* {margin:0;padding:0;box-sizing:border-box;font-family:"Microsoft Yahei";}
body{background:#f5f7fa;color:#222;line-height:1.7;}
.container{max-width:1200px;margin:0 auto;padding:0 20px;}
header{background:#165DFF;color:#fff;padding:18px 0;}
.header-wrap{display:flex;justify-content:space-between;align-items:center;}
.logo{font-size:24px;font-weight:bold;}
nav a{color:#fff;text-decoration:none;margin-left:26px;}
.banner{background:linear-gradient(135deg,#165DFF,#3684ff);color:#fff;padding:90px 0;text-align:center;}
.banner h1{font-size:40px;margin-bottom:15px;}
.section{padding:70px 0;}
.section-title{text-align:center;font-size:28px;color:#165DFF;margin-bottom:40px;}
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:28px;}
.item{background:#fff;padding:30px;border-radius:10px;box-shadow:0 2px 10px rgba(0,0,0,0.06);}
footer{background:#192438;color:#b0c4de;text-align:center;padding:35px 0;margin-top:30px;}