/* 基础设置 */
:root {
    --fs-blue: #0059b3;
    --fs-dark-blue: #00448a;
    --fs-gray-bg: #f4f7f9;
    --fs-border: #e1e8ed;
    --text-main: #333;
    --text-light: #666;
    --price-red: #d0021b;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Roboto', sans-serif;
    color: var(--text-main);
    background-color: #fff;
    line-height: 1.5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

a { text-decoration: none; color: inherit; transition: 0.2s; }

/* 顶部状态栏 */
.top-bar {
    background: #222;
    color: #ccc;
    font-size: 12px;
    padding: 8px 0;
}

.top-bar .container {
    display: flex;
    justify-content: space-between;
}

/* 导航栏 */
.navbar {
    padding: 20px 0;
    border-bottom: 1px solid var(--fs-border);
}

.nav-flex {
    display: flex;
    align-items: center;
    gap: 40px;
}

.logo {
    font-size: 24px;
    font-weight: 700;
    color: var(--fs-blue);
    letter-spacing: -1px;
}

.search-bar {
    flex: 1;
    display: flex;
}

.search-bar input {
    flex: 1;
    padding: 10px 15px;
    border: 1px solid var(--fs-border);
    border-right: none;
    outline: none;
}

.search-bar button {
    background: var(--fs-blue);
    color: white;
    border: none;
    padding: 0 20px;
    cursor: pointer;
}

.nav-icons a {
    margin-left: 20px;
    font-size: 14px;
    font-weight: 500;
}

.cart-btn {
    background: var(--fs-gray-bg);
    padding: 10px 15px;
    border-radius: 4px;
}

/* 分类菜单 */
.category-nav {
    background: #fff;
    border-bottom: 1px solid var(--fs-border);
}

.category-nav .container {
    display: flex;
    gap: 30px;
}

.category-nav a {
    padding: 15px 0;
    font-size: 14px;
    font-weight: 500;
    border-bottom: 2px solid transparent;
}

.category-nav a:hover {
    color: var(--fs-blue);
    border-bottom: 2px solid var(--fs-blue);
}

/* 英雄区 */
.hero {
    background: linear-gradient(135deg, #00448a 0%, #0072e3 100%);
    color: white;
    padding: 60px 0;
}

.hero h1 { font-size: 42px; margin-bottom: 15px; }
.hero p { font-size: 18px; opacity: 0.9; margin-bottom: 30px; }

.hero-actions { display: flex; gap: 15px; }

.btn-blue { background: #fff; color: var(--fs-blue); padding: 12px 25px; font-weight: bold; border-radius: 4px; }
.btn-white { border: 1px solid #fff; color: #fff; padding: 12px 25px; border-radius: 4px; }

/* 产品展示区域 */
.products { padding: 50px 0; background: var(--fs-gray-bg); }

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
}

.product-card {
    background: white;
    border: 1px solid var(--fs-border);
    padding: 20px;
    transition: box-shadow 0.3s;
}

.product-card:hover { box-shadow: 0 10px 20px rgba(0,0,0,0.05); }

/* CSS 模块绘图 */
.module-visual {
    height: 120px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: #fcfcfc;
    margin-bottom: 15px;
    position: relative;
}

.module-body {
    width: 80px;
    height: 15px;
    background: #ccc; /* 银色外壳 */
    border-radius: 2px;
    position: relative;
}

.module-body.wider { width: 100px; height: 18px; }

.pull-tab {
    width: 20px;
    height: 30px;
    margin-top: -2px;
    border-radius: 2px 2px 8px 8px;
    border: 2px solid rgba(0,0,0,0.1);
}

/* 拉环颜色代码 (工业标准) */
.tab-blue { background: #007bff; }   /* 10G SR */
.tab-green { background: #28a745; }  /* 25G SR */
.tab-orange { background: #fd7e14; } /* 40G SR */
.tab-beige { background: #f5f5dc; }  /* 100G SR4 */

.product-info .sku { color: var(--fs-blue); font-size: 12px; font-weight: bold; }
.product-info h3 { font-size: 15px; margin: 5px 0 10px; height: 40px; overflow: hidden; }

.specs {
    list-style: none;
    font-size: 12px;
    color: var(--text-light);
    margin-bottom: 15px;
}

.specs li { padding-bottom: 4px; border-bottom: 1px dashed #eee; margin-bottom: 4px; }

.price-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.price { color: var(--price-red); font-size: 18px; font-weight: 700; }

.btn-add {
    font-size: 12px;
    background: var(--fs-blue);
    color: white;
    padding: 8px 12px;
    border-radius: 3px;
}

/* 信任栏 */
.trust-bar { padding: 40px 0; border-top: 1px solid var(--fs-border); }
.trust-flex { display: flex; justify-content: space-around; text-align: center; }
.trust-item strong { display: block; font-size: 16px; color: var(--fs-blue); }
.trust-item p { font-size: 13px; color: var(--text-light); }

/* 页脚 */
footer { background: #222; color: white; padding: 60px 0 20px; }
.footer-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 50px; margin-bottom: 40px; }
.footer-grid h4 { margin-bottom: 20px; text-transform: uppercase; font-size: 14px; color: #999; }
.footer-grid a { color: #ccc; font-size: 14px; display: inline-block; margin-bottom: 10px; }
.footer-bottom { border-top: 1px solid #333; padding-top: 20px; font-size: 12px; color: #666; text-align: center; }

/* 响应式 */
@media (max-width: 768px) {
    .nav-flex { flex-direction: column; gap: 15px; }
    .search-bar { width: 100%; }
    .footer-grid { grid-template-columns: 1fr; }
}