/* ========================================
   人妻视频 - 传媒网站样式表
   电影创造服务 | 短视频文案创作
   移动端优先响应式设计
   ======================================== */

/* ========== CSS变量定义 ========== */
:root {
    /* 主色调 */
    --primary-color: #e63946;
    --primary-dark: #c1121f;
    --primary-light: #ff6b6b;
    
    /* 辅助色 */
    --secondary-color: #1d3557;
    --secondary-dark: #14213d;
    --secondary-light: #457b9d;
    
    /* 强调色 */
    --accent-color: #f77f00;
    --accent-dark: #d62828;
    --accent-light: #fcbf49;
    
    /* 中性色 */
    --text-primary: #1a1a2e;
    --text-secondary: #4a4a68;
    --text-muted: #6c6c8a;
    --text-light: #ffffff;
    
    /* 背景色 */
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-dark: #0f0f23;
    --bg-gradient: linear-gradient(135deg, #1d3557 0%, #14213d 100%);
    
    /* 边框和阴影 */
    --border-color: #e9ecef;
    --border-radius: 8px;
    --border-radius-lg: 16px;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.12);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.16);
    
    /* 间距 */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-xxl: 4rem;
    
    /* 字体 */
    --font-primary: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
    --font-heading: "PingFang SC", "Microsoft YaHei", -apple-system, BlinkMacSystemFont, sans-serif;
    
    /* 过渡 */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* 容器宽度 */
    --container-max: 1200px;
    --container-narrow: 800px;
}

/* ========== 重置样式 ========== */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-primary);
    font-size: 1rem;
    line-height: 1.7;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--primary-dark);
}

ul, ol {
    list-style: none;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

address {
    font-style: normal;
}

/* ========== 容器 ========== */
.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-sm);
}

/* ========== 头部导航 ========== */
.site-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: var(--bg-primary);
    box-shadow: var(--shadow-sm);
}

.main-nav {
    padding: var(--spacing-sm) 0;
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-sm);
}

.logo-link {
    display: flex;
    align-items: center;
    flex-shrink: 0;
}

.logo-img {
    height: 40px;
    width: auto;
}

/* 移动端菜单按钮 */
.mobile-menu-toggle {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 44px;
    height: 44px;
    padding: 10px;
    background: transparent;
    border: none;
    cursor: pointer;
    z-index: 1001;
}

.menu-icon {
    position: relative;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition-fast);
}

.menu-icon::before,
.menu-icon::after {
    content: '';
    position: absolute;
    left: 0;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition-fast);
}

.menu-icon::before {
    top: -7px;
}

.menu-icon::after {
    bottom: -7px;
}

.mobile-menu-toggle[aria-expanded="true"] .menu-icon {
    background: transparent;
}

.mobile-menu-toggle[aria-expanded="true"] .menu-icon::before {
    top: 0;
    transform: rotate(45deg);
}

.mobile-menu-toggle[aria-expanded="true"] .menu-icon::after {
    bottom: 0;
    transform: rotate(-45deg);
}

/* 导航菜单 - 移动端 */
.nav-menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 80%;
    max-width: 300px;
    height: 100vh;
    padding: 80px var(--spacing-md) var(--spacing-lg);
    background: var(--bg-primary);
    box-shadow: var(--shadow-lg);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
    transition: right var(--transition-normal);
    overflow-y: auto;
}

.nav-menu.active {
    right: 0;
}

.nav-menu li {
    width: 100%;
}

.nav-link {
    display: block;
    padding: var(--spacing-sm);
    color: var(--text-primary);
    font-weight: 500;
    border-radius: var(--border-radius);
    transition: all var(--transition-fast);
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
    background: rgba(230, 57, 70, 0.08);
}

.nav-link.cta-btn {
    background: var(--primary-color);
    color: var(--text-light);
    text-align: center;
    margin-top: var(--spacing-sm);
}

.nav-link.cta-btn:hover {
    background: var(--primary-dark);
    color: var(--text-light);
}

.nav-link.watch-btn {
    background: var(--accent-color);
    color: var(--text-light);
    text-align: center;
}

.nav-link.watch-btn:hover {
    background: var(--accent-dark);
    color: var(--text-light);
}

/* 移动端菜单遮罩 */
.menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
    z-index: 999;
}

.menu-overlay.active {
    opacity: 1;
    visibility: visible;
}

/* ========== 面包屑导航 ========== */
.breadcrumb {
    background: var(--bg-secondary);
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--border-color);
}

.breadcrumb-list {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 0.875rem;
}

.breadcrumb-item {
    display: flex;
    align-items: center;
}

.breadcrumb-item:not(:last-child)::after {
    content: '/';
    margin-left: var(--spacing-xs);
    color: var(--text-muted);
}

.breadcrumb-item a {
    color: var(--text-secondary);
}

.breadcrumb-item a:hover {
    color: var(--primary-color);
}

.breadcrumb-item.active {
    color: var(--text-primary);
    font-weight: 500;
}

/* ========== 主横幅区域 ========== */
.hero-section {
    position: relative;
    min-height: 60vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-gradient);
    color: var(--text-light);
    text-align: center;
    padding: var(--spacing-xxl) var(--spacing-sm);
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('/images/hero-banner.webp') center/cover no-repeat;
    opacity: 0.3;
    z-index: 0;
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: var(--container-narrow);
}

.hero-title {
    font-family: var(--font-heading);
    font-size: clamp(2rem, 6vw, 3.5rem);
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
    font-size: clamp(1rem, 3vw, 1.25rem);
    opacity: 0.9;
    margin-bottom: var(--spacing-lg);
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-sm);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.875rem 1.75rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: var(--border-radius);
    transition: all var(--transition-fast);
    text-decoration: none;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    color: var(--text-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

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

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

/* ========== 页面标题区域 ========== */
.page-hero {
    background: var(--bg-gradient);
    color: var(--text-light);
    text-align: center;
    padding: var(--spacing-xl) var(--spacing-sm);
}

.page-title {
    font-family: var(--font-heading);
    font-size: clamp(1.75rem, 5vw, 2.5rem);
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.page-subtitle {
    font-size: 1.125rem;
    opacity: 0.9;
}

/* ========== 内容区域 ========== */
.main-content {
    min-height: 50vh;
}

.content-section {
    padding: var(--spacing-xl) 0;
}

.content-section:nth-child(even) {
    background: var(--bg-secondary);
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.section-title {
    font-family: var(--font-heading);
    font-size: clamp(1.5rem, 4vw, 2rem);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
}

/* ========== 文章内容 ========== */
.content-article {
    max-width: var(--container-narrow);
    margin: 0 auto;
}

.content-article h2 {
    font-family: var(--font-heading);
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 3px solid var(--primary-color);
}

.content-article h3 {
    font-family: var(--font-heading);
    font-size: 1.375rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: var(--spacing-lg) 0 var(--spacing-sm);
}

.content-article p {
    margin-bottom: var(--spacing-md);
    text-align: justify;
    text-indent: 2em;
}

.content-image {
    margin: var(--spacing-lg) 0;
}

.content-image img {
    width: 100%;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
}

.content-image figcaption {
    text-align: center;
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-top: var(--spacing-sm);
}

/* ========== 特色卡片 ========== */
.features-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

.feature-card {
    background: var(--bg-primary);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
    text-align: center;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-sm);
}

.feature-card h3 {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.feature-card p {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ========== 服务卡片 ========== */
.services-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

.service-card {
    background: var(--bg-primary);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
}

.service-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.service-image {
    position: relative;
    height: 200px;
    overflow: hidden;
}

.service-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.service-card:hover .service-image img {
    transform: scale(1.05);
}

.service-content {
    padding: var(--spacing-md);
}

.service-content h3 {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.service-content p {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: var(--spacing-sm);
}

.service-link {
    display: inline-flex;
    align-items: center;
    color: var(--primary-color);
    font-weight: 500;
}

.service-link::after {
    content: '→';
    margin-left: 0.5em;
    transition: transform var(--transition-fast);
}

.service-link:hover::after {
    transform: translateX(4px);
}

/* ========== 视频展示 ========== */
.video-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

.video-card {
    background: var(--bg-primary);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
}

.video-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.video-thumbnail {
    position: relative;
    aspect-ratio: 16/9;
    overflow: hidden;
}

.video-thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.play-button {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60px;
    height: 60px;
    background: rgba(230, 57, 70, 0.9);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-light);
    font-size: 1.5rem;
    transition: all var(--transition-fast);
}

.video-card:hover .play-button {
    background: var(--primary-color);
    transform: translate(-50%, -50%) scale(1.1);
}

.video-info {
    padding: var(--spacing-md);
}

.video-info h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.video-meta {
    font-size: 0.875rem;
    color: var(--text-muted);
}

/* ========== 统计数据 ========== */
.stats-section {
    background: var(--bg-gradient);
    color: var(--text-light);
    padding: var(--spacing-xl) 0;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
    text-align: center;
}

.stat-item {
    padding: var(--spacing-md);
}

.stat-number {
    font-family: var(--font-heading);
    font-size: clamp(2rem, 6vw, 3rem);
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.stat-label {
    font-size: 0.9375rem;
    opacity: 0.9;
}

/* ========== 常见问题 ========== */
.faq-list {
    max-width: var(--container-narrow);
    margin: 0 auto;
}

.faq-item {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    box-shadow: var(--shadow-sm);
}

.faq-item h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.faq-item p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ========== APP下载页面 ========== */
.app-showcase {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
    align-items: center;
}

.app-preview {
    max-width: 280px;
}

.app-preview img {
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-lg);
}

.app-info {
    text-align: center;
}

.app-info h2 {
    font-family: var(--font-heading);
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.app-version,
.app-size {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-xs);
}

.app-rating {
    margin: var(--spacing-sm) 0;
}

.app-rating .stars {
    color: var(--accent-color);
    font-size: 1.25rem;
}

.app-rating .rating-text {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-left: var(--spacing-xs);
}

.app-desc {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
    line-height: 1.7;
}

.download-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.download-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius);
    color: var(--text-light);
    transition: all var(--transition-fast);
}

.android-btn {
    background: #3ddc84;
}

.android-btn:hover {
    background: #2bc66a;
    color: var(--text-light);
}

.ios-btn {
    background: #333;
}

.ios-btn:hover {
    background: #000;
    color: var(--text-light);
}

.btn-icon {
    font-size: 1.5rem;
}

.btn-text {
    text-align: left;
}

.btn-text small {
    display: block;
    font-size: 0.75rem;
    opacity: 0.8;
}

.btn-text strong {
    display: block;
    font-size: 1rem;
}

.qr-code-section {
    margin-top: var(--spacing-md);
}

.qr-code-section p {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-sm);
}

.qr-placeholder {
    display: inline-block;
    padding: var(--spacing-sm);
    background: var(--bg-secondary);
    border-radius: var(--border-radius);
}

.qr-placeholder img {
    width: 120px;
    height: 120px;
    object-fit: cover;
}

/* 系统要求 */
.requirements-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

.requirement-card {
    background: var(--bg-primary);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
}

.requirement-card h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    padding-bottom: var(--spacing-xs);
    border-bottom: 2px solid var(--primary-color);
}

.requirement-card ul {
    list-style: disc;
    padding-left: 1.5rem;
}

.requirement-card li {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
}

/* 更新日志 */
.update-log {
    background: var(--bg-primary);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    max-width: var(--container-narrow);
    margin: 0 auto;
}

.update-log h3 {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.update-log ul {
    list-style: disc;
    padding-left: 1.5rem;
}

.update-log li {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
}

/* ========== 页脚 ========== */
.site-footer {
    background: var(--bg-dark);
    color: var(--text-light);
    padding: var(--spacing-xl) 0 var(--spacing-md);
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.footer-brand {
    text-align: center;
}

.footer-logo {
    height: 36px;
    width: auto;
    margin: 0 auto var(--spacing-sm);
}

.footer-desc {
    font-size: 0.875rem;
    opacity: 0.8;
    line-height: 1.6;
}

.footer-nav h3,
.footer-contact h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: var(--text-light);
}

.footer-nav ul {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-sm);
}

.footer-nav a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.875rem;
    transition: color var(--transition-fast);
}

.footer-nav a:hover {
    color: var(--text-light);
}

.footer-contact {
    text-align: center;
}

.footer-contact p {
    font-size: 0.875rem;
    opacity: 0.8;
    margin-bottom: var(--spacing-xs);
}

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-md);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.copyright {
    font-size: 0.8125rem;
    opacity: 0.6;
}

/* ========== 响应式设计 - 平板 ========== */
@media (min-width: 768px) {
    .container {
        padding: 0 var(--spacing-md);
    }
    
    /* 导航 */
    .mobile-menu-toggle {
        display: none;
    }
    
    .nav-menu {
        position: static;
        width: auto;
        max-width: none;
        height: auto;
        padding: 0;
        background: transparent;
        box-shadow: none;
        flex-direction: row;
        gap: var(--spacing-xs);
        overflow: visible;
    }
    
    .nav-menu li {
        width: auto;
    }
    
    .nav-link {
        padding: 0.5rem 0.75rem;
    }
    
    .nav-link.cta-btn {
        margin-top: 0;
        padding: 0.5rem 1rem;
    }
    
    /* 横幅 */
    .hero-section {
        min-height: 70vh;
        padding: var(--spacing-xxl);
    }
    
    /* 特色卡片 */
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    /* 服务卡片 */
    .services-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    /* 视频卡片 */
    .video-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    /* 统计 */
    .stats-grid {
        grid-template-columns: repeat(4, 1fr);
    }
    
    /* APP下载 */
    .app-showcase {
        flex-direction: row;
        text-align: left;
    }
    
    .app-info {
        text-align: left;
        flex: 1;
    }
    
    .download-buttons {
        flex-direction: row;
    }
    
    .requirements-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    /* 页脚 */
    .footer-grid {
        grid-template-columns: 2fr 1fr 1fr;
        text-align: left;
    }
    
    .footer-brand {
        text-align: left;
    }
    
    .footer-logo {
        margin: 0 0 var(--spacing-sm);
    }
    
    .footer-nav ul {
        flex-direction: column;
        justify-content: flex-start;
        gap: var(--spacing-xs);
    }
    
    .footer-contact {
        text-align: left;
    }
}

/* ========== 响应式设计 - 桌面 ========== */
@media (min-width: 1024px) {
    /* 导航 */
    .nav-link {
        padding: 0.5rem 1rem;
    }
    
    /* 横幅 */
    .hero-section {
        min-height: 80vh;
    }
    
    /* 特色卡片 */
    .features-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    /* 服务卡片 */
    .services-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    /* 视频卡片 */
    .video-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* ========== 响应式设计 - 大屏 ========== */
@media (min-width: 1200px) {
    .container {
        padding: 0 var(--spacing-lg);
    }
    
    .features-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* ========== 辅助功能 ========== */
.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* 焦点样式 */
a:focus-visible,
button:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* 减少动画 */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    html {
        scroll-behavior: auto;
    }
}

/* 深色模式支持 */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-primary: #1a1a2e;
        --bg-secondary: #16213e;
        --text-primary: #eaeaea;
        --text-secondary: #b8b8c8;
        --text-muted: #8888a8;
        --border-color: #2a2a4e;
    }
    
    .site-header {
        background: var(--bg-primary);
        border-bottom: 1px solid var(--border-color);
    }
    
    .menu-icon,
    .menu-icon::before,
    .menu-icon::after {
        background: var(--text-primary);
    }
    
    .nav-menu {
        background: var(--bg-primary);
    }
    
    .breadcrumb {
        background: var(--bg-secondary);
        border-bottom-color: var(--border-color);
    }
    
    .feature-card,
    .service-card,
    .video-card,
    .faq-item,
    .requirement-card,
    .update-log {
        background: var(--bg-secondary);
    }
}

/* 打印样式 */
@media print {
    .site-header,
    .site-footer,
    .hero-buttons,
    .download-buttons {
        display: none;
    }
    
    body {
        font-size: 12pt;
        line-height: 1.5;
        color: #000;
        background: #fff;
    }
    
    .container {
        max-width: 100%;
        padding: 0;
    }
    
    a {
        color: #000;
        text-decoration: underline;
    }
    
    img {
        max-width: 100%;
        page-break-inside: avoid;
    }
}