/* 头部 */
header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 60px;
    padding: 0 20px;
    background: #fff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    position: relative;
    z-index: 999;
}

/* 布局容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航组 */
.nav-group {
    display: flex;
    align-items: center;
}

.nav {
    display: flex;
    align-items: center;
}

.nav a {
    margin: 0 12px;
    font-size: 15px;
}

/* 区块 */
.section {
    padding: 40px 0;
}