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

/* 基础样式 */
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
    overflow-x: hidden;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 主内容区域 */
#main-content {
    display: block;
    transition: opacity 0.5s ease;
}

/* 头部样式 */
header {
    background-color: #2c3e50;
    color: #fff;
    padding: 20px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.logo {
    text-align: center;
}

.logo h1 {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 5px;
}

.logo p {
    font-size: 14px;
    color: #ecf0f1;
    opacity: 0.9;
}

/* 英雄区域 */
.hero {
    background: linear-gradient(135deg, #3498db, #2c3e50);
    color: #fff;
    padding: 120px 0 80px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at center, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
}

.hero h2 {
    font-size: 64px;
    margin-bottom: 10px;
    font-weight: 900;
    letter-spacing: -2px;
    text-transform: uppercase;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.hero h3 {
    font-size: 24px;
    margin-bottom: 30px;
    font-weight: 300;
    opacity: 0.9;
}

.hero p {
    font-size: 20px;
    margin-bottom: 50px;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    opacity: 0.95;
}

.download-section {
    margin-top: 40px;
}

.btn {
    display: inline-block;
    padding: 15px 40px;
    background-color: #e74c3c;
    color: #fff;
    text-decoration: none;
    font-size: 18px;
    font-weight: 600;
    border-radius: 50px;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 1px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.btn:hover {
    background-color: #c0392b;
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
}

.download-btn {
    font-size: 20px;
    padding: 20px 50px;
}

/* 功能区域 */
.features {
    padding: 100px 0;
    background-color: #fff;
}

.features h2 {
    text-align: center;
    font-size: 36px;
    margin-bottom: 60px;
    color: #2c3e50;
    position: relative;
}

.features h2::after {
    content: '';
    display: block;
    width: 80px;
    height: 4px;
    background: linear-gradient(to right, #3498db, #2c3e50);
    margin: 20px auto 0;
    border-radius: 2px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 40px;
}

.feature-item {
    background-color: #f8f9fa;
    padding: 40px 30px;
    border-radius: 10px;
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid #e9ecef;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

.feature-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
    border-color: #3498db;
}

.feature-item h3 {
    font-size: 22px;
    margin-bottom: 15px;
    color: #2c3e50;
}

.feature-item p {
    color: #7f8c8d;
    font-size: 16px;
    line-height: 1.6;
}

/* 下载区域 */
.download {
    padding: 100px 0;
    background-color: #f8f9fa;
    text-align: center;
}

.download h2 {
    font-size: 36px;
    margin-bottom: 60px;
    color: #2c3e50;
    position: relative;
}

.download h2::after {
    content: '';
    display: block;
    width: 80px;
    height: 4px;
    background: linear-gradient(to right, #3498db, #2c3e50);
    margin: 20px auto 0;
    border-radius: 2px;
}

.download-options {
    display: flex;
    justify-content: center;
    gap: 60px;
    flex-wrap: wrap;
}

.download-item {
    background-color: #fff;
    padding: 40px;
    border-radius: 10px;
    width: 100%;
    max-width: 300px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
}

.download-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
}

.download-item h3 {
    font-size: 24px;
    margin-bottom: 20px;
    color: #2c3e50;
}

.download-item p {
    color: #7f8c8d;
    margin-bottom: 30px;
    font-size: 16px;
}

.download-item ul {
    list-style: none;
    text-align: left;
    margin-bottom: 20px;
}

.download-item li {
    color: #7f8c8d;
    margin-bottom: 10px;
    padding-left: 20px;
    position: relative;
}

.download-item li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: #27ae60;
    font-weight: bold;
}

/* 使用方法区域 */
.usage {
    padding: 100px 0;
    background-color: #fff;
}

.usage h2 {
    text-align: center;
    font-size: 36px;
    margin-bottom: 60px;
    color: #2c3e50;
    position: relative;
}

.usage h2::after {
    content: '';
    display: block;
    width: 80px;
    height: 4px;
    background: linear-gradient(to right, #3498db, #2c3e50);
    margin: 20px auto 0;
    border-radius: 2px;
}

.usage-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    max-width: 900px;
    margin: 0 auto;
}

.step {
    background-color: #f8f9fa;
    padding: 30px;
    border-radius: 10px;
    text-align: center;
    position: relative;
    border: 1px solid #e9ecef;
}

.step::before {
    content: attr(data-step);
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%);
    background-color: #3498db;
    color: #fff;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: bold;
    font-size: 16px;
}

.step h3 {
    font-size: 22px;
    margin-bottom: 15px;
    color: #2c3e50;
}

.step p {
    color: #7f8c8d;
    font-size: 16px;
}

.step code {
    background-color: #2c3e50;
    color: #ecf0f1;
    padding: 3px 8px;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 14px;
}

/* 页脚样式 */
footer {
    background-color: #2c3e50;
    color: #ecf0f1;
    padding: 40px 0;
    text-align: center;
}

footer p {
    margin: 10px 0;
    font-size: 14px;
    opacity: 0.8;
}

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

/* 响应式设计 */
@media (max-width: 768px) {
    .hero h2 {
        font-size: 48px;
    }
    
    .hero h3 {
        font-size: 20px;
    }
    
    .hero p {
        font-size: 18px;
    }
    
    .download-btn {
        font-size: 18px;
        padding: 18px 40px;
    }
    
    .features-grid,
    .usage-steps {
        grid-template-columns: 1fr;
    }
    
    .download-options {
        gap: 30px;
    }
    
    .features h2,
    .download h2,
    .usage h2 {
        font-size: 30px;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 80px 0 60px;
    }
    
    .hero h2 {
        font-size: 36px;
    }
    
    .hero h3 {
        font-size: 18px;
    }
    
    .hero p {
        font-size: 16px;
    }
    
    .download-btn {
        font-size: 16px;
        padding: 15px 30px;
    }
    
    .modal-content {
        padding: 30px 20px;
    }
    
    .modal-content h2 {
        font-size: 24px;
    }
    
    .feature-item,
    .download-item,
    .step {
        padding: 25px 20px;
    }
    
    .features h2,
    .download h2,
    .usage h2 {
        font-size: 28px;
    }
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

/* 加载动画 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid #f3f3f3;
    border-top: 3px solid #3498db;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}