/* ===================================
   网站91 - 瀑布流卡片布局
   主题：蓝色科技风
   =================================== */
:root {
    --primary: #0066cc;
    --primary-light: #00a3e0;
    --primary-dark: #004499;
    --accent: #00d4aa;
    --bg-light: #f8fafc;
    --bg-card: #ffffff;
    --text-dark: #1a2a3a;
    --text-gray: #5a6a7a;
    --text-light: #8a9aaa;
    --border: #e2e8f0;
    --shadow: 0 4px 20px rgba(0, 102, 204, 0.1);
    --shadow-hover: 0 8px 40px rgba(0, 102, 204, 0.2);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    background: var(--bg-light);
    color: var(--text-dark);
    line-height: 1.6;
}

a {
    text-decoration: none;
    color: inherit;
}

/* 固定侧边栏导航 */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    width: 260px;
    height: 100vh;
    background: linear-gradient(180deg, var(--primary) 0%, var(--primary-dark) 100%);
    padding: 30px 20px;
    z-index: 1000;
    overflow-y: auto;
}

.logo {
    text-align: center;
    margin-bottom: 40px;
    padding-bottom: 30px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.logo h1 {
    color: #fff;
    font-size: 18px;
    font-weight: 700;
    line-height: 1.4;
    letter-spacing: 1px;
}

.logo p {
    color: rgba(255,255,255,0.7);
    font-size: 12px;
    margin-top: 8px;
}

.nav-menu {
    list-style: none;
}

.nav-menu li {
    margin-bottom: 8px;
}

.nav-menu a {
    display: flex;
    align-items: center;
    padding: 14px 16px;
    color: rgba(255,255,255,0.85);
    border-radius: 10px;
    transition: all 0.3s ease;
    font-size: 14px;
}

.nav-menu a:hover,
.nav-menu a.active {
    background: rgba(255,255,255,0.15);
    color: #fff;
    transform: translateX(5px);
}

.nav-menu .icon {
    width: 22px;
    margin-right: 12px;
    font-size: 16px;
    text-align: center;
}

/* 主内容区 */
.main-content {
    margin-left: 260px;
    min-height: 100vh;
}

/* 英雄区 */
.hero {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 50%, var(--accent) 100%);
    padding: 80px 60px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    border-radius: 50%;
}

.hero-content {
    max-width: 800px;
    position: relative;
    z-index: 1;
}

.hero h2 {
    font-size: 42px;
    color: #fff;
    margin-bottom: 20px;
    line-height: 1.3;
    text-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.hero p {
    font-size: 18px;
    color: rgba(255,255,255,0.9);
    margin-bottom: 30px;
    line-height: 1.8;
}

.hero-btn {
    display: inline-block;
    padding: 16px 36px;
    background: #fff;
    color: var(--primary);
    border-radius: 30px;
    font-weight: 600;
    font-size: 16px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.hero-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

/* 统计数据区 */
.stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    padding: 40px 60px;
    background: #fff;
    border-bottom: 1px solid var(--border);
}

.stat-item {
    text-align: center;
    padding: 25px;
    border-radius: 12px;
    transition: all 0.3s ease;
}

.stat-item:hover {
    background: var(--bg-light);
    transform: translateY(-5px);
}

.stat-number {
    font-size: 36px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 8px;
}

.stat-label {
    font-size: 14px;
    color: var(--text-gray);
}

/* 瀑布流卡片区 */
.waterfall-section {
    padding: 60px;
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header h3 {
    font-size: 32px;
    color: var(--text-dark);
    margin-bottom: 15px;
}

.section-header p {
    font-size: 16px;
    color: var(--text-gray);
    max-width: 600px;
    margin: 0 auto;
}

.waterfall-grid {
    column-count: 3;
    column-gap: 25px;
}

.waterfall-card {
    background: var(--bg-card);
    border-radius: 16px;
    padding: 28px;
    margin-bottom: 25px;
    break-inside: avoid;
    box-shadow: var(--shadow);
    transition: all 0.4s ease;
    border: 1px solid var(--border);
}

.waterfall-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-hover);
}

.card-icon {
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, var(--primary-light), var(--accent));
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 26px;
    margin-bottom: 18px;
}

.waterfall-card h4 {
    font-size: 20px;
    color: var(--text-dark);
    margin-bottom: 12px;
}

.waterfall-card p {
    font-size: 14px;
    color: var(--text-gray);
    line-height: 1.7;
}

/* 不同高度的卡片 */
.waterfall-card.tall {
    min-height: 320px;
}

.waterfall-card.medium {
    min-height: 260px;
}

.waterfall-card.short {
    min-height: 200px;
}

/* 功能亮点区 */
.features {
    padding: 60px;
    background: #fff;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 25px;
}

.feature-card {
    background: var(--bg-light);
    border-radius: 16px;
    padding: 35px;
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid var(--border);
}

.feature-card:hover {
    background: #fff;
    box-shadow: var(--shadow-hover);
    transform: translateY(-5px);
}

.feature-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--primary), var(--accent));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 32px;
    margin: 0 auto 20px;
}

.feature-card h4 {
    font-size: 18px;
    color: var(--text-dark);
    margin-bottom: 12px;
}

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

/* 价格区 */
.pricing {
    padding: 60px;
    background: var(--bg-light);
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 25px;
}

.price-card {
    background: #fff;
    border-radius: 20px;
    padding: 40px 30px;
    text-align: center;
    transition: all 0.3s ease;
    border: 2px solid var(--border);
}

.price-card.featured {
    border-color: var(--primary);
    transform: scale(1.05);
    box-shadow: var(--shadow-hover);
}

.price-card:hover {
    transform: translateY(-8px);
}

.price-card.featured:hover {
    transform: scale(1.05) translateY(-8px);
}

.price-header {
    margin-bottom: 25px;
}

.price-header h4 {
    font-size: 22px;
    color: var(--text-dark);
    margin-bottom: 8px;
}

.price {
    font-size: 42px;
    font-weight: 700;
    color: var(--primary);
}

.price span {
    font-size: 16px;
    color: var(--text-gray);
    font-weight: 400;
}

.price-features {
    list-style: none;
    margin-bottom: 30px;
}

.price-features li {
    padding: 12px 0;
    border-bottom: 1px solid var(--border);
    font-size: 14px;
    color: var(--text-gray);
}

.price-features li:last-child {
    border-bottom: none;
}

.price-btn {
    display: inline-block;
    padding: 14px 40px;
    background: var(--primary);
    color: #fff;
    border-radius: 25px;
    font-weight: 600;
    transition: all 0.3s ease;
}

.price-btn:hover {
    background: var(--primary-dark);
}

/* 案例区 */
.cases {
    padding: 60px;
    background: #fff;
}

.cases-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
}

.case-card {
    background: var(--bg-light);
    border-radius: 16px;
    overflow: hidden;
    transition: all 0.3s ease;
    border: 1px solid var(--border);
}

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

.case-image {
    height: 180px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 60px;
}

.case-content {
    padding: 25px;
}

.case-content h4 {
    font-size: 20px;
    color: var(--text-dark);
    margin-bottom: 10px;
}

.case-content p {
    font-size: 14px;
    color: var(--text-gray);
    margin-bottom: 15px;
}

.case-stats {
    display: flex;
    gap: 20px;
}

.case-stat {
    font-size: 13px;
    color: var(--primary);
    font-weight: 600;
}

/* CTA区 */
.cta {
    padding: 60px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    text-align: center;
}

.cta h3 {
    font-size: 32px;
    color: #fff;
    margin-bottom: 15px;
}

.cta p {
    font-size: 16px;
    color: rgba(255,255,255,0.9);
    margin-bottom: 30px;
}

.cta-btn {
    display: inline-block;
    padding: 16px 50px;
    background: #fff;
    color: var(--primary);
    border-radius: 30px;
    font-weight: 600;
    font-size: 16px;
    transition: all 0.3s ease;
}

.cta-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}

/* 页脚 */
.footer {
    background: var(--text-dark);
    padding: 50px 60px;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-brand h4 {
    font-size: 20px;
    color: #fff;
    margin-bottom: 15px;
}

.footer-brand p {
    font-size: 14px;
    color: rgba(255,255,255,0.6);
    line-height: 1.8;
}

.footer-links h5 {
    font-size: 16px;
    color: #fff;
    margin-bottom: 20px;
}

.footer-links ul {
    list-style: none;
}

.footer-links li {
    margin-bottom: 12px;
}

.footer-links a {
    font-size: 14px;
    color: rgba(255,255,255,0.6);
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: #fff;
}

.footer-contact p {
    font-size: 14px;
    color: rgba(255,255,255,0.6);
    margin-bottom: 10px;
}

.footer-contact strong {
    color: #fff;
}

.footer-bottom {
    padding-top: 30px;
    border-top: 1px solid rgba(255,255,255,0.1);
    text-align: center;
    font-size: 14px;
    color: rgba(255,255,255,0.4);
}

/* 响应式 */
@media (max-width: 1200px) {
    .waterfall-grid {
        column-count: 2;
    }

    .features-grid,
    .pricing-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 992px) {
    .sidebar {
        transform: translateX(-100%);
    }

    .main-content {
        margin-left: 0;
    }

    .stats {
        grid-template-columns: repeat(2, 1fr);
    }

    .cases-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .hero {
        padding: 60px 30px;
    }

    .hero h2 {
        font-size: 28px;
    }

    .stats {
        grid-template-columns: 1fr 1fr;
        padding: 30px;
    }

    .waterfall-section,
    .features,
    .pricing,
    .cases,
    .cta,
    .footer {
        padding: 40px 20px;
    }

    .waterfall-grid {
        column-count: 1;
    }

    .features-grid,
    .pricing-grid {
        grid-template-columns: 1fr;
    }

    .price-card.featured {
        transform: none;
    }
}

@media (max-width: 480px) {
    .hero h2 {
        font-size: 24px;
    }

    .section-header h3 {
        font-size: 24px;
    }

    .stat-number {
        font-size: 28px;
    }
}