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

:root {
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --accent-color: #3b82f6;
    --text-color: #1f2937;
    --light-bg: #f8fafc;
    --white: #ffffff;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    overflow-x: hidden;
}

/* 头部样式 */
.header {
    background: var(--white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

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

.logo a {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: var(--primary-color);
    font-size: 1.5rem;
    font-weight: bold;
}

.logo h1 {
    margin-right: 0.5rem;
}

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

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

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

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition);
}

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

.download-btn {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    cursor: pointer;
    font-weight: 600;
    transition: var(--transition);
}

.download-btn:hover {
    background: var(--secondary-color);
    transform: translateY(-2px);
}

/* 英雄区域 */
.hero {
    max-width: 1200px;
    margin: 0 auto;
    padding: 4rem 2rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    min-height: 80vh;
}

.hero-title {
    font-size: 3rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: 1.5rem;
    color: #4b5563;
    margin-bottom: 1.5rem;
}

.hero-description {
    font-size: 1.1rem;
    line-height: 1.8;
    color: #6b7280;
    margin-bottom: 2rem;
}

.cta-buttons {
    display: flex;
    gap: 1rem;
    margin-bottom: 3rem;
}

.primary-btn, .secondary-btn {
    padding: 1rem 2rem;
    border-radius: 0.5rem;
    font-weight: 600;
    font-size: 1.1rem;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    display: flex;
    flex-direction: column;
    align-items: center;
}

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

.primary-btn:hover {
    background: var(--secondary-color);
    transform: translateY(-2px);
}

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

.secondary-btn:hover {
    background: var(--light-bg);
}

.stats {
    display: flex;
    gap: 3rem;
}

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

.stat-number {
    font-size: 2rem;
    font-weight: 800;
    color: var(--primary-color);
}

.stat-label {
    font-size: 0.9rem;
    color: #6b7280;
}

.hero-image img {
    width: 100%;
    height: auto;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.hero-image img:hover {
    transform: translateY(-5px);
}

/* 特性区域 */
.features {
    background: var(--light-bg);
    padding: 5rem 2rem;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 3rem;
    color: var(--text-color);
}

.features-grid {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-10px);
}

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

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

/* 下载区域 */
.download {
    padding: 5rem 2rem;
}

.download-platforms {
    max-width: 1200px;
    margin: 0 auto 3rem;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.platform-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: var(--shadow);
    text-align: center;
    transition: var(--transition);
}

.platform-card:hover {
    transform: scale(1.05);
}

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

.platform-card h3 {
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

.platform-card p {
    color: #6b7280;
    margin-bottom: 1.5rem;
}

.download-instructions {
    max-width: 800px;
    margin: 0 auto;
    background: var(--light-bg);
    padding: 2rem;
    border-radius: 1rem;
}

.download-instructions ol {
    margin-top: 1rem;
    padding-left: 1.5rem;
}

.download-instructions li {
    margin-bottom: 0.5rem;
    color: #4b5563;
}

/* FAQ区域 */
.faq {
    padding: 5rem 2rem;
    background: var(--white);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    margin-bottom: 1rem;
    border: 1px solid #e5e7eb;
    border-radius: 0.5rem;
    overflow: hidden;
}

.faq-question {
    width: 100%;
    padding: 1.5rem;
    background: var(--light-bg);
    border: none;
    text-align: left;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
}

.faq-question:hover {
    background: #e5e7eb;
}

.faq-question::after {
    content: '+';
    font-size: 1.5rem;
    transition: var(--transition);
}

.faq-question.active::after {
    content: '-';
}

.faq-answer {
    padding: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-answer.active {
    padding: 1.5rem;
    max-height: 500px;
}

/* 页脚 */
.footer {
    background: #1f2937;
    color: white;
    padding: 3rem 2rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: white;
}

.footer-section p,
.footer-section a {
    color: #d1d5db;
    margin-bottom: 0.5rem;
    text-decoration: none;
    transition: var(--transition);
}

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

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

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

.footer-bottom {
    max-width: 1200px;
    margin: 2rem auto 0;
    padding-top: 2rem;
    border-top: 1px solid #374151;
    text-align: center;
    color: #9ca3af;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        padding: 2rem 1rem;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .stats {
        flex-direction: column;
        gap: 1.5rem;
    }
    
    .cta-buttons {
        flex-direction: column;
    }
    
    .features-grid,
    .download-platforms {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .nav-container {
        padding: 1rem;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
}

/* 打印样式 */
@media print {
    .header, .footer, .download-btn, .cta-buttons {
        display: none;
    }
    
    body {
        color: black;
    }
}

/* 深色模式支持 */
@media (prefers-color-scheme: dark) {
    body {
        background: #1a1a1a;
        color: #e5e5e5;
    }
    
    .feature-card,
    .platform-card {
        background: #2d2d2d;
        color: #e5e5e5;
    }
}