*{box-sizing:border-box}body{margin:0;font-family:Arial,sans-serif;line-height:1.6;color:#222}
.container{width:min(1100px,92%);margin:auto}
header{background:#0f172a;color:#fff;padding:15px 0;position:sticky;top:0}
header .container{display:flex;justify-content:space-between;align-items:center}
nav a{color:#fff;text-decoration:none;margin-left:18px}
.hero{background:linear-gradient(135deg,#2563eb,#0f172a);color:#fff;padding:90px 0;text-align:center}
.btn{display:inline-block;background:#fff;color:#2563eb;padding:12px 22px;border-radius:8px;text-decoration:none;margin:8px;font-weight:bold}
.btn.secondary{background:#111827;color:#fff}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:20px}
.card{border:1px solid #ddd;border-radius:12px;padding:20px;box-shadow:0 3px 8px rgba(0,0,0,.08)}
.dark{background:#111827;color:#fff;padding:40px 0;margin:50px 0}
footer{background:#0f172a;color:#fff;text-align:center;padding:20px 0}
@media(max-width:700px){
header .container{flex-direction:column}
nav{margin-top:10px}
nav a{display:inline-block;margin:8px}
.hero{padding:60px 0}
}