/* ==================== 基础样式 ==================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI", Roboto, "Microsoft YaHei", sans-serif;
    color: #1d1d1f;
    background: #fff;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

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

/* ==================== 导航栏 - 苹果风格 ==================== */
.apple-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.nav-container {
    max-width: 1024px;
    margin: 0 auto;
    padding: 0 22px;
    height: 48px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo {
    font-size: 21px;
    font-weight: 600;
    color: #1d1d1f;
    letter-spacing: -0.02em;
}

.nav-links {
    display: flex;
    gap: 32px;
    list-style: none;
}

.nav-links a {
    font-size: 14px;
    color: #1d1d1f;
    opacity: 0.8;
    transition: opacity 0.3s;
}

.nav-links a:hover {
    opacity: 1;
}

/* ==================== Hero 区域 ==================== */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 120px 24px 80px;
    background: linear-gradient(180deg, #fbfbfd 0%, #f5f5f7 100%);
}

.hero-title {
    font-size: 80px;
    font-weight: 700;
    letter-spacing: -0.04em;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 16px;
}

.hero-subtitle {
    font-size: 28px;
    font-weight: 600;
    color: #1d1d1f;
    margin-bottom: 16px;
    letter-spacing: -0.02em;
}

.hero-description {
    font-size: 19px;
    color: #86868b;
    max-width: 600px;
}

/* ==================== 模块卡片 ==================== */
.modules-section {
    padding: 80px 24px 120px;
    background: #fff;
}

.module-grid {
    max-width: 1024px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.module-card {
    background: #f5f5f7;
    border-radius: 24px;
    padding: 48px 32px;
    text-align: center;
    transition: all 0.5s cubic-bezier(0.25, 0.1, 0.25, 1);
    position: relative;
    overflow: hidden;
}

.module-card:hover {
    background: #000;
    color: #fff;
    transform: translateY(-8px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
}

.module-card:hover .module-icon {
    transform: scale(1.1);
}

.module-card:hover .module-arrow {
    transform: translateX(10px);
    opacity: 1;
}

.module-icon {
    font-size: 64px;
    margin-bottom: 24px;
    transition: transform 0.5s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.module-card h2 {
    font-size: 28px;
    font-weight: 600;
    letter-spacing: -0.02em;
    margin-bottom: 12px;
}

.module-card p {
    font-size: 15px;
    color: #86868b;
    line-height: 1.5;
    margin-bottom: 20px;
}

.module-card:hover p {
    color: rgba(255, 255, 255, 0.7);
}

.module-meta {
    display: flex;
    justify-content: center;
    gap: 16px;
    font-size: 13px;
    color: #86868b;
}

.module-card:hover .module-meta {
    color: rgba(255, 255, 255, 0.5);
}

.module-arrow {
    position: absolute;
    right: 24px;
    bottom: 24px;
    font-size: 24px;
    opacity: 0;
    transition: all 0.3s;
}

/* ==================== 数据统计 ==================== */
.stats-section {
    background: #f5f5f7;
    padding: 80px 24px;
}

.stats-container {
    max-width: 1024px;
    margin: 0 auto;
    display: flex;
    justify-content: space-around;
    text-align: center;
}

.stat-item {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: 56px;
    font-weight: 700;
    color: #1d1d1f;
    letter-spacing: -0.02em;
}

.stat-label {
    font-size: 15px;
    color: #86868b;
    margin-top: 8px;
}

/* ==================== 特色内容 ==================== */
.featured-section {
    padding: 120px 24px;
    background: #fff;
}

.section-title {
    text-align: center;
    font-size: 56px;
    font-weight: 700;
    letter-spacing: -0.03em;
    margin-bottom: 60px;
}

.featured-grid {
    max-width: 1024px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-template-rows: repeat(2, 300px);
    gap: 16px;
}

.featured-item {
    border-radius: 20px;
    overflow: hidden;
    position: relative;
    cursor: pointer;
    transition: transform 0.5s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.featured-item:hover {
    transform: scale(0.98);
}

.featured-large {
    grid-column: span 2;
    grid-row: span 2;
}

.featured-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    transition: transform 0.5s;
}

.featured-item:hover .featured-bg {
    transform: scale(1.05);
}

.featured-content {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 32px;
    color: #fff;
    background: linear-gradient(transparent, rgba(0, 0, 0, 0.7));
}

.featured-tag {
    display: inline-block;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    background: rgba(255, 255, 255, 0.2);
    padding: 4px 12px;
    border-radius: 12px;
    margin-bottom: 12px;
}

.featured-content h3 {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 8px;
}

.featured-large .featured-content h3 {
    font-size: 36px;
}

.featured-content p {
    font-size: 15px;
    opacity: 0.8;
}

/* ==================== 底部 ==================== */
.apple-footer {
    background: #f5f5f7;
    padding: 60px 24px;
    text-align: center;
}

.footer-content p {
    font-size: 13px;
    color: #86868b;
}

.footer-note {
    margin-top: 8px;
}

/* ==================== 响应式 ==================== */
@media (max-width: 1024px) {
    .module-grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }

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

    .featured-large {
        grid-column: span 2;
        grid-row: span 1;
    }

    .featured-item {
        height: 250px;
    }

    .featured-large {
        height: 350px;
    }
}

@media (max-width: 768px) {
    .hero-title {
        font-size: 48px;
    }

    .hero-subtitle {
        font-size: 20px;
    }

    .hero-description {
        font-size: 16px;
    }

    .section-title {
        font-size: 36px;
    }

    .stats-container {
        flex-wrap: wrap;
        gap: 40px;
    }

    .stat-number {
        font-size: 40px;
    }

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

    .featured-large {
        grid-column: span 1;
    }
}