/* 基础重置 */
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: "Helvetica Neue", Arial, sans-serif; line-height: 1.6; }

/* 容器 */
.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
}

/* 顶部导航 */
header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}
header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}
.logo {
    font-size: 24px;
    font-weight: bold;
    color: #2c3e50;
}
nav a {
    margin-left: 25px;
    text-decoration: none;
    color: #34495e;
    font-weight: 500;
}

/* 主内容区 */
main {
    margin-top: 80px; /* 避开固定导航 */
}

/* 英雄区域 */
.hero {
    height: 80vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    background: linear-gradient(135deg, #6a11cb 0%, #2575fc 100%);
    color: white;
}
.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 20px;
}
.hero p {
    font-size: 1.5rem;
    opacity: 0.9;
}

/* 功能卡片 */
.features {
    padding: 80px 0;
    background: #f8f9fa;
}
.features {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 30px;
}
.card {
    background: white;
    padding: 40px 30px;
    width: 300px;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    text-align: center;
}
.card i {
    font-size: 3rem;
    color: #3498db;
    margin-bottom: 20px;
}
.card h3 {
    margin: 15px 0;
    color: #2c3e50;
}

/* 页脚 */
footer {
    background: #2c3e50;
    color: white;
    text-align: center;
    padding: 20px 0;
}
footer a {
    color: #3498db;
    text-decoration: none;
}

/* 响应式 */
@media (max-width: 768px) {
    .hero h1 { font-size: 2.5rem; }
    .hero p { font-size: 1.2rem; }
    .card { width: 100%; max-width: 300px; }
}