* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: "PingFang SC","Helvetica Neue",Arial,sans-serif; color: #333; line-height: 1.6; }
.wrap { width: 90%; max-width: 1100px; margin: auto; }
.top { background: #fff; box-shadow: 0 2px 4px rgba(0,0,0,.05); padding: 10px 0; }
.top .wrap { display: flex; align-items: center; justify-content: space-between; }
nav a { margin-left: 20px; color: #0366d6; text-decoration: none; }
.banner { background: #0366d6; color: #fff; text-align: center; padding: 80px 0; }
.banner h1 { font-size: 36px; margin-bottom: 10px; }
.grid { display: flex; gap: 20px; margin-top: 20px; }
.grid > div { flex: 1; background: #f7f9fc; padding: 20px; border-radius: 6px; }
.case-list { display: flex; gap: 15px; flex-wrap: wrap; margin-top: 20px; }
.case-list img { width: 100%; border-radius: 4px; }
.footer { background: #f7f9fc; text-align: center; padding: 20px 0; margin-top: 40px; font-size: 14px; color: #666; }
@media(max-width:768px){
    nav a { margin-left: 10px; font-size: 14px; }
    .grid,.case-list{ flex-direction: column; }
}