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

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --secondary-color: #8b5cf6;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f9fafb;
    --bg-white: #ffffff;
    --border-color: #e5e7eb;
    --success-color: #10b981;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

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

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

/* 导航栏 */
.navbar {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
    background: rgba(255, 255, 255, 0.95);
}

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

.nav-brand {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
    align-items: center;
}

.nav-menu a {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: color 0.3s;
}

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

.btn-nav {
    padding: 0.5rem 1.5rem;
    background: var(--primary-color);
    color: white !important;
    border-radius: 8px;
    transition: background 0.3s;
}

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

.btn-nav.active {
    background: var(--primary-dark);
}

/* 按钮 */
.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

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

.btn-large {
    padding: 1.125rem 2.5rem;
    font-size: 1.125rem;
}

.btn-full {
    width: 100%;
    text-align: center;
}

/* Hero 区域 */
.hero {
    padding: 6rem 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2.5rem;
    opacity: 0.95;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* 差异区域 */
.differences {
    padding: 5rem 0;
    background: var(--bg-light);
}

.differences h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
}

.diff-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.diff-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
    transition: transform 0.3s;
}

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

.diff-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.diff-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.diff-card p {
    color: var(--text-light);
    line-height: 1.7;
}

/* 功能区域 */
.features {
    padding: 5rem 0;
}

.features h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.section-intro {
    text-align: center;
    font-size: 1.125rem;
    color: var(--text-light);
    max-width: 800px;
    margin: 0 auto 3rem;
    line-height: 1.7;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: var(--bg-light);
    padding: 2rem;
    border-radius: 12px;
    border-left: 4px solid var(--primary-color);
}

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.feature-card p {
    color: var(--text-light);
    margin-bottom: 1.5rem;
    line-height: 1.7;
}

.example {
    background: white;
    padding: 1rem;
    border-radius: 8px;
    border-left: 3px solid var(--secondary-color);
}

.example p {
    font-size: 0.9rem;
    font-style: italic;
    color: var(--text-dark);
    margin-bottom: 0.5rem;
}

.example p:last-child {
    margin-bottom: 0;
}

/* 使用场景对比 */
.use-cases {
    padding: 5rem 0;
    background: var(--bg-light);
}

.use-cases h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
}

.comparison {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.comparison-col {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.comparison-col h3 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
}

.use-cowork {
    border-top: 4px solid var(--success-color);
}

.regular-chat {
    border-top: 4px solid var(--primary-color);
}

.comparison-col ul {
    list-style: none;
}

.comparison-col li {
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-light);
}

.comparison-col li:last-child {
    border-bottom: none;
}

/* 开始使用 */
.getting-started {
    padding: 5rem 0;
}

.getting-started h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
}

.steps-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.step {
    text-align: center;
    padding: 2rem;
}

.step-number {
    width: 60px;
    height: 60px;
    background: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0 auto 1.5rem;
}

.step h3 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
}

.step p {
    color: var(--text-light);
    line-height: 1.7;
}

.tips-section {
    margin-top: 4rem;
    padding-top: 3rem;
    border-top: 2px solid var(--border-color);
}

.tips-section h3 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 2rem;
}

.tips-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.tip-card {
    background: var(--bg-light);
    padding: 2rem;
    border-radius: 12px;
    border-left: 4px solid var(--secondary-color);
}

.tip-card h4 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.tip-card p {
    color: var(--text-light);
    line-height: 1.7;
}

/* CTA 区域 */
.cta {
    padding: 5rem 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
}

.cta h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.cta p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.95;
}

/* 价格页面 */
.pricing-hero {
    padding: 4rem 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
}

.pricing-hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.pricing-hero p {
    font-size: 1.25rem;
    opacity: 0.95;
}

.pricing-section {
    padding: 5rem 0;
    background: var(--bg-light);
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    max-width: 1100px;
    margin: 0 auto;
}

.pricing-card {
    background: white;
    border-radius: 12px;
    padding: 2.5rem;
    box-shadow: var(--shadow);
    transition: transform 0.3s;
    position: relative;
}

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

.pricing-card.featured {
    border: 3px solid var(--primary-color);
    transform: scale(1.05);
}

.pricing-card.featured:hover {
    transform: scale(1.08) translateY(-5px);
}

.badge {
    position: absolute;
    top: -15px;
    right: 20px;
    background: var(--primary-color);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 600;
}

.plan-header {
    text-align: center;
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 2px solid var(--border-color);
}

.plan-header h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.plan-quota {
    font-size: 0.9rem;
    color: var(--primary-color);
    font-weight: 600;
    margin-top: 0.5rem;
}

.price {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 0.25rem;
}

.currency {
    font-size: 1.5rem;
    color: var(--text-light);
}

.amount {
    font-size: 3rem;
    font-weight: 700;
    color: var(--primary-color);
}

.period {
    font-size: 1rem;
    color: var(--text-light);
}

.features-list {
    list-style: none;
    margin-bottom: 2rem;
}

.features-list li {
    padding: 0.75rem 0;
    color: var(--text-light);
    border-bottom: 1px solid var(--border-color);
}

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

/* 对比表 */
.comparison-table-section {
    padding: 5rem 0;
}

.comparison-table-section h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
}

.table-wrapper {
    overflow-x: auto;
}

.comparison-table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.comparison-table thead {
    background: var(--primary-color);
    color: white;
}

.comparison-table th,
.comparison-table td {
    padding: 1.25rem;
    text-align: left;
}

.comparison-table th {
    font-weight: 600;
}

.comparison-table tbody tr {
    border-bottom: 1px solid var(--border-color);
}

.comparison-table tbody tr:last-child {
    border-bottom: none;
}

.comparison-table tbody tr:hover {
    background: var(--bg-light);
}

.comparison-table tr.highlight {
    background: #fef3c7;
}

.comparison-table tr.highlight:hover {
    background: #fde68a;
}

/* FAQ */
.faq-section {
    padding: 5rem 0;
    background: var(--bg-light);
}

.faq-section h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
}

.faq-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.faq-item {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.faq-item h3 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.faq-item p {
    color: var(--text-light);
    line-height: 1.7;
}

/* 页脚 */
.footer {
    background: var(--text-dark);
    color: white;
    padding: 2rem 0;
    text-align: center;
}

.footer p {
    margin-bottom: 0.5rem;
    opacity: 0.8;
}

.footer a {
    color: var(--primary-color);
    text-decoration: none;
}

.footer a:hover {
    text-decoration: underline;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

    .nav-menu {
        gap: 1rem;
        font-size: 0.9rem;
    }

    .differences h2,
    .features h2,
    .use-cases h2,
    .getting-started h2,
    .pricing-hero h1,
    .comparison-table-section h2,
    .faq-section h2 {
        font-size: 2rem;
    }

    .cta h2 {
        font-size: 2rem;
    }

    .pricing-card.featured {
        transform: scale(1);
    }

    .pricing-card.featured:hover {
        transform: translateY(-5px);
    }

    .diff-grid,
    .features-grid,
    .comparison,
    .steps-grid,
    .pricing-grid,
    .faq-grid {
        grid-template-columns: 1fr;
    }
}