/* =============================
   通用样式
   ============================= */
*{margin:0;padding:0;box-sizing:border-box;}
body{font-family:'Helvetica Neue',Arial,Helvetica,sans-serif;background:#f5f5f5;color:#333;}
a{color:#00a5e0;text-decoration:none;}
a:hover{color:#0089b9;}
img{max-width:100%;}
.container{max-width:1200px;margin:auto;padding:15px;}
.btn{display:inline-block;background:#00a5e0;color:#fff;padding:12px 30px;border-radius:4px;font-weight:600;transition:background .3s;}
.btn:hover{background:#0089b9;}
h1,h2,h3{color:#222;margin-bottom:0.6em;}
p{line-height:1.6;margin-bottom:1em;}

/* =============================
   头部
   ============================= */
.site-header{background:#fff;box-shadow:0 2px 5px rgba(0,0,0,.1);padding:15px 0;}
.site-header .logo img{height:40px;}
.main-nav{display:flex;gap:15px;margin-left:auto;}
.main-nav a{font-weight:600;}
@media (max-width:768px){
    .main-nav{flex-direction:column;align-items:flex-start;}
}

/* =============================
   主体
   ============================= */
.site-main{padding:40px 0;}
/* Hero Banner */
.hero{position:relative;background:url('assets/banner.jpg') center/cover no-repeat;height:500px;}
.hero::after{content:"";position:absolute;top:0;left:0;width:100%;height:100%;background:rgba(0,0,0,.4);}
.hero .content{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);color:#fff;text-align:center;max-width:80%;}
.hero .content h1{font-size:48px;margin-bottom:15px;}
.hero .content p{font-size:20px;margin-bottom:25px;}
.hero .content .btn{font-size:18px;}

/* Feature Cards */
.features{background:#fff;padding:60px 0;}
.feature-list{display:flex;gap:20px;flex-wrap:wrap;}
.feature-item{flex:1 1 calc(33.333% - 20px);background:#fafafa;padding:30px;border-radius:8px;box-shadow:0 2px 8px rgba(0,0,0,.05);text-align:center;}
.feature-item i{font-size:48px;color:#00a5e0;margin-bottom:15px;}
.feature-item h3{margin-bottom:10px;font-size:20px;}

/* Download Section */
.download{background:#f0f8ff;padding:60px 0;text-align:center;}
.download .btn{margin:10px 5px;}

/* FAQ */
.faq{background:#fff;padding:60px 0;}
.faq dl{max-width:800px;margin:auto;}
.faq dt{font-weight:600;margin-top:20px;}
.faq dd{margin-left:0;}

/* Contact Form */
.contact form{max-width:600px;margin:auto;display:flex;flex-direction:column;gap:15px;}
.contact input,.contact textarea{width:100%;padding:12px;border:1px solid #ddd;border-radius:4px;}
.contact button{align-self:flex-start;}

/* Footer */
.site-footer{background:#222;color:#ccc;padding:20px 0;}
.footer-top{display:flex;flex-wrap:wrap;gap:10px;font-size:0.9em;}
.footer-social a{font-size:20px;margin:0 5px;color:#ccc;}
.footer-social a:hover{color:#00a5e0;}

/* =============================
   响应式
   ============================= */
@media (max-width:992px){
    .feature-item{flex:1 1 calc(50% - 20px);}
}
@media (max-width:600px){
    .feature-item{flex:1 1 100%;}
    .hero .content h1{font-size:32px;}
}