/* ============================================================
   youfanglin 极简响应式全站样式表 (2026最新版)
   特点：无JS依赖、无图片依赖、极致加载速度
   ============================================================ */

/* 1. 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fcfcfc;
    padding-bottom: 50px;
}

/* 2. 容器布局 */
.wrapper {
    max-width: 1000px;
    margin: 0 auto;
    background: #fff;
    box-shadow: 0 0 10px rgba(0,0,0,0.05);
    min-height: 100vh;
}

/* 3. 头部 - 用纯代码模拟Logo视觉 */
header {
    padding: 30px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 2px solid #0056b3;
}

.logo-text {
    font-size: 30px;
    font-weight: 800;
    color: #0056b3;
    text-transform: uppercase;
    letter-spacing: -1px;
}

.header-contact {
    font-size: 14px;
    color: #666;
    text-align: right;
}

/* 4. 导航栏 - 纯CSS驱动，无JS */
nav {
    display: flex;
    background: #333;
    position: sticky;
    top: 0;
    z-index: 100;
}

nav a {
    color: #fff;
    text-decoration: none;
    padding: 15px 25px;
    font-size: 15px;
    transition: background 0.3s;
    flex: 1;
    text-align: center;
}

nav a:hover {
    background: #444;
}

nav a.active {
    background: #0056b3;
    font-weight: bold;
}

/* 5. 核心内容区样式 */
main {
    padding: 30px 20px;
}

.section-title {
    margin-bottom: 30px;
    border-left: 6px solid #0056b3;
    padding-left: 15px;
}

.section-title h1, .section-title h2 {
    font-size: 24px;
    color: #222;
}

/* 6. 首页专用 Banner (纯代码渐变替代图片) */
.hero-banner {
    background: linear-gradient(135deg, #0056b3 0%, #002d5d 100%);
    color: white;
    padding: 80px 20px;
    text-align: center;
    margin-bottom: 30px;
}

.hero-banner h2 { font-size: 36px; margin-bottom: 10px; }
.hero-banner p { font-size: 18px; opacity: 0.9; }

/* 7. 产品网格布局 */
.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 25px;
}

.product-card {
    border: 1px solid #eee;
    padding: 20px;
    text-align: center;
    text-decoration: none;
    color: #333;
    transition: 0.3s;
}

.product-card:hover {
    border-color: #0056b3;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

/* 占位图框 (替代原本的产品图) */
.no-img-placeholder {
    width: 100%;
    height: 180px;
    background: #f0f0f0;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #bbb;
    font-size: 12px;
    margin-bottom: 15px;
    border: 1px dashed #ddd;
}

/* 8. 列表页分页样式 */
.pagination {
    margin-top: 40px;
    text-align: center;
    padding: 20px;
    border-top: 1px solid #eee;
}

.pagination a, .pagination span {
    display: inline-block;
    padding: 8px 16px;
    margin: 0 5px;
    border: 1px solid #ddd;
    text-decoration: none;
    color: #666;
    border-radius: 4px;
}

.pagination .active {
    background: #0056b3;
    color: #fff;
    border-color: #0056b3;
}

/* 9. 页脚 */
footer {
    padding: 40px 20px;
    background: #f8f9fa;
    border-top: 1px solid #eee;
    text-align: center;
    color: #999;
    font-size: 13px;
}

/* 10. 响应式适配 (手机端) */
@media (max-width: 650px) {
    header {
        flex-direction: column;
        text-align: center;
    }
    
    .logo-text { margin-bottom: 10px; }

    nav {
        flex-wrap: wrap;
    }
    
    nav a {
        flex: 1 0 50%; /* 导航在手机上变为两列 */
        border-bottom: 1px solid #444;
        padding: 12px 5px;
        font-size: 14px;
    }
    
    .hero-banner { padding: 40px 10px; }
    .hero-banner h2 { font-size: 24px; }
}