:root{
  --bg:#0b0f14;
  --text:#e7eef9;
  --muted:#a9b6c7;
  --border:rgba(255,255,255,.10);
  --shadow: 0 14px 40px rgba(0,0,0,.45);
  --radius:16px;
  --max:1100px;

  /* 0 = logo noir, 1 = logo blanc (via invert) */
  --logo-invert: 0;
}

*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  font-family: system-ui,-apple-system,Segoe UI,Roboto,Arial,sans-serif;
  background:
    radial-gradient(1000px 500px at 30% -10%, rgba(255,255,255,.08), transparent 55%),
    radial-gradient(900px 500px at 85% 0%, rgba(120,170,255,.10), transparent 60%),
    var(--bg);
  color:var(--text);
}

a{color:inherit; text-decoration:none}
a:hover{opacity:.95}

.container{max-width:var(--max); margin:0 auto; padding:22px}

.topbar{
  position:sticky; top:0; z-index:10;
  backdrop-filter: blur(10px);
  background: rgba(11,15,20,.75);
  border-bottom: 1px solid var(--border);
}

.topbar-inner{
  display:flex; align-items:center; justify-content:space-between;
  gap:14px;
  max-width:var(--max); margin:0 auto; padding:14px 22px;
}

.brand{display:flex; align-items:center; gap:12px}

/* Logo dynamique : recolor via invert() */
.logo-dynamic{
  width:auto;
  display:block;
  filter: invert(var(--logo-invert));
  transition: filter 1s linear;
}

/* tailles */
.brand .logo-dynamic{height:26px}
.hero-logo{max-width:260px; width:100%; height:auto; margin-bottom:15px}

.nav{display:flex; gap:10px; flex-wrap:wrap}
.nav a{
  padding:10px 12px;
  border:1px solid transparent;
  border-radius:12px;
  color:var(--muted);
}
.nav a:hover{border-color:var(--border); color:var(--text); background:rgba(255,255,255,.04)}
.nav a.active{border-color:var(--border); color:var(--text); background:rgba(255,255,255,.06)}

.hero{
  margin-top:22px;
  padding:28px;
  border:1px solid var(--border);
  border-radius:var(--radius);
  background: linear-gradient(180deg, rgba(255,255,255,.06), rgba(255,255,255,.02));
  box-shadow:var(--shadow);
}
.hero h1{margin:0 0 8px 0; font-size: clamp(24px, 4vw, 40px)}
.hero p{margin:0; color:var(--muted); line-height:1.5}

.grid{
  display:grid;
  grid-template-columns: repeat(3, minmax(0,1fr));
  gap:14px;
  margin-top:14px;
}
.card{
  padding:18px;
  border:1px solid var(--border);
  border-radius:var(--radius);
  background: rgba(255,255,255,.03);
}
.card h3{margin:0 0 6px 0}
.card p{margin:0; color:var(--muted); line-height:1.45}

.cta-row{display:flex; gap:10px; flex-wrap:wrap; margin-top:14px}
.btn{
  display:inline-flex; align-items:center; justify-content:center;
  padding:10px 14px;
  border-radius:14px;
  border:1px solid var(--border);
  background: rgba(255,255,255,.06);
  color:var(--text);
}
.btn:hover{background: rgba(255,255,255,.09)}
.btn.secondary{background: transparent}

.footer{
  margin:26px 0 10px 0;
  color:var(--muted);
  border-top:1px solid var(--border);
  padding-top:14px;
  font-size:14px;
}

@media (max-width: 860px){
  .grid{grid-template-columns:1fr}
  .topbar-inner{padding:12px 16px}
  .container{padding:16px}
  .brand .logo-dynamic{height:22px}
}