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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

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

/* 顶部导航栏 */
.header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
}

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

.logo-section {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.back-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: #f8f9fa;
    color: #495057;
    text-decoration: none;
    border-radius: 6px;
    transition: all 0.3s ease;
    font-size: 0.9rem;
}

.back-btn:hover {
    background: #e9ecef;
    transform: translateY(-1px);
}

.header h1 {
    color: #2c3e50;
    font-size: 1.8rem;
    font-weight: 600;
}

.header h1 i {
    color: #e74c3c;
    margin-right: 0.5rem;
}

.header-info {
    color: #6c757d;
    font-style: italic;
}

/* 英雄区域 */
.hero {
    padding: 4rem 0;
    color: white;
    position: relative;
    overflow: hidden;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.hero-content h2 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.hero-stats {
    display: flex;
    gap: 2rem;
    margin-top: 2rem;
}

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

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: #ffd700;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 0.9rem;
    opacity: 0.8;
}

/* 分子动画 */
.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
}

.molecule-animation {
    position: relative;
    width: 300px;
    height: 300px;
    animation: rotate 20s linear infinite;
}

.atom {
    position: absolute;
    border-radius: 50%;
    box-shadow: 0 4px 20px rgba(255, 255, 255, 0.3);
}

.atom-1 {
    width: 60px;
    height: 60px;
    background: linear-gradient(45deg, #ff6b6b, #ee5a52);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation: pulse 2s ease-in-out infinite;
}

.atom-2 {
    width: 40px;
    height: 40px;
    background: linear-gradient(45deg, #4ecdc4, #44a08d);
    top: 20%;
    left: 30%;
    animation: pulse 2s ease-in-out infinite 0.5s;
}

.atom-3 {
    width: 40px;
    height: 40px;
    background: linear-gradient(45deg, #45b7d1, #96c93d);
    bottom: 20%;
    right: 30%;
    animation: pulse 2s ease-in-out infinite 1s;
}

.bond {
    position: absolute;
    background: rgba(255, 255, 255, 0.6);
    border-radius: 2px;
}

.bond-1 {
    width: 4px;
    height: 100px;
    top: 35%;
    left: 48%;
    transform: rotate(45deg);
}

.bond-2 {
    width: 4px;
    height: 100px;
    top: 45%;
    right: 45%;
    transform: rotate(-45deg);
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

@keyframes pulse {
    0%, 100% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.1); opacity: 0.8; }
}

/* 模块展示区域 */
.modules-section {
    padding: 4rem 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    color: #2c3e50;
    margin-bottom: 1rem;
    font-weight: 700;
}

.section-description {
    text-align: center;
    font-size: 1.1rem;
    color: #6c757d;
    margin-bottom: 3rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.modules-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.module-card {
    background: white;
    border-radius: 16px;
    padding: 2rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.module-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.15);
}

.module-card.available {
    border-left: 5px solid #28a745;
}

.module-card.coming-soon {
    border-left: 5px solid #ffc107;
    opacity: 0.8;
}

.module-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
}

.module-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(45deg, #667eea, #764ba2);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.8rem;
}

.module-status {
    padding: 0.3rem 0.8rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
}

.module-status.available {
    background: #d4edda;
    color: #155724;
}

.module-status.coming-soon {
    background: #fff3cd;
    color: #856404;
}

.module-content h3 {
    font-size: 1.5rem;
    color: #2c3e50;
    margin-bottom: 1rem;
    font-weight: 600;
}

.module-content p {
    color: #6c757d;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.module-features {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.feature-tag {
    background: #f8f9fa;
    color: #495057;
    padding: 0.3rem 0.8rem;
    border-radius: 15px;
    font-size: 0.8rem;
    font-weight: 500;
}

.module-stats {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.stat {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: #6c757d;
    font-size: 0.9rem;
}

.stat i {
    color: #667eea;
}

.module-footer {
    margin-top: 2rem;
}

.module-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.8rem;
    padding: 1rem 1.5rem;
    border: none;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    cursor: pointer;
    width: 100%;
    justify-content: center;
}

.module-btn.available {
    background: linear-gradient(45deg, #28a745, #20c997);
    color: white;
}

.module-btn.available:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(40, 167, 69, 0.4);
}

.module-btn.coming-soon {
    background: #f8f9fa;
    color: #6c757d;
    cursor: not-allowed;
}

/* 功能特色区域 */
.features-section {
    padding: 4rem 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.feature-item {
    text-align: center;
    padding: 2rem 1rem;
}

.feature-icon {
    width: 80px;
    height: 80px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    margin: 0 auto 1.5rem;
    backdrop-filter: blur(10px);
}

.feature-item h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    font-weight: 600;
}

.feature-item p {
    opacity: 0.9;
    line-height: 1.6;
}

/* 使用指南区域 */
.guide-section {
    padding: 4rem 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
}

.guide-steps {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-top: 3rem;
    flex-wrap: wrap;
}

.step-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    background: white;
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    max-width: 200px;
    text-align: center;
}

.step-number {
    width: 40px;
    height: 40px;
    background: linear-gradient(45deg, #667eea, #764ba2);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.2rem;
    flex-shrink: 0;
}

.step-content h3 {
    color: #2c3e50;
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.step-content p {
    color: #6c757d;
    font-size: 0.9rem;
    line-height: 1.4;
}

.step-arrow {
    color: #667eea;
    font-size: 1.5rem;
}

/* 底部信息 */
.footer {
    background: #2c3e50;
    color: white;
    padding: 3rem 0 1rem;
}

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

.footer-info h3 {
    margin-bottom: 1rem;
    color: #ecf0f1;
}

.footer-info p {
    opacity: 0.8;
    line-height: 1.6;
}

.footer-links h4 {
    margin-bottom: 1rem;
    color: #ecf0f1;
}

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

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

.footer-links a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: #ecf0f1;
}

.footer-contact h4 {
    margin-bottom: 1rem;
    color: #ecf0f1;
}

.footer-contact p {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
    opacity: 0.8;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #34495e;
    opacity: 0.7;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-content h2 {
        font-size: 2rem;
    }
    
    .modules-grid {
        grid-template-columns: 1fr;
    }
    
    .guide-steps {
        flex-direction: column;
    }
    
    .step-arrow {
        transform: rotate(90deg);
    }
    
    .step-item {
        max-width: 100%;
        flex-direction: column;
        text-align: center;
    }
    
    .container {
        padding: 0 1rem;
    }
    
    .header-content {
        padding: 0 1rem;
        flex-direction: column;
        gap: 1rem;
    }
}

@media (max-width: 480px) {
    .hero-stats {
        flex-direction: column;
        gap: 1rem;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .module-card {
        padding: 1.5rem;
    }
}