:root {
    /* 颜色系统 */
    --color-bg: #000000;
    --color-bg-secondary: #0a0a0a;
    --color-bg-tertiary: #111111;
    --color-text-primary: #ffffff;
    --color-text-secondary: #999999;
    --color-text-tertiary: #666666;
    --color-accent: #3b82f6;
    --color-accent-hover: #2563eb;
    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-error: #ef4444;

    /* 渐变 */
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-accent: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
    --gradient-text: linear-gradient(135deg, #ffffff 0%, #999999 100%);

    /* 阴影 */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.5);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 20px rgba(59, 130, 246, 0.3);

    /* 字体 */
    --font-sans: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'Fira Code', 'Consolas', monospace;

    /* 间距 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;

    /* 圆角 */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* 动画 */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* 重置样式 */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-sans);
    background-color: var(--color-bg);
    color: var(--color-text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

a {
    text-decoration: none;
}

a:hover,
a:focus {
    text-decoration: none;
}

/* 导航栏 */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 70px;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    z-index: 1000;
    transition: all var(--transition-base);
}

.nav.scrolled {
    height: 60px;
    background: rgba(0, 0, 0, 0.95);
    box-shadow: var(--shadow-lg);
}

.nav-content {
    max-width: 1280px;
    margin: 0 auto;
    height: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 var(--spacing-xl);
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-text-primary);
    transition: all var(--transition-fast);
}

.nav-logo svg {
    color: var(--color-accent);
}

.nav-logo:hover {
    transform: translateY(-2px);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
}

.nav-link {
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    transition: color var(--transition-fast);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-accent);
    transition: width var(--transition-base);
}

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

.nav-link:hover::after {
    width: 100%;
}

.btn-nav {
    padding: 0.5rem 1.25rem;
    background: var(--color-accent);
    color: white;
    border-radius: var(--radius-full);
    font-size: 0.9375rem;
    font-weight: 600;
    transition: all var(--transition-fast);
}

.btn-nav:hover {
    background: var(--color-accent-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 0.375rem;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-text-primary);
    transition: all var(--transition-base);
}

/* Hero 区域 */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 120px var(--spacing-xl) 80px;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
}

#particles-canvas {
    width: 100%;
    height: 100%;
}

.hero-container {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 900px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: 0.5rem 1rem;
    background: rgba(59, 130, 246, 0.1);
    border: 1px solid rgba(59, 130, 246, 0.2);
    border-radius: var(--radius-full);
    font-size: 0.875rem;
    color: var(--color-accent);
    margin-bottom: var(--spacing-xl);
}

.badge-dot {
    width: 8px;
    height: 8px;
    background: var(--color-accent);
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.hero-title {
    font-size: clamp(3rem, 8vw, 5rem);
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: var(--spacing-lg);
    letter-spacing: -0.02em;
}

.gradient-text {
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: clamp(1rem, 2.5vw, 1.25rem);
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-2xl);
    line-height: 1.8;
}

.hero-cta {
    display: flex;
    gap: var(--spacing-lg);
    justify-content: center;
    margin-bottom: var(--spacing-3xl);
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: 0.875rem 1.75rem;
    border-radius: var(--radius-full);
    font-size: 1rem;
    font-weight: 600;
    transition: all var(--transition-base);
    cursor: pointer;
    border: none;
    text-decoration: none;
    line-height: 1;
    white-space: nowrap;
}

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

.btn-primary:hover {
    background: var(--color-accent-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.05);
    color: var(--color-text-primary);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

.btn.large {
    padding: 1.125rem 2.25rem;
    font-size: 1.125rem;
}

.hero-stats {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: var(--spacing-2xl);
    padding: var(--spacing-xl);
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-2xl);
    backdrop-filter: blur(10px);
}

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

.stat-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-xs);
}

.stat-label {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
}

.hero-scroll {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--color-text-tertiary);
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

.scroll-indicator {
    width: 2px;
    height: 40px;
    background: linear-gradient(to bottom, var(--color-accent), transparent);
    animation: scroll-animation 2s ease-in-out infinite;
}

@keyframes scroll-animation {
    0%, 100% { opacity: 0.3; transform: translateY(0); }
    50% { opacity: 1; transform: translateY(10px); }
}

/* 通用区域 */
.container {
    max-width: 1440px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-3xl);
}

.section-title {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
    font-weight: 800;
    margin-bottom: var(--spacing-md);
    letter-spacing: -0.02em;
}

.section-subtitle {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
}

/* 功能区域 */
.features {
    padding: 120px 0;
    background: var(--color-bg-secondary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: var(--spacing-xl);
}

.feature-card {
    padding: var(--spacing-2xl);
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-xl);
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(600px circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(59, 130, 246, 0.1), transparent 40%);
    opacity: 0;
    transition: opacity var(--transition-base);
}

.feature-card:hover {
    transform: translateY(-8px);
    border-color: rgba(59, 130, 246, 0.2);
    box-shadow: var(--shadow-xl);
}

.feature-card:hover::before {
    opacity: 1;
}

.feature-card.large {
    grid-column: span 2;
}

.feature-icon {
    width: 64px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(59, 130, 246, 0.1);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-lg);
    color: var(--color-accent);
}

.feature-card h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.feature-card p {
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-lg);
}

.feature-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.feature-list li {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--color-text-secondary);
    font-size: 0.9375rem;
}

.feature-list svg {
    flex-shrink: 0;
    color: var(--color-success);
}

/* 工作原理区域 */
.how-it-works {
    padding: 120px 0;
    background: var(--color-bg);
}

.steps-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-2xl);
    margin-top: var(--spacing-3xl);
}

.step-item {
    flex: 1;
    text-align: center;
}

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

.step-content h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.step-content p {
    color: var(--color-text-secondary);
    line-height: 1.8;
}

.step-visual {
    margin-top: var(--spacing-lg);
}

.visual-box {
    width: 120px;
    height: 120px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-xl);
    margin: 0 auto;
    color: var(--color-accent);
}

.step-arrow {
    font-size: 2rem;
    color: var(--color-text-tertiary);
    flex-shrink: 0;
}

/* CTA 区域 */
.cta {
    padding: 120px 0;
    background: var(--color-bg-secondary);
    position: relative;
    overflow: hidden;
}

.cta::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.15), transparent 70%);
    pointer-events: none;
}

.cta-content {
    text-align: center;
    position: relative;
    z-index: 1;
}

.cta-content h2 {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 800;
    margin-bottom: var(--spacing-md);
}

.cta-content p {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-2xl);
}

.cta-buttons {
    display: flex;
    gap: var(--spacing-lg);
    justify-content: center;
}


/* 价格区域 */
.pricing {
    padding: 120px 0;
    background: var(--color-bg);
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
}

.plan-card {
    padding: var(--spacing-2xl);
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: var(--radius-xl);
    transition: all var(--transition-base);
}

.plan-card:hover {
    transform: translateY(-6px);
    border-color: rgba(59, 130, 246, 0.25);
    box-shadow: var(--shadow-xl);
}

.plan-header {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    margin-bottom: var(--spacing-lg);
}

.plan-name {
    font-size: 1.5rem;
    font-weight: 800;
}

.plan-price {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
}

.plan-features {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    margin: var(--spacing-lg) 0;
    color: var(--color-text-secondary);
}

.plan-cta {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.plan-cta .btn {
    justify-content: center;
    min-width: 160px;
}

.table-responsive {
    width: 100%;
    overflow-x: auto;
}

.pricing-table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
}

.pricing-table thead th {
    background: rgba(59, 130, 246, 0.10);
    color: var(--color-text-primary);
    font-weight: 700;
}

.pricing-table th,
.pricing-table td {
    padding: var(--spacing-lg);
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    color: var(--color-text-secondary);
    line-height: 1.7;
}

.pricing-table td:first-child,
.pricing-table th:first-child {
    text-align: left;
    color: var(--color-text-primary);
}

.pricing-table tbody tr:nth-child(odd) {
    background: rgba(255, 255, 255, 0.02);
}

.pricing-table tbody tr:hover {
    background: rgba(255, 255, 255, 0.04);
}

.pricing-table .plan-header-cell {
    color: var(--color-text-primary);
}

.pricing-table .price-badge {
    display: inline;
    margin: 0;
    padding: 0;
    border: none;
    border-radius: 0;
    background: transparent;
    font-size: inherit;
    color: var(--color-text-secondary);
}

.pricing-table .cell-cta {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
}

.pricing-table .cell-cta .btn {
    min-width: 140px;
}

/* 页脚 */
.footer {
    padding: 80px 0 40px;
    background: var(--color-bg);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr repeat(2, 1fr);
    gap: var(--spacing-3xl);
    margin-bottom: var(--spacing-3xl);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.footer-logo svg {
    color: var(--color-accent);
}

.footer-desc {
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: var(--spacing-lg);
}

.footer-social {
    display: flex;
    gap: var(--spacing-md);
}

.footer-social:empty,
.footer-social:not(:has(a)) {
    display: none;
}

.footer-social a {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 50%;
    color: var(--color-text-secondary);
    transition: all var(--transition-fast);
}

.footer-social a:hover {
    background: rgba(59, 130, 246, 0.1);
    color: var(--color-accent);
    transform: translateY(-2px);
}

.footer-col h4 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.footer-links a {
    color: var(--color-text-secondary);
    font-size: 0.9375rem;
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--color-accent);
}

.footer-bottom {
    padding-top: var(--spacing-2xl);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    text-align: center;
    color: var(--color-text-tertiary);
    font-size: 0.875rem;
}

.footer-bottom p {
    margin-bottom: var(--spacing-sm);
}

.footer-bottom a {
    color: var(--color-accent);
}

.footer-bottom a:hover {
    text-decoration: none;
    opacity: 0.8;
}

/* 动画 */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    animation: fadeInUp 0.8s ease-out forwards;
}

.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }
.delay-4 { animation-delay: 0.4s; }

@keyframes fadeInUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    }

    .feature-card.large {
        grid-column: span 1;
    }

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

}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-links.active {
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        display: flex;
        flex-direction: column;
        gap: var(--spacing-md);
        padding: var(--spacing-lg) var(--spacing-xl);
        background: rgba(0, 0, 0, 0.95);
        border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    }

    .nav-links.active .btn-nav {
        width: 100%;
        text-align: center;
    }

    .hero {
        padding: 100px var(--spacing-md) 60px;
    }

    .hero-cta {
        flex-direction: column;
        gap: var(--spacing-md);
    }

    .hero-stats {
        flex-direction: column;
        gap: var(--spacing-lg);
    }

    .stat-divider {
        width: 40px;
        height: 1px;
    }

    .steps-container {
        flex-direction: column;
        gap: var(--spacing-3xl);
    }

    .step-arrow {
        transform: rotate(90deg);
    }

    .cta-buttons {
        flex-direction: column;
    }

    .pricing-table th,
    .pricing-table td {
        padding: var(--spacing-md);
    }

    .plan-cta {
        flex-direction: column;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-2xl);
    }
}

@media (max-width: 480px) {
    html {
        font-size: 14px;
    }

    .section-title {
        font-size: 2rem;
    }

    .section-subtitle {
        font-size: 1rem;
    }
}

.page-header {
    padding: 140px 0 40px;
    background: var(--color-bg);
}

.content-section {
    padding: 60px 0;
    background: var(--color-bg-secondary);
}

.text-block {
    width: 80%;
    max-width: none;
    margin: 0 auto;
    color: var(--color-text-secondary);
    line-height: 1.9;
}


.text-block h2,
.text-block h3 {
    color: var(--color-text-primary);
    margin: var(--spacing-lg) 0 var(--spacing-sm);
}

.text-block p {
    margin-bottom: var(--spacing-md);
}

.text-block ul {
    padding-left: var(--spacing-lg);
    list-style: disc;
}

.card {
    padding: var(--spacing-xl);
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: var(--radius-xl);
}

.card + .card {
    margin-top: var(--spacing-lg);
}