/* ================= 基础变量 ================= */
:root {
    --primary-color: #0052cc; --hover-color: #003d99; --bg-color: #f4f7f9;
    --text-main: #333333; --text-muted: #666666; --white: #ffffff;
    --border-color: #eaedf2; --shadow: 0 4px 12px rgba(0,0,0,0.05);
    --transition: all 0.3s ease;
}

* { margin: 0; padding: 0; box-sizing: border-box; font-family: 'Helvetica Neue', Helvetica, 'PingFang SC', Arial, sans-serif; }
body { background-color: var(--bg-color); color: var(--text-main); line-height: 1.6; }
a { text-decoration: none; color: inherit; }
html { scroll-behavior: smooth; }

/* ================= 顶部 & 导航 & 语言切换 ================= */
.header-top { background-color: var(--white); border-bottom: 1px solid var(--border-color); padding: 15px 5%; display: flex; justify-content: space-between; align-items: center; }
.logo { font-size: 24px; font-weight: bold; color: var(--primary-color); display: flex; align-items: center; gap: 10px; }
.logo i { font-size: 28px; }
.top-actions { display: flex; align-items: center; gap: 20px; }

/* 语言切换菜单核心代码 */
.lang-switch { position: relative; cursor: pointer; color: var(--text-muted); font-size: 14px; padding: 10px 0; }
.lang-switch:hover .lang-menu { display: block; }
.lang-menu { display: none; position: absolute; top: 100%; right: 0; background: var(--white); box-shadow: var(--shadow); border-radius: 4px; overflow: hidden; z-index: 100; min-width: 100px; }
.lang-menu a { display: block; padding: 10px 15px; border-bottom: 1px solid var(--border-color); transition: var(--transition); }
.lang-menu a:hover { background-color: var(--bg-color); color: var(--primary-color); }

.btn-register { background-color: var(--primary-color); color: var(--white); padding: 8px 24px; border-radius: 20px; font-size: 14px; font-weight: 500; transition: var(--transition); }
.btn-register:hover { background-color: var(--hover-color); color: var(--white); }

.nav-bar { background-color: var(--white); padding: 15px 5%; box-shadow: var(--shadow); display: flex; gap: 30px; justify-content: center; flex-wrap: wrap; position: sticky; top: 0; z-index: 90; }
.nav-bar a { font-size: 15px; color: var(--text-main); font-weight: 500; transition: var(--transition); }
.nav-bar a:hover { color: var(--primary-color); }

/* ================= 主体与产品模块 ================= */
.container { max-width: 1200px; margin: 40px auto; padding: 0 20px; }
.main-category { scroll-margin-top: 80px; margin-bottom: 80px; }
.category-title { font-size: 30px; text-align: center; margin-bottom: 40px; color: var(--text-main); padding-bottom: 15px; border-bottom: 2px solid var(--border-color); }
.region-group { margin-bottom: 40px; }
.region-title { font-size: 20px; border-left: 4px solid var(--primary-color); padding-left: 10px; margin-bottom: 20px; display: flex; align-items: center; gap: 10px; }

/* ================= 通用带宽切换组件 (完全不依赖具体产品) ================= */
.product-row { background: var(--white); border-radius: 8px; padding: 20px 30px; margin-bottom: 15px; display: flex; justify-content: space-between; align-items: center; box-shadow: var(--shadow); transition: var(--transition); border: 1px solid transparent; }
.product-row:hover { transform: translateY(-2px); border-color: #d1dff5; box-shadow: 0 8px 20px rgba(0,82,204,0.1); }
.specs { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; flex: 1; }
.spec-item { font-size: 15px; color: var(--text-muted); background: var(--bg-color); padding: 5px 12px; border-radius: 4px; }
.spec-item span { color: var(--text-main); font-weight: 600; }

.bw-labels { flex-basis: 100%; display: flex; gap: 10px; margin-top: 8px; flex-wrap: wrap; }
.bw-labels label { padding: 5px 12px; border: 1px solid var(--border-color); border-radius: 4px; font-size: 13px; color: var(--text-muted); cursor: pointer; transition: var(--transition); background: var(--white); user-select: none; }
.bw-labels label:hover { border-color: var(--primary-color); color: var(--primary-color); }

.price-action { display: flex; align-items: center; gap: 30px; min-width: 200px; justify-content: flex-end; }
.price { font-size: 24px; color: #ff4d4f; font-weight: bold; }
.price span { font-size: 14px; color: var(--text-muted); font-weight: normal; }
.btn-order { background-color: transparent; color: var(--primary-color); border: 1px solid var(--primary-color); padding: 8px 25px; border-radius: 4px; cursor: pointer; transition: var(--transition); white-space: nowrap; }
.btn-order:hover { background-color: var(--primary-color); color: var(--white); }

/* 隐藏原生单选框和所有价格 */
.product-row input[type="radio"] { display: none; }
.product-row .price { display: none; }

/* 带宽选项高亮绑定 */
.product-row input.bw-10:checked ~ .specs .bw-labels .lbl-10,
.product-row input.bw-20:checked ~ .specs .bw-labels .lbl-20,
.product-row input.bw-30:checked ~ .specs .bw-labels .lbl-30,
.product-row input.bw-50:checked ~ .specs .bw-labels .lbl-50,
.product-row input.bw-100:checked ~ .specs .bw-labels .lbl-100 {
    background-color: var(--primary-color); color: var(--white); border-color: var(--primary-color);
}

/* 带宽价格显示绑定 */
.product-row input.bw-10:checked ~ .price-action .p-10,
.product-row input.bw-20:checked ~ .price-action .p-20,
.product-row input.bw-30:checked ~ .price-action .p-30,
.product-row input.bw-50:checked ~ .price-action .p-50,
.product-row input.bw-100:checked ~ .price-action .p-100 { display: block; }

/* ================= 悬浮客服 ================= */
.floating-service { position: fixed; bottom: 40px; right: 40px; z-index: 999; }
.service-btn { width: 60px; height: 60px; border-radius: 50%; background-color: var(--primary-color); color: var(--white); display: flex; justify-content: center; align-items: center; font-size: 24px; cursor: pointer; box-shadow: 0 4px 15px rgba(0,82,204,0.4); transition: var(--transition); }
.service-btn:hover { transform: scale(1.05); }
.service-menu { position: absolute; bottom: 75px; right: 0; background: var(--white); border-radius: 8px; box-shadow: 0 5px 25px rgba(0,0,0,0.15); padding: 10px; display: none; flex-direction: column; gap: 10px; min-width: 150px; }
.floating-service:hover .service-menu { display: flex; }
.service-menu a { display: flex; align-items: center; gap: 10px; padding: 10px 15px; border-radius: 6px; color: var(--text-main); font-weight: 500; transition: var(--transition); }
.service-menu a i { font-size: 20px; }
.service-menu a.tg:hover { background-color: #f0f8ff; color: #0088cc; }
.service-menu a.wa:hover { background-color: #f0fff4; color: #25D366; }
.tg i { color: #0088cc; } .wa i { color: #25D366; }

/* 页脚与响应式 */
footer { background-color: #2c3e50; color: rgba(255,255,255,0.7); text-align: center; padding: 25px; font-size: 14px; margin-top: 40px; }
@media (max-width: 768px) { .product-row { flex-direction: column; align-items: flex-start; gap: 20px; } .price-action { width: 100%; justify-content: space-between; } .nav-bar { gap: 15px; } .header-top { flex-direction: column; gap: 15px; } }