body{margin:0;font-family:"Microsoft YaHei",Arial;color:#333;line-height:1.8}
header{background:#111;color:white;padding:20px 8%;display:flex;justify-content:space-between}
.logo{font-size:22px;font-weight:bold}
nav a{color:white;margin:0 10px;text-decoration:none}
.hero{height:550px;background:#555;color:white;display:flex;align-items:center;padding-left:10%}
.hero h1{font-size:42px}
.btn{background:white;color:#111;padding:12px 30px;text-decoration:none}
section{padding:60px 10%}
h2{text-align:center}
.grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.card{background:#f5f5f5;padding:30px}
footer{background:#111;color:white;padding:30px;text-align:center}
@media(max-width:700px){.grid{grid-template-columns:1fr}.hero h1{font-size:30px}}