*{margin:0;padding:0;box-sizing:border-box}
body{font-family:Arial,sans-serif;background:#f8fafc;color:#1f2937;line-height:1.6}
.navbar{position:sticky;top:0;background:#fff;padding:18px 8%;display:flex;justify-content:space-between;align-items:center;box-shadow:0 4px 20px rgba(0,0,0,.08)}
.logo{font-size:28px;font-weight:700}.logo span{color:#2563eb}
nav a{text-decoration:none;margin:0 12px;color:#333}
.btn{display:inline-block;background:#2563eb;color:#fff;padding:12px 22px;border-radius:8px;text-decoration:none}
.secondary{background:#fff;color:#2563eb;border:2px solid #2563eb}
.hero{padding:120px 8%;background:linear-gradient(135deg,#2563eb,#0f172a);color:#fff;text-align:center}
.hero h1{font-size:54px;margin-bottom:20px}
.hero p{max-width:700px;margin:auto auto 30px}
.section{padding:90px 8%}
.alt{background:#fff}
.section h2{text-align:center;font-size:40px;color:#2563eb;margin-bottom:50px}
.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:25px}
.card{background:#fff;padding:28px;border-radius:16px;box-shadow:0 8px 24px rgba(0,0,0,.08);transition:.3s}
.card:hover{transform:translateY(-8px)}
.book{display:grid;grid-template-columns:320px 1fr;gap:40px;align-items:center}
.cover{height:420px;background:#dbeafe;border-radius:16px;display:flex;align-items:center;justify-content:center;font-size:28px;font-weight:bold}
.badge{background:#f59e0b;padding:6px 14px;border-radius:20px}
.price{margin:20px 0;font-size:30px}.price strong{color:#16a34a}
.center{text-align:center;max-width:900px;margin:auto}
footer{background:#111827;color:#fff;text-align:center;padding:40px}
@media(max-width:768px){
.navbar{flex-direction:column;gap:10px}
.book{grid-template-columns:1fr}
.hero h1{font-size:38px}
}