:root{
  --bg:#0b1020;--bg-2:#0f1730;--text:#e8ecf3;--muted:#a8b0c2;--primary:#5bd0ff;--accent:#7cffb7;--warning:#ffce6b;--danger:#ff7b7b
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{
  font-family:'Inter',system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;
  color:var(--text);background:linear-gradient(180deg,var(--bg),var(--bg-2));
  min-height:100vh;display:flex;flex-direction:column;
  opacity:0;transform:translateY(6px);transition:opacity .6s ease, transform .6s ease
}
.is-loaded body{opacity:1;transform:none}
.container{max-width:1120px;margin:0 auto;padding:0 20px}
.skip-link{position:absolute;left:-9999px;top:auto;width:1px;height:1px;overflow:hidden}
.skip-link:focus{left:16px;top:16px;width:auto;height:auto;background:#000;color:#fff;padding:8px 12px;border-radius:6px}

.site-header{position:sticky;top:0;z-index:50;background:rgba(10,14,28,.6);backdrop-filter:blur(8px);border-bottom:1px solid rgba(255,255,255,.06)}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:64px}
.brand{display:flex;align-items:center;color:var(--text);text-decoration:none;gap:12px}
.brand-logo{width:40px;height:40px;border-radius:8px;object-fit:cover;filter:drop-shadow(0 6px 18px rgba(0,0,0,.35))}
.brand-name{font-weight:800;letter-spacing:.2px}

.nav-toggle{display:none;position:relative;width:40px;height:40px;border:0;background:transparent;color:var(--text);cursor:pointer}
.nav-toggle span{position:absolute;left:8px;right:8px;height:2px;background:var(--text);border-radius:2px;transition:transform .25s ease,opacity .2s}
.nav-toggle span:nth-child(1){top:12px}
.nav-toggle span:nth-child(2){top:19px}
.nav-toggle span:nth-child(3){top:26px}

.site-nav ul{display:flex;gap:20px;list-style:none;margin:0;padding:0}
.site-nav a{color:var(--muted);text-decoration:none;padding:10px 8px;border-radius:8px;transition:color .2s,background .2s}
.site-nav a:hover,.site-nav a:focus{color:var(--text);background:rgba(255,255,255,.06)}

@media (max-width:900px){
  .nav-toggle{display:inline-block}
  .site-nav{position:absolute;inset:64px 0 auto 0;background:rgba(10,14,28,.95);border-bottom:1px solid rgba(255,255,255,.08);transform-origin:top;transform:scaleY(0);transition:transform .25s ease}
  .site-nav[aria-hidden="false"]{transform:scaleY(1)}
  .site-nav ul{flex-direction:column;padding:16px}
}

/* Révélations au scroll accessibles */
.reveal{opacity:0;transform:translateY(16px);transition:opacity .7s ease, transform .7s ease;transition-delay:var(--stagger,0ms)}
.reveal.is-visible{opacity:1;transform:none}

/* Réduction d'animations si l'utilisateur préfère moins de mouvement */
@media (prefers-reduced-motion: reduce){
  *{animation-duration:.01ms !important;animation-iteration-count:1 !important;transition-duration:.01ms !important;scroll-behavior:auto !important}
  body{opacity:1 !important;transform:none !important}
  .reveal{opacity:1 !important;transform:none !important}
}

/* Animation de transition entre pages */
.page-transition{position:fixed;inset:0;z-index:9999;background:var(--primary);transform:scale(0);border-radius:50%;pointer-events:none;animation:pageTransition 1.2s cubic-bezier(.2,.8,.2,1) forwards}
@keyframes pageTransition{
 0%{transform:scale(0)}
 50%{transform:scale(1.5)}
 100%{transform:scale(0);opacity:0}
}

/* Paillettes bleutées qui tournoient */
.sparkles{position:relative;height:120px;overflow:hidden;margin:16px 0}
.sparkle{position:absolute;width:4px;height:4px;background:var(--primary);border-radius:50%;animation:sparkleFloat 3s linear infinite}
.sparkle:nth-child(1){left:10%;animation-delay:0s;animation-duration:4s}
.sparkle:nth-child(2){left:20%;animation-delay:0.5s;animation-duration:3.5s}
.sparkle:nth-child(3){left:30%;animation-delay:1s;animation-duration:4.5s}
.sparkle:nth-child(4){left:40%;animation-delay:1.5s;animation-duration:3s}
.sparkle:nth-child(5){left:50%;animation-delay:2s;animation-duration:4.2s}
.sparkle:nth-child(6){left:60%;animation-delay:2.5s;animation-duration:3.8s}
.sparkle:nth-child(7){left:70%;animation-delay:3s;animation-duration:4.1s}
.sparkle:nth-child(8){left:80%;animation-delay:0.8s;animation-duration:3.3s}
.sparkle:nth-child(9){left:90%;animation-delay:1.2s;animation-duration:4.3s}
@keyframes sparkleFloat{
 0%{transform:translateY(120px) rotate(0deg);opacity:0}
 20%{opacity:1}
 80%{opacity:1}
 100%{transform:translateY(-20px) rotate(360deg);opacity:0}
}

/* Animation du menu qui se retourne */
.site-nav a{transition:all .3s cubic-bezier(.2,.8,.2,1);transform-style:preserve-3d}
.site-nav a:hover{transform:rotateY(180deg);color:var(--primary)}

.hero{position:relative;padding:80px 0}
.hero-inner{display:grid;grid-template-columns:1.2fr 1fr;align-items:center;gap:32px}
.slogan{font-size:clamp(28px,4vw,48px);line-height:1.05;margin:0 0 12px;perspective:1000px}
.slogan span{display:block;font-weight:800}
.slogan-front{transform:translateZ(24px);text-shadow:0 6px 20px rgba(91,208,255,.3);color:var(--primary)}
.slogan-back{transform:translateZ(-6px) rotateX(6deg);opacity:.9;color:var(--accent)}
.tagline{color:var(--muted);margin:8px 0 20px}
.hero-ctas{display:flex;gap:12px;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;justify-content:center;padding:12px 16px;border-radius:10px;text-decoration:none;font-weight:600}
.btn-primary{background:linear-gradient(135deg,var(--primary),#3aa6ff);color:#001018;box-shadow:0 8px 22px rgba(58,166,255,.35)}
.btn-ghost{border:1px solid rgba(255,255,255,.18);color:var(--text);background:transparent}

.hero-visual{display:grid;place-items:center}
.cube{position:relative;width:160px;height:160px;transform-style:preserve-3d;animation:spin 10s linear infinite}
.cube .face{position:absolute;inset:0;display:grid;place-items:center;font-weight:800;font-size:0;color:transparent;background-image:url('../../AlphaConcept_Logo.jpg');background-size:cover;background-position:center;border:1px solid rgba(255,255,255,.2)}
.cube .face.back{transform:translateZ(-80px) rotateY(180deg)}
.cube .face.front{transform:translateZ(80px)}
.cube .face.left{transform:rotateY(-90deg) translateZ(80px)}
.cube .face.right{transform:rotateY(90deg) translateZ(80px)}
.cube .face.top{transform:rotateX(90deg) translateZ(80px)}
.cube .face.bottom{transform:rotateX(-90deg) translateZ(80px)}
@keyframes spin{to{transform:rotateX(360deg) rotateY(360deg)}}

.features{padding:40px 0 88px}
.features h2{margin:24px 0 16px}
.cards-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.card{background:rgba(255,255,255,.04);border:1px solid rgba(255,255,255,.08);border-radius:14px;padding:20px}
.card h3{margin:0 0 6px}
.card p{margin:0 0 12px;color:var(--muted)}
.card-link{color:var(--primary);text-decoration:none;font-weight:600}

.tilt3d{transform-style:preserve-3d;transition:transform .2s ease, box-shadow .2s ease}
.tilt3d:hover{transform:rotateX(6deg) rotateY(-6deg) translateY(-2px);box-shadow:0 20px 40px rgba(0,0,0,.35)}

@media (max-width:900px){
  .hero-inner{grid-template-columns:1fr}
  .cards-grid{grid-template-columns:1fr}
}

.site-footer{margin-top:auto;border-top:1px solid rgba(255,255,255,.08);background:rgba(10,14,28,.5)}
.footer-inner{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px;padding:20px 0}
.footer-nav{display:flex;gap:16px}
.footer-nav a{color:var(--muted);text-decoration:none}
.footer-nav a:hover{color:var(--text)}

/* Bloc vidéo générique */
.video{position:relative;aspect-ratio:16/9;background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.08);border-radius:12px;overflow:hidden}
.video iframe,.video video{position:absolute;inset:0;width:100%;height:100%}