);
  padding: 26px;
  overflow: hidden;
  box-shadow: 0 12px 32px rgba(10, 31, 61, 0.06);
}

.mission-card::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 5px;
  background: var(--color-blue);
}

.mission-card:nth-child(2n)::before {
  background: var(--color-green);
}

.mission-card:nth-child(3n)::before {
  background: #f2c84b;
}

.mission-card__icon {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  margin-bottom: 28px;
  border-radius: var(--radius);
  background: var(--color-blue-soft);
  color: var(--color-navy);
  font-size: 0.8rem;
  font-weight: 900;
}

.mission-card:nth-child(2n) .mission-card__icon {
  background: var(--color-green-soft);
}

.mission-card:nth-child(3n) .mission-card__icon {
  background: var(--color-yellow-soft);
}

.mission-card h3 {
  margin: 0 0 12px;
  color: var(--color-navy);
  font-size: 1.14rem;
  line-height: 1.25;
}

.mission-card p {
  margin: 0;
  color: var(--color-muted);
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.topic-card {
  border: 1px solid var(--color-line);
  border-radius: var(--radius);
  background: var(--color-white);
  padding: 24px;
  box-shadow: 0 12px 32px rgba(10, 31, 61, 0.06);
}

.topic-card h3 {
  margin: 0 0 10px;
  color: var(--color-navy);
  font-size: 1.08rem;
  line-height: 1.25;
}

.topic-card p {
  margin: 0;
  color: var(--color-muted);
}

.school-panel {
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius);
  background:
    linear-gradient(145deg, rgba(95, 184, 232, 0.2), rgba(57, 178, 127, 0.13)),
    rgba(255, 255, 255, 0.08);
  padding: clamp(26px, 4vw, 42px);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.18);
}

.school-panel p,
.school-panel span {
  margin: 0;
  color: rgba(255, 255, 255, 0.76);
}

.school-panel strong {
  display: block;
  margin: 18px 0;
  color: var(--color-white);
  font-size: clamp(2rem, 5vw, 4rem);
  line-height: 1;
  letter-spacing: 0;
}

.launch {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 0.72fr);
  gap: clamp(28px, 5vw, 70px);
  align-items: stretch;
}

.launch__date,
.launch__cta {
  border-radius: var(--radius);
  padding: clamp(28px, 5vw, 48px);
}

.launch__date {
  min-height: 320px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  background: var(--color-blue-soft);
}

.launch__date h2 {
  color: var(--color-navy);
  max-width: 720px;
}

.launch__cta {
  display: flex;
  flex-direction: column;
  justify-content: center;
  background: var(--color-navy);
  color: var(--color-white);
}

.launch__cta h3 {
  margin: 0 0 12px;
  font-size: 1.45rem;
}

.launch__cta p {
  margin: 0 0 26px;
  color: rgba(255, 255, 255, 0.82);
}

.section--faq {
  background: var(--color-white);
}

.faq-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.82fr) minmax(0, 1.18fr);
  gap: clamp(34px, 6vw, 86px);
  align-items: start;
}

.faq-list {
  display: grid;
  gap: 12px;
}

.faq-item {
  border: 1px solid var(--color-line);
  border-radius: var(--radius);
  background: var(--color-white);
  box-shadow: 0 10px 28px rgba(10, 31, 61, 0.05);
}

.faq-item summary {
  cursor: pointer;
  color: var(--color-navy);
  font-weight: 850;
  line-height: 1.35;
  padding: 20px 22px;
}

.faq-item p {
  margin: 0;
  color: var(--color-muted);
  padding: 0 22px 22px;
}

.section--contact {
  background: #f7fbfe;
}

.contact-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(340px, 0.78fr);
  gap: clamp(32px, 6vw, 82px);
  align-items: start;
}

.contact-copy p {
  max-width: 620px;
  color: var(--color-muted);
  font-size: 1.08rem;
}

.contact-details {
  display: grid;
  gap: 8px;
  margin-top: 20px;
}

.contact-link {
  display: inline-flex;
  width: fit-content;
  color: var(--color-navy);
  font-size: clamp(1.08rem, 2vw, 1.28rem);
  font-weight: 850;
}

.contact-link:hover {
  color: var(--color-green);
}

.status-note {
  margin-top: 24px;
  padding-left: 16px;
  border-left: 4px solid var(--color-green);
}

.contact-form {
  border: 1px solid var(--color-line);
  border-radius: var(--radius);
  background: var(--color-white);
  padding: clamp(22px, 4vw, 32px);
  box-shadow: var(--shadow-soft);
}

.field + .field {
  margin-top: 18px;
}

.field label {
  display: block;
  margin-bottom: 8px;
  color: var(--color-navy);
  font-size: 0.92rem;
  font-weight: 780;
}

.field input,
.field textarea {
  width: 100%;
  border: 1px solid #cbd8e6;
  border-radius: var(--radius);
  background: var(--color-white);
  color: var(--color-ink);
  padding: 13px 14px;
  transition:
    border-color 180ms ease,
    box-shadow 180ms ease;
}

.field textarea {
  resize: vertical;
}

.field input::placeholder,
.field textarea::placeholder {
  color: #7f8ea2;
}

.field input:focus,
.field textarea:focus {
  border-color: var(--color-blue);
  box-shadow: 0 0 0 4px rgba(95, 184, 232, 0.2);
  outline: 0;
}

.contact-form .button {
  margin-top: 22px;
}

.form-feedback {
  min-height: 24px;
  margin: 14px 0 0;
  color: var(--color-muted);
  font-size: 0.94rem;
}

.footer {
  background: #07182f;
  color: var(--color-white);
  padding-block: 28px;
}

.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.footer p {
  margin: 2px 0 0;
  color: rgba(255, 255, 255, 0.72);
}

/* Animation progressive activée uniquement si JavaScript est disponible. */
body.has-js .reveal {
  transform: translateY(18px);
  opacity: 0;
  transition:
    transform 680ms ease,
    opacity 680ms ease;
}

body.has-js .reveal.is-visible {
  transform: translateY(0);
  opacity: 1;
}

@media (max-width: 980px) {
  .hero {
    min-height: 560px;
  }

  .hero__overlay {
    background:
      linear-gradient(90deg, rgba(10, 31, 61, 0.94) 0%, rgba(10, 31, 61, 0.72) 55%, rgba(10, 31, 61, 0.28) 100%),
      linear-gradient(0deg, rgba(10, 31, 61, 0.24), rgba(10, 31, 61, 0.1));
  }

  .split,
  .split--reverse,
  .launch,
  .contact-layout {
    grid-template-columns: 1fr;
  }

  .mission-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (max-width: 760px) {
  .container {
    width: min(calc(100% - 32px), var(--container));
  }

  .nav {
    min-height: 64px;
  }

  body.has-js .nav__toggle {
    display: grid;
  }

  body.has-js .nav__links {
    position: absolute;
    left: 16px;
    right: 16px;
    top: calc(100% + 10px);
    display: grid;
    gap: 4px;
    padding: 10px;
    border: 1px solid var(--color-line);
    border-radius: var(--radius);
    background: var(--color-white);
    box-shadow: var(--shadow-soft);
    transform: translateY(-8px);
    opacity: 0;
    pointer-events: none;
    transition:
      transform 180ms ease,
      opacity 180ms ease;
  }

  body.has-js .nav--open .nav__links {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .nav__links {
    flex-wrap: wrap;
    justify-content: flex-end;
  }

  .nav__links a {
    width: 100%;
    padding: 12px;
  }

  .nav__links .nav__contact {
    margin-left: 0;
  }

  .hero {
    min-height: 520px;
  }

  .hero__image {
    object-position: center bottom;
  }

  .hero__overlay {
    background:
      linear-gradient(180deg, rgba(10, 31, 61, 0.9) 0%, rgba(10, 31, 61, 0.76) 54%, rgba(10, 31, 61, 0.18) 100%),
      linear-gradient(90deg, rgba(10, 31, 61, 0.84) 0%, rgba(10, 31, 61, 0.58) 58%, rgba(10, 31, 61, 0.06) 100%);
  }

  .hero__content {
    padding-block: 64px 88px;
  }

  .hero__content > * {
    max-width: 94%;
  }

  .hero__lead {
    margin-top: 18px;
  }

  .hero__actions {
    margin-top: 26px;
  }

  .button {
    width: 100%;
  }

  .section {
    padding-block: 64px;
  }

  .section__heading--center {
    margin-bottom: 30px;
    text-align: left;
  }

  .mission-grid {
    grid-template-columns: 1fr;
  }

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

  .mission-card {
    min-height: auto;
  }

  .school-panel strong {
    font-size: clamp(2.1rem, 15vw, 3.4rem);
  }

  .launch__date {
    min-height: 240px;
  }

  .contact-layout {
    gap: 28px;
  }

  .footer__inner {
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (max-width: 440px) {
  .brand strong {
    max-width: 150px;
    white-space: normal;
  }

  .hero {
    min-height: 500px;
  }

  .hero h1 {
    font-size: clamp(2.05rem, 10.5vw, 2.75rem);
  }

  .hero__lead {
    font-size: 1rem;
  }

  .contact-form {
    padding: 18px;
  }
}

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

  body.has-js .reveal {
    transform: none;
    opacity: 1;
  }
}