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

:root {
    --primary-color: #6366f1;
    --secondary-color: #8b5cf6;
    --dark-bg: #0f172a;
    --light-bg: #f8fafc;
    --text-dark: #1e293b;
    --text-light: #64748b;
    --white: #ffffff;
    --gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.15);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--white);
}

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    z-index: 1000;
    transition: all 0.3s ease;
}

.navbar.scrolled {
    box-shadow: var(--shadow);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

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

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

.nav-links a.active {
    color: var(--primary-color);
}

.btn {
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
    display: inline-block;
}

.btn-primary {
    background: var(--gradient);
    color: var(--white);
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
}

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

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

/* Hero Section */
.hero {
    margin-top: 80px;
    padding: 6rem 2rem;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: var(--white);
    text-align: center;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

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

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

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.1rem;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 4rem 2rem;
}

/* 特性卡片 */
.features {
    background-color: var(--light-bg);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.section-subtitle {
    text-align: center;
    font-size: 1.1rem;
    color: var(--text-light);
    margin-bottom: 3rem;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

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

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

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

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

.feature-card p {
    color: var(--text-light);
    line-height: 1.8;
}

/* 价格卡片 */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.pricing-card {
    background: var(--white);
    border-radius: 12px;
    padding: 2.5rem;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    text-align: center;
    border: 2px solid transparent;
}

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

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

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

.price {
    font-size: 3rem;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin: 1rem 0;
}

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

.features-list {
    list-style: none;
    margin: 2rem 0;
    text-align: left;
}

.features-list li {
    padding: 0.75rem 0;
    color: var(--text-light);
    border-bottom: 1px solid #e2e8f0;
}

.features-list li:before {
    content: "✓ ";
    color: var(--primary-color);
    font-weight: bold;
    margin-right: 0.5rem;
}

/* CTA Section */
.cta {
    background: var(--gradient);
    color: var(--white);
    text-align: center;
    padding: 5rem 2rem;
}

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

.cta p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.95;
}

/* Footer */
.footer {
    background-color: var(--dark-bg);
    color: var(--white);
    padding: 3rem 2rem 1rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3 {
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

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

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section a:hover {
    color: var(--white);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.6);
}

/* 联系表单 */
.contact-form {
    max-width: 600px;
    margin: 0 auto;
    background: var(--white);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-dark);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid #e2e8f0;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group textarea {
    resize: vertical;
    min-height: 150px;
}

/* 响应式设计 */
.mobile-menu-toggle {
    display: none;
    font-size: 1.5rem;
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-dark);
}

@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: block;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background-color: var(--white);
        flex-direction: column;
        padding: 1rem;
        box-shadow: var(--shadow);
    }

    .nav-links.active {
        display: flex;
    }

    .hero h1 {
        font-size: 2.5rem;
    }

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

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

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

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

/* 动画效果 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.6s ease-out;
}

/* 滚动动画 */
.scroll-reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.scroll-reveal.active {
    opacity: 1;
    transform: translateY(0);
}