/* ISTEN Premium UI - palette sombre et accents violets */
:root {
  color-scheme: dark;
  --surface: #14161B;
  --surface-dim: #1A1F28;
  --surface-bright: #262A34;
  --surface-container-lowest: #11131A;
  --surface-container-low: #191F27;
  --surface-container: #212835;
  --surface-container-high: #2C3444;
  --surface-container-highest: #34415A;
  --primary: #D0BCFF;
  --on-primary: #2D1E5E;
  --primary-container: #4F378B;
  --on-primary-container: #EADDFF;
  --accent-green: #0B7A3B;
  --accent-red: #C62828;
  --accent-blue: #0A192F;
  --text: #F7F3FF;
  --muted: #B5ADC8;
  --border: rgba(208,188,255,0.16);
  --radius: 24px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: 'Montserrat', sans-serif;
  color: var(--text);
  background: radial-gradient(circle at top, rgba(208,188,255,0.14), transparent 24%),
              linear-gradient(180deg, #0F1218 0%, #141820 32%, #161C25 100%);
}
.skip-link {
  position: absolute;
  top: -40px;
  left: 6px;
  background: var(--primary);
  color: var(--on-primary);
  padding: 8px;
  text-decoration: none;
  border-radius: 4px;
  z-index: 1000;
}

.skip-link:focus {
  top: 6px;
}
body.theme-renew {
  --surface: #0F2814;
  --surface-dim: #081609;
  --surface-bright: #1A3A22;
  --surface-container-lowest: #051003;
  --surface-container: #0E2612;
  --surface-container-high: #1A3A22;
  --text: #FFFFFF;
  --muted: #B0D9B8;
  --border: rgba(11, 122, 59, 0.32);
  --primary: #DC2626;
  --on-primary: #FFFFFF;
  --primary-container: #0B7A3B;
  --accent-green: #22C55E;
  --accent-blue: #3B82F6;
  --accent-red: #FF3B3B;
  background: radial-gradient(circle at 20% 20%, rgba(220, 38, 38, 0.18), transparent 32%),
              radial-gradient(circle at 80% 80%, rgba(11, 122, 59, 0.16), transparent 36%),
              linear-gradient(180deg, #081609 0%, #0F2814 48%, #1A3A22 100%);
}

body.theme-renew .site-header {
  background: linear-gradient(90deg, rgba(15, 40, 20, 0.92), rgba(14, 38, 18, 0.92));
  border-bottom: 2px solid;
  border-image: linear-gradient(90deg, #DC2626, #0B7A3B) 1;
  backdrop-filter: blur(14px);
}

body.theme-renew .hero-section {
  background: linear-gradient(135deg, rgba(15, 40, 20, 0.88), rgba(26, 58, 34, 0.92));
  border: 2px solid;
  border-image: linear-gradient(135deg, #FF3B3B, #22C55E) 1;
  box-shadow: 0 16px 48px rgba(220, 38, 38, 0.16), 0 0 32px rgba(11, 122, 59, 0.12);
}

body.theme-renew .hero-section::before {
  background: radial-gradient(circle at 18% 20%, rgba(255, 59, 59, 0.18), transparent 32%),
              radial-gradient(circle at 76% 76%, rgba(34, 197, 94, 0.16), transparent 28%);
}

body.theme-renew .hero-section::after {
  background-image: radial-gradient(circle at 50% 12%, rgba(255, 170, 60, 0.1), transparent 38%);
}

body.theme-renew .hero-basic {
  background: linear-gradient(135deg, rgba(255, 59, 59, 0.08), rgba(34, 197, 94, 0.08));
  border: 2px solid;
  border-image: linear-gradient(135deg, #FF3B3B, #22C55E) 1;
}

body.theme-renew .stat-card,
body.theme-renew .feature-card,
body.theme-renew .faq-card,
body.theme-renew .method-card,
body.theme-renew .metric-card,
body.theme-renew .project-card,
body.theme-renew .course-card,
body.theme-renew .value-card,
body.theme-renew .career-card,
body.theme-renew .dg-card,
body.theme-renew .contact-panel,
body.theme-renew .contact-form {
  background: linear-gradient(135deg, rgba(26, 58, 34, 0.72), rgba(15, 40, 20, 0.88));
  border: 1.5px solid var(--border);
  box-shadow: 0 8px 24px rgba(220, 38, 38, 0.1), 0 4px 12px rgba(34, 197, 94, 0.08);
}

body.theme-renew .course-card:hover {
  border-color: var(--accent-green);
  background: linear-gradient(135deg, rgba(34, 197, 94, 0.16), rgba(255, 59, 59, 0.08));
  box-shadow: 0 12px 36px rgba(34, 197, 94, 0.18), 0 8px 16px rgba(220, 38, 38, 0.12);
}

body.theme-renew .btn-primary {
  background: linear-gradient(135deg, var(--primary), #FF5555);
  color: var(--on-primary);
  box-shadow: 0 4px 12px rgba(255, 59, 59, 0.24);
}

body.theme-renew .btn-primary:hover {
  background: linear-gradient(135deg, #FF5555, #FF7777);
  box-shadow: 0 8px 24px rgba(255, 59, 59, 0.32);
}

body.theme-renew .btn-secondary {
  color: var(--accent-green);
  border-color: var(--accent-green);
  background: rgba(34, 197, 94, 0.12);
}

body.theme-renew .btn-secondary:hover {
  background: rgba(34, 197, 94, 0.22);
  border-color: #4ADE80;
  box-shadow: 0 4px 12px rgba(34, 197, 94, 0.2);
}

body.theme-renew .theme-toggle {
  border-color: var(--primary);
  background: linear-gradient(135deg, rgba(220, 38, 38, 0.16), rgba(34, 197, 94, 0.16));
  color: var(--primary);
}

body.theme-renew .theme-toggle:hover {
  background: linear-gradient(135deg, rgba(220, 38, 38, 0.26), rgba(34, 197, 94, 0.22));
  border-color: var(--accent-green);
}

body.theme-renew .dg-card {
  box-shadow: 0 16px 48px rgba(220, 38, 38, 0.16), 0 8px 24px rgba(34, 197, 94, 0.12);
}

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

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

button, input, select, textarea {
  font: inherit;
}

.loader-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;
  display: grid;
  place-items: center;
  background: radial-gradient(circle at center, rgba(208,188,255,0.20), rgba(20,18,24,0.96));
  backdrop-filter: blur(12px);
  opacity: 1;
  transition: opacity 0.8s ease, visibility 0.8s ease;
}

.loader-overlay.hidden {
  opacity: 0;
  visibility: hidden;
}

.loader-content {
  position: relative;
  display: grid;
  gap: 18px;
  place-items: center;
  padding: 32px;
  border: 1px solid rgba(255,255,255,0.14);
  border-radius: 28px;
  background: rgba(12,10,18,0.72);
  box-shadow: 0 32px 120px rgba(10, 8, 28, 0.55);
  overflow: visible;
}

.loader-ring,
.loader-ring.loader-ring-secondary {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  border: 4px solid rgba(255,255,255,0.08);
  border-top-color: rgba(208,188,255,0.95);
  animation: spin 1.6s linear infinite;
}

.loader-ring-secondary {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 170px;
  height: 170px;
  border: 3px solid rgba(255,255,255,0.05);
  border-top-color: rgba(11,122,59,0.55);
  animation-duration: 2.4s;
}

.loader-content p {
  margin: 0;
  color: rgba(237,221,255,0.95);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-size: 0.9rem;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.page-shell {
  max-width: 1320px;
  margin: 0 auto;
  padding: 24px 24px 32px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 18px 0;
  backdrop-filter: blur(18px);
  background: rgba(20,18,24,0.86);
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.brand-container {
  display: flex;
  align-items: center;
}

.brand-logo {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  color: var(--text);
  font-weight: 700;
}

.brand-logo img {
  width: 44px;
  height: 44px;
  border-radius: 14px;
  object-fit: cover;
  border: 1px solid rgba(255,255,255,0.12);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
}

.site-nav a {
  color: var(--muted);
  transition: color 180ms ease;
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--primary);
}

.nav-toggle {
  display: none;
  border: none;
  background: transparent;
  width: 42px;
  height: 42px;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  padding: 6px;
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  border: 1px solid rgba(255,255,255,0.16);
  border-radius: 999px;
  background: rgba(255,255,255,0.06);
  color: var(--text);
  cursor: pointer;
  transition: transform 180ms ease, background 180ms ease, border-color 180ms ease;
}

.theme-toggle:hover {
  transform: translateY(-2px);
  background: rgba(208,188,255,0.14);
  border-color: rgba(208,188,255,0.32);
}

.nav-toggle span {
  display: block;
  width: 100%;
  height: 3px;
  margin: 5px 0;
  background: var(--text);
  border-radius: 999px;
}

.section {
  margin-top: 42px;
}

.hero-section {
  position: relative;
  overflow: hidden;
  display: grid;
  gap: 28px;
  padding: 48px;
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0.02));
  border: 1px solid rgba(208,188,255,0.16);
}

.hero-section::before {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: radial-gradient(circle at 18% 18%, rgba(138,114,208,0.14), transparent 24%),
              radial-gradient(circle at 72% 80%, rgba(11,122,59,0.14), transparent 22%);
  mix-blend-mode: screen;
  opacity: 0.82;
  animation: driftGlow 14s ease-in-out infinite alternate;
}

.hero-section::after {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: radial-gradient(circle at 50% 14%, rgba(255,255,255,0.24), transparent 36%),
                    linear-gradient(140deg, transparent 0%, rgba(39,33,27,0.06) 40%, transparent 100%);
}

.hero-section > * {
  position: relative;
  z-index: 1;
}

.hero-immersive {
  grid-template-columns: 1.5fr 1fr;
  align-items: center;
}

.hero-basic {
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(208,188,255,0.12);
}

.hero-copy h1,
.section-intro-copy h1,
.section-intro h2 {
  margin: 0;
  font-size: clamp(2.7rem, 3.6vw, 4.4rem);
  line-height: 1.02;
  letter-spacing: -0.04em;
  color: var(--text);
}

.hero-copy p,
.section-intro-copy p,
.section-copy p,
.feature-card p,
.faq-card p,
.method-card p,
.contact-block p {
  color: var(--muted);
  line-height: 1.8;
}

.eyebrow {
  display: inline-flex;
  margin-bottom: 16px;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--primary);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-top: 28px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 52px;
  padding: 0 28px;
  border-radius: 999px;
  border: 1px solid transparent;
  transition: transform 180ms ease, background-color 180ms ease, border-color 180ms ease;
  font-weight: 600;
}

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

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-container));
  color: var(--on-primary);
}

.btn-secondary {
  background: transparent;
  color: var(--text);
  border-color: rgba(255,255,255,0.16);
}

.stat-card,
.feature-card,
.faq-card,
.method-card,
.metric-card,
.project-card,
.course-card,
.value-card,
.career-card,
.dg-card,
.contact-panel,
.contact-form {
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 24px;
  padding: 28px;
}

.stat-card {
  display: grid;
  gap: 12px;
  align-items: start;
  justify-items: start;
}

.stat-card span {
  font-size: 1.6rem;
}

.stat-card strong,
.metric-card strong {
  font-size: 2rem;
  color: var(--text);
}

.stat-card.accent,
.metric-card.accent-blue,
.value-card.accent-green,
.value-card.accent-blue,
.value-card.accent-red,
.course-card.accent-blue,
.course-card.accent-green,
.project-card.accent-green,
.project-card.accent-red,
.project-card.accent-blue {
  border-color: transparent;
  background: rgba(208,188,255,0.12);
}

.course-card {
  transition: transform 260ms ease, box-shadow 260ms ease, border-color 260ms ease, background-color 260ms ease;
}

.course-card:hover {
  transform: translateY(-10px) scale(1.02);
  border-color: rgba(208,188,255,0.3);
  background: rgba(208,188,255,0.10);
  box-shadow: 0 28px 80px rgba(16, 12, 35, 0.28);
}

.course-card:hover h2 {
  color: var(--primary);
}

.section-keypoints .grid,
.section-values .grid,
.section-methodology .grid,
.section-careers .grid,
.section-faq .grid,
.section-projects .grid {
  display: grid;
  gap: 22px;
}

.grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.grid-5 {
  grid-template-columns: repeat(5, minmax(0, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.section-intro,
.section-intro-copy {
  max-width: 720px;
}

.checklist {
  list-style: none;
  padding: 0;
  margin: 24px 0 0;
  display: grid;
  gap: 14px;
}

.checklist li {
  position: relative;
  padding-left: 28px;
}

.checklist li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--primary);
}

.quick-stats {
  display: grid;
  gap: 18px;
}

.metric-card {
  text-align: left;
}

.metric-card p {
  margin: 10px 0 0;
}

.section-intro-full {
  display: grid;
  gap: 30px;
  justify-items: center;
  text-align: center;
  max-width: 920px;
  margin: 0 auto;
}

.section-intro-full .section-intro-copy {
  max-width: 760px;
}

.dg-card {
  display: grid;
  gap: 22px;
  align-items: center;
  justify-items: center;
  text-align: center;
  width: 100%;
  max-width: 420px;
  padding: 36px 26px;
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.10);
  box-shadow: 0 24px 80px rgba(0,0,0,0.18);
}

.dg-card img {
  width: 220px;
  height: 220px;
  object-fit: cover;
  border-radius: 50%;
  border: 1px solid rgba(255,255,255,0.12);
  box-shadow: 0 24px 64px rgba(0,0,0,0.30);
}

.dg-card strong {
  display: block;
  font-size: 1.2rem;
}

.section-faq {
  padding-bottom: 12px;
}

.faq-card h3,
.method-card h3,
.career-card h3,
.project-card h2,
.course-card h2,
.value-card h3 {
  margin-top: 0;
}

.section-contact-grid {
  display: grid;
  gap: 24px;
  grid-template-columns: 1.2fr 1fr;
}

.contact-panel {
  display: grid;
  gap: 20px;
}

.contact-block {
  padding: 24px;
}

.contact-block h2 {
  margin-bottom: 16px;
}

.contact-form {
  display: grid;
  gap: 18px;
}

.contact-form label {
  display: grid;
  gap: 10px;
  color: var(--muted);
}

.contact-form input,
.contact-form select,
.contact-form textarea {
  width: 100%;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.10);
  border-radius: 16px;
  color: var(--text);
  padding: 16px;
}

.contact-form input:focus,
.contact-form select:focus,
.contact-form textarea:focus {
  outline: 2px solid rgba(208,188,255,0.24);
}

.site-footer {
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid rgba(255,255,255,0.06);
  display: grid;
  gap: 24px;
}

.footer-brand {
  display: grid;
  gap: 16px;
}

.footer-brand img {
  width: 42px;
  height: 42px;
  border-radius: 14px;
}

.footer-links {
  display: grid;
  gap: 18px;
}

.footer-links h3 {
  margin-bottom: 8px;
}

.hero-copy,
.hero-panel,
.section-intro-copy,
.dg-card,
.feature-card,
.faq-card,
.method-card,
.project-card,
.course-card,
.value-card,
.career-card,
.metric-card {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.9s ease, transform 0.9s ease;
}

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

@keyframes driftGlow {
  from {
    transform: translate(0, 0) scale(1);
  }
  to {
    transform: translate(40px, -22px) scale(1.05);
  }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(28px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 1024px) {
  .hero-immersive,
  .section-intro-full,
  .section-contact-grid,
  .grid-4,
  .grid-5,
  .grid-3 {
    grid-template-columns: 1fr;
  }

  .site-header {
    align-items: flex-start;
  }

  .site-nav {
    display: none;
    flex-direction: column;
    width: 100%;
    background: rgba(20,18,24,0.92);
    position: absolute;
    top: 80px;
    left: 0;
    padding: 16px 24px 24px;
    border-radius: 0 0 24px 24px;
  }

  .site-nav.open {
    display: flex;
  }

  .nav-toggle {
    display: flex;
    flex-direction: column;
  }
}

@media (max-width: 680px) {
  .page-shell {
    padding: 20px 18px 24px;
  }

  .hero-section {
    padding: 32px;
  }

  .btn {
    width: 100%;
  }
}

/* Footer Styles */
.site-footer {
  margin-top: 48px;
  padding: 48px 0 24px;
  border-top: 1px solid rgba(255,255,255,0.08);
  display: grid;
  gap: 32px;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
}

.footer-brand {
  display: grid;
  gap: 16px;
}

.footer-brand img {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  object-fit: cover;
  border: 1px solid rgba(255,255,255,0.12);
}

.footer-brand h3 {
  margin: 0;
  font-size: 1.4rem;
  font-weight: 700;
}

.footer-brand p {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.footer-links {
  display: grid;
  gap: 16px;
}

.footer-links h3 {
  margin: 0 0 12px;
  font-size: 1.1rem;
  font-weight: 600;
}

.footer-links p {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.footer-links ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 8px;
}

.footer-links li a {
  color: var(--muted);
  text-decoration: none;
  transition: color 180ms ease;
}

.footer-links li a:hover {
  color: var(--primary);
}

.footer-copyright {
  grid-column: 1 / -1;
  margin-top: 24px;
  padding-top: 24px;
  border-top: 1px solid rgba(255,255,255,0.06);
  text-align: center;
}

.footer-copyright p {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
}

/* Theme-specific footer styles */
body.theme-renew .site-footer {
  border-top-color: rgba(220, 38, 38, 0.14);
}

body.theme-renew .footer-brand img {
  border-color: rgba(220, 38, 38, 0.18);
}

body.theme-renew .footer-links li a:hover {
  color: var(--accent-green);
}

body.theme-renew .footer-copyright {
  border-top-color: rgba(220, 38, 38, 0.08);
}

/* Responsive footer */
@media (max-width: 1024px) {
  .site-footer {
    grid-template-columns: 1fr 1fr;
    gap: 40px;
  }

  .footer-brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 680px) {
  .site-footer {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 32px 0 16px;
  }

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

  .footer-links {
    text-align: center;
  }
}