/* ==================== 全局样式 ==================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #1a73e8;
    --secondary-color: #5f6368;
    --success-color: #34a853;
    --danger-color: #ea4335;
    --warning-color: #fbbc04;
    --dark-color: #202124;
    --light-color: #f8f9fa;
    --border-color: #dadce0;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.12);
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --transition: all 0.3s ease;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--dark-color);
    background: #fff;
}

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

/* ==================== 导航栏 ==================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    padding: 16px 0;
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-color);
}

.nav-brand i {
    font-size: 28px;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-link {
    color: var(--secondary-color);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary-color);
}

/* ==================== 按钮 ==================== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    border: none;
    border-radius: var(--radius-md);
    font-size: 15px;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: #1557b0;
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-outline:hover {
    background: var(--primary-color);
    color: white;
}

.btn-lg {
    padding: 16px 32px;
    font-size: 16px;
}

.btn-block {
    width: 100%;
    justify-content: center;
}

/* ==================== Hero区域 ==================== */
.hero {
    padding: 140px 0 80px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grid" width="100" height="100" patternUnits="userSpaceOnUse"><path d="M 100 0 L 0 0 0 100" fill="none" stroke="rgba(255,255,255,0.1)" stroke-width="1"/></pattern></defs><rect width="100%" height="100%" fill="url(%23grid)"/></svg>');
    opacity: 0.5;
}

.hero-content {
    position: relative;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.hero-title {
    font-size: 56px;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 24px;
    color: var(--dark-color);
}

.gradient-text {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: block;
}

.hero-subtitle {
    font-size: 20px;
    color: var(--secondary-color);
    margin-bottom: 40px;
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 60px;
}

.hero-stats {
    display: flex;
    gap: 60px;
    justify-content: center;
    padding-top: 40px;
    border-top: 1px solid rgba(0,0,0,0.1);
}

.stat-item {
    text-align: center;
}

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

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

/* ==================== 功能特色 ==================== */
.features {
    padding: 100px 0;
    background: white;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-title {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--dark-color);
}

.section-subtitle {
    font-size: 18px;
    color: var(--secondary-color);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.feature-card {
    padding: 32px;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    transition: var(--transition);
}

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

.feature-icon {
    width: 64px;
    height: 64px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    color: white;
    margin-bottom: 24px;
}

.feature-title {
    font-size: 22px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--dark-color);
}

.feature-desc {
    font-size: 15px;
    color: var(--secondary-color);
    line-height: 1.7;
}

/* ==================== 价格套餐 ==================== */
.pricing {
    padding: 100px 0;
    background: var(--light-color);
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.pricing-card {
    background: white;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 40px;
    position: relative;
    transition: var(--transition);
}

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

.pricing-card.featured {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
}

.pricing-badge {
    position: absolute;
    top: -12px;
    right: 32px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 600;
}

.pricing-header {
    text-align: center;
    margin-bottom: 24px;
}

.pricing-title {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--dark-color);
}

.pricing-desc {
    font-size: 15px;
    color: var(--secondary-color);
}

.pricing-price {
    text-align: center;
    margin-bottom: 32px;
    padding-bottom: 32px;
    border-bottom: 1px solid var(--border-color);
}

.price-currency {
    font-size: 24px;
    font-weight: 600;
    color: var(--secondary-color);
    vertical-align: top;
}

.price-amount {
    font-size: 56px;
    font-weight: 800;
    color: var(--dark-color);
}

.price-period {
    font-size: 18px;
    color: var(--secondary-color);
}

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

.pricing-features {
    list-style: none;
    margin-bottom: 32px;
}

.pricing-features li {
    padding: 12px 0;
    font-size: 15px;
    color: var(--secondary-color);
    display: flex;
    align-items: center;
    gap: 12px;
}

.pricing-features li i {
    color: var(--success-color);
    font-size: 16px;
}

/* ==================== 页脚 ==================== */
.footer {
    background: var(--dark-color);
    color: white;
    padding: 60px 0 24px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    margin-bottom: 40px;
}

.footer-title {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.footer-desc {
    color: rgba(255,255,255,0.7);
    font-size: 14px;
    line-height: 1.6;
}

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

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

.footer-links a {
    color: rgba(255,255,255,0.7);
    text-decoration: none;
    font-size: 14px;
    transition: var(--transition);
}

.footer-links a:hover {
    color: white;
}

.footer-bottom {
    text-align: center;
    padding-top: 24px;
    border-top: 1px solid rgba(255,255,255,0.1);
    color: rgba(255,255,255,0.5);
    font-size: 14px;
}

/* ==================== 响应式设计 ==================== */
@media (max-width: 992px) {
    .features-grid,
    .pricing-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .hero-title {
        font-size: 42px;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .features-grid,
    .pricing-grid,
    .footer-content {
        grid-template-columns: 1fr;
    }
    
    .hero-title {
        font-size: 36px;
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 24px;
    }
}