/* 基础样式 */
* {
    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: #f8fafc;
}

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

/* 顶部导航 */
.main-header {
    background: white;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}

.main-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo img {
    height: 40px;
}

.logo h1 {
    font-size: 1.5rem;
    color: #2563eb;
}

.main-nav {
    display: flex;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
    padding: 0.5rem 1rem;
    border-radius: 5px;
}

.nav-link:hover, .nav-link.active {
    background: #2563eb;
    color: white;
}

/* 布局样式 */
.layout-container {
    display: flex;
    min-height: calc(100vh - 80px);
    margin-top: 80px;
}

/* 左侧导航栏 */
.sidebar {
    width: 280px;
    background: #f8fafc;
    border-right: 1px solid #e2e8f0;
    overflow-y: auto;
    position: fixed;
    left: 0;
    top: 80px;
    bottom: 0;
    z-index: 100;
}

.sidebar-content {
    padding: 1rem 1.5rem;
}

/* 折叠菜单样式 */
.sidebar-section {
    margin-bottom: 1rem;
}

.section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    cursor: pointer;
    padding: 0.75rem 0.5rem;
    border-radius: 6px;
    transition: background-color 0.2s;
}

.section-header:hover {
    background: #e2e8f0;
}

.section-header h3 {
    font-size: 0.9rem;
    font-weight: 600;
    color: #64748b;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin: 0;
}

.chevron {
    transition: transform 0.3s ease;
    color: #64748b;
    font-size: 0.8rem;
}

.chevron.down {
    transform: rotate(180deg);
}

.sidebar-menu {
    list-style: none;
    padding: 0;
    margin: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.sidebar-menu.expanded {
    max-height: 500px;
}

.sidebar-link {
    display: block;
    padding: 0.75rem 1rem;
    color: #475569;
    text-decoration: none;
    border-radius: 8px;
    transition: all 0.2s;
    font-size: 0.95rem;
    margin-bottom: 0.25rem;
    cursor: pointer;
}

.sidebar-link:hover {
    background: #e2e8f0;
    color: #1e293b;
}

.sidebar-link.active {
    background: #2563eb;
    color: white;
    font-weight: 500;
}

/* 主内容区域 */
.main-content {
    flex: 1;
    margin-left: 280px;
    padding: 2rem;
    background: white;
}

.content-container {
    max-width: 900px;
    margin: 0 auto;
}

.content-section {
    display: none;
    animation: fadeIn 0.3s ease;
}

.content-section.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* 章节头部 */
.section-header-content {
    margin-bottom: 3rem;
    border-bottom: 1px solid #e2e8f0;
    padding-bottom: 1.5rem;
}

.section-header-content h1 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #1e293b;
    margin-bottom: 0.5rem;
}

.section-subtitle {
    font-size: 1.2rem;
    color: #64748b;
    margin: 0;
}

/* 版本横幅 */
.version-banner {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1.5rem;
    border-radius: 12px;
    margin-bottom: 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.version-info {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.version-tag {
    background: rgba(255,255,255,0.2);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-weight: 600;
}

.update-date {
    font-size: 0.9rem;
    opacity: 0.9;
}

.feature-badges {
    display: flex;
    gap: 0.5rem;
}

.badge {
    background: rgba(255,255,255,0.2);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
}

/* 功能高亮 */
.feature-highlights {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.feature-card {
    background: white;
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    border: 1px solid #e2e8f0;
    text-align: center;
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.feature-card h3 {
    margin-bottom: 0.5rem;
    color: #1e293b;
}

/* 功能详情网格 */
.features-grid {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.feature-detail-card {
    background: #f8fafc;
    padding: 2rem;
    border-radius: 12px;
    border-left: 4px solid #2563eb;
}

.feature-list {
    list-style: none;
    padding: 0;
    margin: 1rem 0 0 0;
}

.feature-list li {
    padding: 0.5rem 0;
    position: relative;
    padding-left: 1.5rem;
}

.feature-list li:before {
    content: "✓";
    color: #10b981;
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* 格式列表 */
.format-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-top: 1rem;
}

.format-category {
    background: white;
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
}

.format-category h4 {
    margin-bottom: 0.5rem;
    color: #2563eb;
    font-size: 0.9rem;
}

/* 系统要求比较 */
.requirements-comparison {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.requirement-tier {
    background: #f8fafc;
    padding: 2rem;
    border-radius: 12px;
    border: 1px solid #e2e8f0;
}

.requirement-tier h3 {
    margin-bottom: 1.5rem;
    color: #1e293b;
}

.specs {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.spec-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 0;
    border-bottom: 1px solid #e2e8f0;
}

.spec-item:last-child {
    border-bottom: none;
}

.spec-label {
    font-weight: 500;
    color: #475569;
}

.spec-value {
    color: #1e293b;
    font-weight: 500;
}

/* 代码块样式 */
.code-block {
    background: #1e293b;
    color: #e2e8f0;
    padding: 1.5rem;
    border-radius: 8px;
    overflow-x: auto;
    margin: 1rem 0;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
    cursor: pointer;
    transition: background-color 0.2s;
}

.code-block:hover {
    background: #374151;
}

.code-block code {
    display: block;
    white-space: pre;
}

/* 提示框样式 */
.tip-box {
    background: #f0f9ff;
    border: 1px solid #bae6fd;
    padding: 1.5rem;
    border-radius: 8px;
    margin: 1.5rem 0;
    border-left: 4px solid #0ea5e9;
}

.warning-box {
    background: #fef2f2;
    border: 1px solid #fecaca;
    padding: 1.5rem;
    border-radius: 8px;
    margin: 1.5rem 0;
    border-left: 4px solid #dc2626;
}

/* 步骤样式 */
.step-guide {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    margin: 2rem 0;
}

.step {
    display: flex;
    gap: 1.5rem;
    align-items: flex-start;
}

.step-number {
    background: #2563eb;
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    flex-shrink: 0;
}

.step-content {
    flex: 1;
}

.step-content h4 {
    margin-bottom: 0.5rem;
    color: #1e293b;
}

/* 应用场景网格 */
.scenarios-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.scenario-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    border: 1px solid #e2e8f0;
}

.scenario-card h4 {
    margin-bottom: 1rem;
    color: #2563eb;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* 页脚 */
.main-footer {
    background: #1e293b;
    color: white;
    padding: 3rem 0;
    margin-top: 4rem;
}

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

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

.footer-section h4 {
    margin-bottom: 1rem;
    color: #cbd5e1;
}

.footer-section a {
    display: block;
    color: #cbd5e1;
    text-decoration: none;
    margin-bottom: 0.5rem;
    transition: color 0.3s;
}

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

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

/* 响应式设计 */
@media (max-width: 768px) {
    .layout-container {
        flex-direction: column;
    }
    
    .sidebar {
        position: static;
        width: 100%;
        height: auto;
    }
    
    .main-content {
        margin-left: 0;
    }
    
    .version-banner {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
    
    .feature-badges {
        justify-content: center;
    }
    
    .step {
        flex-direction: column;
        text-align: center;
    }
}

/* 步骤图片样式 */
.step-image {
    margin-top: 1rem;
    text-align: center;
}

.step-image img {
    max-width: 100%;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    border: 1px solid #e2e8f0;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.step-image img:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 15px rgba(0,0,0,0.15);
}

/* 响应式图片调整 */
@media (max-width: 768px) {
    .step-image img {
        max-width: 95%;
    }
}