/* ============================================================
   全局样式 - 长城环迅
   ============================================================ */

:root {
    --primary: #1A3A6A;
    --primary-dark: #0F2847;
    --primary-light: #E8F0F8;
    --primary-bg: #F5F8FC;
    --accent: #D4A843;
    --gradient: linear-gradient(135deg, #1A3A6A, #2D5A8A);
    --text-dark: #1A2332;
    --text-muted: #5A6B7C;
    --white: #FFFFFF;
    --shadow: 0 8px 30px rgba(26,58,106,0.12);
    --shadow-hover: 0 12px 40px rgba(26,58,106,0.2);
    --radius: 12px;
    --transition: all 0.3s ease;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-dark);
    line-height: 1.6;
    background: var(--white);
    margin: 0;
    padding: 0;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ============================================================
   Logo 样式
   ============================================================ */
.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 36px;
    font-weight: 700;
}

.logo .logo-icon {
    background: var(--gradient);
    color: var(--white);
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
}

.logo .logo-text {
    color: #1A3A6A;
    font-size: 36px;
    letter-spacing: 1px;
}

/* ============================================================
   导航栏
   ============================================================ */
.navbar {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.06);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 12px 0;
    margin: 0;
    width: 100%;
}

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
    align-items: center;
}

.nav-menu a {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: var(--transition);
    font-size: 15px;
}

.nav-menu a:hover {
    color: var(--primary);
}

.nav-menu a.active {
    color: var(--primary);
    position: relative;
}

.nav-menu a.active::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--gradient);
    border-radius: 2px;
}

.nav-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 28px;
    cursor: pointer;
    color: var(--text-dark);
}

/* ============================================================
   按钮样式
   ============================================================ */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-size: 15px;
    text-align: center;
}

.btn-primary {
    background: var(--gradient);
    color: #FFFFFF !important;
    box-shadow: 0 4px 15px rgba(26,58,106,0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(26,58,106,0.4);
}

.btn-sm {
    padding: 8px 20px;
    font-size: 13px;
}

.btn-block {
    display: block;
    width: 100%;
}

/* 菜单中的登录按钮 */
.nav-menu .btn-primary {
    color: #FFFFFF !important;
}

.nav-menu .btn-primary:hover {
    color: #FFFFFF !important;
}

/* ============================================================
   通用标题
   ============================================================ */
.section-title {
    font-size: 32px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 40px;
    color: var(--text-dark);
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: var(--gradient);
    margin: 12px auto 0;
    border-radius: 2px;
}

/* ============================================================
   优势区域
   ============================================================ */
.advantages {
    padding: 70px 0;
    background: var(--primary-bg);
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
}

.advantage-card {
    background: var(--white);
    padding: 30px 24px;
    border-radius: var(--radius);
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.advantage-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.advantage-icon {
    font-size: 40px;
    margin-bottom: 16px;
}

.advantage-card h3 {
    font-size: 18px;
    margin-bottom: 10px;
}

.advantage-card p {
    color: var(--text-muted);
    font-size: 14px;
}

/* ============================================================
   机柜区域
   ============================================================ */
.products {
    padding: 70px 0;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.product-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 30px 24px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid #f0f4f8;
    position: relative;
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
    border-color: var(--primary);
}

.product-tag {
    position: absolute;
    top: 12px;
    right: 12px;
    background: var(--accent);
    color: var(--white);
    padding: 4px 14px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.product-card h3 {
    font-size: 20px;
    margin-bottom: 12px;
}

.product-specs {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 16px;
    color: var(--text-muted);
    font-size: 14px;
}

.product-specs span {
    background: var(--primary-bg);
    padding: 4px 12px;
    border-radius: 6px;
}

.product-price {
    margin: 16px 0 8px;
}

.product-price .price {
    font-size: 32px;
    font-weight: 700;
    color: var(--primary-dark);
}

.product-price .period {
    color: var(--text-muted);
    font-size: 14px;
}

.product-bandwidth {
    color: var(--text-muted);
    font-size: 14px;
    margin-bottom: 16px;
    padding: 8px 0;
    border-top: 1px solid #f0f4f8;
}

/* ============================================================
   资讯区域
   ============================================================ */
.news {
    padding: 70px 0;
    background: var(--primary-bg);
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.news-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.news-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-hover);
}

.news-category {
    display: inline-block;
    background: var(--primary-light);
    color: var(--primary);
    padding: 2px 14px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    margin-bottom: 10px;
}

.news-card h3 {
    font-size: 18px;
    margin-bottom: 10px;
}

.news-card h3 a {
    color: var(--text-dark);
    text-decoration: none;
    transition: var(--transition);
}

.news-card h3 a:hover {
    color: var(--primary);
}

.news-card p {
    color: var(--text-muted);
    font-size: 14px;
    margin-bottom: 12px;
}

.news-meta {
    display: flex;
    justify-content: space-between;
    color: var(--text-muted);
    font-size: 13px;
    border-top: 1px solid #f0f4f8;
    padding-top: 12px;
}

/* ============================================================
   公司数据统计
   ============================================================ */
.company-stats {
    background: var(--gradient);
    padding: 60px 0;
    color: #fff;
}

.company-stats .stats-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 20px;
    text-align: center;
}

.company-stats .stats-grid .stat-item .number {
    font-size: 36px;
    font-weight: 800;
    color: #D4A843;
    display: block;
}

.company-stats .stats-grid .stat-item .label {
    font-size: 14px;
    opacity: 0.8;
    margin-top: 4px;
}

/* ============================================================
   页面横幅 - 通用
   ============================================================ */
.page-banner {
    background: linear-gradient(135deg, #0A1628, #1A3A6A);
    padding: 60px 0 40px;
    text-align: center;
    color: #fff;
    margin: 0;
}

.page-banner h1 {
    font-size: 40px;
    font-weight: 700;
    margin-bottom: 10px;
}

.page-banner p {
    font-size: 18px;
    opacity: 0.8;
}

/* ============================================================
   页脚
   ============================================================ */
.footer {
    background: #0F1A2E;
    color: rgba(255, 255, 255, 0.7);
    padding: 50px 0 20px;
    margin: 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
    margin-bottom: 30px;
}

.footer h4 {
    color: var(--white);
    font-size: 18px;
    margin-bottom: 16px;
}

.footer ul {
    list-style: none;
}

.footer ul li {
    margin-bottom: 8px;
}

.footer ul a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: var(--transition);
}

.footer ul a:hover {
    color: var(--white);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 20px;
    text-align: center;
    font-size: 14px;
}

/* ============================================================
   响应式适配
   ============================================================ */

/* 平板端 */
@media (max-width: 1024px) {
    .advantages-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .products-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .news-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .company-stats .stats-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* 手机端 */
@media (max-width: 768px) {
    /* 导航 */
    .nav-toggle {
        display: block;
    }

    .nav-menu {
        display: none;
        flex-direction: column;
        width: 100%;
        padding: 20px 0;
        gap: 15px;
        background: var(--white);
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    }

    .nav-menu.active {
        display: flex;
    }

    /* Logo 手机端适配 */
    .logo {
        font-size: 28px;
    }
    .logo .logo-text {
        font-size: 28px;
    }
    .logo .logo-icon {
        width: 38px;
        height: 38px;
        font-size: 18px;
    }

    /* 布局 */
    .advantages-grid,
    .products-grid,
    .news-grid {
        grid-template-columns: 1fr;
    }
    .footer-grid {
        grid-template-columns: 1fr;
    }
    .section-title {
        font-size: 26px;
    }

    /* 公司数据 */
    .company-stats .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .company-stats .stats-grid .stat-item .number {
        font-size: 28px;
    }

    /* 页面横幅 */
    .page-banner {
        padding: 40px 0 30px;
    }
    .page-banner h1 {
        font-size: 28px;
    }
    .page-banner p {
        font-size: 15px;
    }
}

/* 小屏手机 */
@media (max-width: 480px) {
    .logo {
        font-size: 24px;
    }
    .logo .logo-text {
        font-size: 24px;
    }
    .logo .logo-icon {
        width: 32px;
        height: 32px;
        font-size: 16px;
    }

    .company-stats .stats-grid {
        grid-template-columns: 1fr 1fr;
    }
    .company-stats .stats-grid .stat-item .number {
        font-size: 22px;
    }
}

/* 超大屏 */
@media (min-width: 1920px) {
    .logo {
        font-size: 44px;
    }
    .logo .logo-text {
        font-size: 44px;
    }
    .logo .logo-icon {
        width: 56px;
        height: 56px;
        font-size: 28px;
    }
}