:root{
    --primary:#005ce6;
    --text:#000;
    --bg:#fff;
}
*{margin:0;padding:0;box-sizing:border-box;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif;color:var(--text);}
body{background:var(--bg);line-height:1.6;}
.container{max-width:1100px;margin:0 auto;padding:0 20px;}
a{color:var(--primary);}
ul{list-style:none;}
img{max-width:100%;display:block;}

.header-flex{display:flex;align-items:center;justify-content:space-between;padding:10px 20px;border-bottom:1px solid #ddd;}
.logo{font-size:22px;font-weight:600;}
nav ul{display:flex;gap:20px;flex-wrap:wrap;}

.hero{text-align:center;padding:120px 20px;background:url('../img/banner.jpg') center/cover;color:#000;}
.hero h2{font-size:38px;margin-bottom:15px;}
.btn{background:var(--primary);color:#fff;padding:12px 30px;border-radius:4px;display:inline-block;margin-top:15px;}

.features{padding:80px 0;background:#fff;}
.grid-3{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:40px;}
.page-banner{background:#f2f6ff;padding:70px 20px;text-align:center;}
.page-banner h2{font-size:32px;}

.profile{max-width:1100px;margin:0 auto;padding:60px 20px;}
.profile ul,.profile ol{list-style:disc;padding-left:40px;margin:0 0 1em 0;}
.profile h4,.profile p{margin-left:0;margin-right:0;}
.avatar{width:200px;border-radius:50%;margin:20px auto;display:block;}

footer{background:#111;color:#fff;text-align:center;padding:20px 0;margin-top:60px;}

/* 新增：所有页面通用样式 */
*{margin:0;padding:0;box-sizing:border-box;font-family:'Arial',sans-serif;}
body{background-color:#f8f9fa;color:#333;line-height:1.6;}
.container{max-width:1200px;margin:0 auto;padding:0 20px;}
header{background-color:#fff;box-shadow:0 2px 10px rgba(0,0,0,0.1);position:sticky;top:0;z-index:100;}
.header-flex{display:flex;justify-content:space-between;align-items:center;padding:15px 0;}
.logo{font-size:24px;font-weight:bold;color:#2c3e50;text-decoration:none;}
nav ul{display:flex;list-style:none;}
nav ul li{margin-left:25px;}
nav ul li a{text-decoration:none;color:#34495e;font-weight:500;transition:color 0.3s;}
nav ul li a:hover{color:#3498db;}
#langBtn{background-color:#3498db;color:white;border:none;padding:8px 15px;border-radius:4px;cursor:pointer;font-weight:bold;transition:background-color 0.3s;}
#langBtn:hover{background-color:#2980b9;}
.page-banner{background:#f2f6ff;padding:70px 20px;text-align:center;margin-bottom:40px;}
.page-banner h2{font-size:36px;font-weight:700;color:#2c3e50;}
footer{background-color:#2c3e50;color:white;text-align:center;padding:30px 0;margin-top:60px;}

/* 首页特有样式 */
.hero{background:linear-gradient(rgba(255,255,255,0.9),rgba(255,255,255,0.9)),url('https://images.unsplash.com/photo-1532094349884-543bc11b234d?ixlib=rb-1.2.1&auto=format&fit=crop&w=1350&q=80') center/cover no-repeat;text-align:center;padding:100px 20px;margin-bottom:60px;color:#2c3e50;}
.hero h2{font-size:42px;margin-bottom:20px;font-weight:700;}
.hero p{font-size:22px;margin-bottom:30px;max-width:700px;margin-left:auto;margin-right:auto;color:#34495e;}
.btn{display:inline-block;background-color:#3498db;color:white;padding:12px 30px;border-radius:4px;text-decoration:none;font-weight:bold;transition:background-color 0.3s;}
.btn:hover{background-color:#2980b9;}
.features{margin:60px 0;display:flex;justify-content:center;}
.grid-3{display:grid;grid-template-columns:repeat(3,350px);gap:30px;justify-content:center;}
.feature-card{border-radius:10px;overflow:hidden;box-shadow:0 5px 15px rgba(0,0,0,0.1);transition:transform 0.3s;height:350px;display:flex;flex-direction:column;position:relative;}
.feature-card:hover{transform:translateY(-10px);}
.feature-img{height:100%;background-size:cover;background-position:center;position:relative;}
.feature-img::after{content:'';position:absolute;top:0;left:0;width:100%;height:100%;background-color:rgba(0,0,0,0.4);}
.feature-content{position:absolute;bottom:0;left:0;width:100%;padding:25px;color:white;z-index:2;background:linear-gradient(transparent,rgba(0,0,0,0.7));text-align:center;}
.feature-card h3{font-size:24px;margin-bottom:15px;font-weight:600;}
.digital-health .feature-img{background-image:url('img/index/background1.jpg');}
.epidermal-electronics .feature-img{background-image:url('img/index/background2.jpg');}
.bio-sensing .feature-img{background-image:url('img/index/background3.jpg');}

@media (max-width:1100px){.grid-3{grid-template-columns:repeat(2,350px);}}
@media (max-width:768px){.grid-3{grid-template-columns:1fr;max-width:350px;}nav ul{flex-wrap:wrap;justify-content:center;}nav ul li{margin:5px 10px;}.hero{padding:70px 20px;}.hero h2{font-size:32px;}.hero p{font-size:18px;}}
@media (max-width:600px){.header-flex{flex-direction:column;text-align:center;}.logo{margin:15px 0;}#langBtn{margin-top:15px;}.hero h2{font-size:28px;}.hero p{font-size:16px;}}