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

/* 基础样式 */
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Topbar样式 */
.topbar {
    background: #1a1a1a;
    color: #fff;
    padding: 12px 0;
    font-size: 14px;
    line-height: 1.5;
}

.topbar-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.topbar-text {
    color: #fff;
}

.topbar-actions {
    display: flex;
    gap: 15px;
}

.btn-login,
.btn-register {
    color: #fff;
    text-decoration: none;
    padding: 8px 20px;
    border-radius: 4px;
    transition: background-color 0.3s;
}

.btn-login {
    background: transparent;
    border: 1px solid #fff;
}

.btn-login:hover {
    background: rgba(255, 255, 255, 0.1);
}

.btn-register {
    background: #007bff;
    border: none;
}

.btn-register:hover {
    background: #0056b3;
}

/* 主导航样式 */
.main-header {
    background: #fff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.main-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 18px 0;
    gap: 20px;
}

.logo img {
    height: 50px;
    width: auto;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 8px;
    align-items: center;
    margin: 0;
    padding: 0;
}

.nav-menu > li {
    position: relative;
}

.nav-menu a {
    color: #333;
    text-decoration: none;
    font-weight: 500;
    padding: 12px 16px;
    display: block;
    transition: color 0.3s, background-color 0.3s;
    font-size: 15px;
    line-height: 1.4;
    touch-action: manipulation;
    -webkit-tap-highlight-color: transparent;
    border-radius: 4px;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: #007bff;
}

.nav-menu .arrow {
    font-size: 10px;
    margin-left: 5px;
}

/* 下拉菜单 */
.dropdown-menu {
    display: none !important;
    position: absolute;
    top: 100%;
    left: 0;
    background: #fff;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    list-style: none;
    min-width: 200px;
    padding: 10px 0;
    z-index: 1000;
}

.dropdown:hover .dropdown-menu {
    display: block !important;
}

.dropdown:hover .dropdown-menu.multi-column {
    display: grid !important;
}

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

.dropdown-menu a {
    padding: 10px 20px;
    display: block;
    color: #333;
    text-decoration: none;
    transition: background-color 0.3s;
}

.dropdown-menu a:hover {
    background-color: #f5f5f5;
}

.dropdown-menu.multi-column {
    grid-template-columns: repeat(3, 1fr);
    min-width: 600px;
    display: none !important;
}

/* 面包屑导航 */
.breadcrumb {
    background: #fff;
    padding: 15px 0;
    border-bottom: 1px solid #e0e0e0;
}

.breadcrumb ol {
    display: flex;
    list-style: none;
    gap: 10px;
    align-items: center;
}

.breadcrumb a {
    color: #007bff;
    text-decoration: none;
}

.breadcrumb a:hover {
    text-decoration: underline;
}

/* 英雄区域 */
.hero-section {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    padding: 80px 0 100px;
    text-align: center;
}

.hero-section h1 {
    font-size: 2.75em;
    margin-bottom: 24px;
    font-weight: 700;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

.hero-subtitle {
    font-size: 1.25em;
    margin-bottom: 36px;
    opacity: 0.95;
    line-height: 1.6;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.hero-actions {
    display: flex;
    gap: 20px;
    justify-content: center;
}

.btn-primary,
.btn-secondary {
    padding: 15px 30px;
    border-radius: 5px;
    text-decoration: none;
    font-weight: bold;
    transition: transform 0.3s, box-shadow 0.3s;
    display: inline-block;
}

.btn-primary {
    background: #fff;
    color: #667eea;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

.btn-secondary {
    background: transparent;
    color: #fff;
    border: 2px solid #fff;
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
}

/* 分类区域 */
.categories-section {
    padding: 80px 0;
    background: #fff;
}

.categories-section h2 {
    text-align: center;
    font-size: 2.5em;
    margin-bottom: 50px;
    color: #333;
    font-weight: 700;
    line-height: 1.2;
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 32px;
}

.category-card {
    background: #fff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    transition: transform 0.3s, box-shadow 0.3s;
}

.category-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 8px 24px rgba(0,0,0,0.12);
}

.category-card img {
    width: 100%;
    height: 220px;
    object-fit: cover;
    display: block;
}

.category-card h3 {
    padding: 24px 24px 12px;
    font-size: 1.4em;
    color: #333;
    font-weight: 600;
    line-height: 1.3;
    margin: 0;
}

.category-card p {
    padding: 0 24px 20px;
    color: #666;
    font-size: 15px;
    line-height: 1.6;
    margin: 0;
}

.category-card .btn-link {
    display: block;
    padding: 16px 24px;
    background: #f8f9fa;
    color: #007bff;
    text-decoration: none;
    text-align: center;
    transition: background-color 0.3s, color 0.3s;
    font-weight: 500;
    font-size: 15px;
    border-top: 1px solid #f0f0f0;
}

.category-card .btn-link:hover {
    background: #e9ecef;
    color: #0056b3;
}

/* 关于我们区域 */
.about-section {
    padding: 80px 0;
    background: #f9f9f9;
}

.about-section h2 {
    text-align: center;
    font-size: 2.5em;
    margin-bottom: 48px;
    color: #333;
    font-weight: 700;
    line-height: 1.2;
}

.about-content {
    max-width: 840px;
    margin: 0 auto;
}

.about-content p {
    font-size: 16px;
    line-height: 1.75;
    margin-bottom: 24px;
    color: #555;
}

.about-content h3 {
    font-size: 1.5em;
    margin: 36px 0 20px;
    color: #333;
    font-weight: 600;
    line-height: 1.3;
}

.about-content ul {
    list-style: none;
    padding-left: 0;
    margin: 0;
}

.about-content li {
    padding: 12px 0;
    font-size: 16px;
    color: #555;
    line-height: 1.6;
}

/* FAQ区域 */
.faq-section {
    padding: 80px 0;
    background: #fff;
}

.faq-section h2 {
    text-align: center;
    font-size: 2.5em;
    margin-bottom: 48px;
    color: #333;
    font-weight: 700;
    line-height: 1.2;
}

.faq-list {
    max-width: 840px;
    margin: 0 auto;
}

.faq-item {
    background: #f9f9f9;
    border-radius: 10px;
    padding: 28px 32px;
    margin-bottom: 24px;
    transition: box-shadow 0.3s;
}

.faq-item:hover {
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.faq-item h3 {
    font-size: 1.25em;
    margin-bottom: 12px;
    color: #333;
    font-weight: 600;
    line-height: 1.4;
}

.faq-item p {
    color: #555;
    line-height: 1.7;
    font-size: 15px;
    margin: 0;
}

/* 内容区域 */
.content-section {
    padding: 60px 0;
    background: #fff;
    margin-bottom: 0;
}

.content-section h2 {
    font-size: 2em;
    margin-bottom: 28px;
    color: #333;
    font-weight: 700;
    line-height: 1.3;
}

.content-section p {
    font-size: 16px;
    line-height: 1.75;
    color: #555;
    margin-bottom: 24px;
}

.content-section ul {
    list-style: none;
    padding-left: 0;
}

.content-section li {
    padding: 10px 0;
    font-size: 1.1em;
    color: #666;
}

/* 产品网格 */
.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.product-card {
    background: #f9f9f9;
    border-radius: 8px;
    padding: 25px;
    transition: transform 0.3s, box-shadow 0.3s;
}

.product-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.product-card h3 {
    font-size: 1.3em;
    margin-bottom: 15px;
    color: #333;
}

.product-card p {
    color: #666;
    margin-bottom: 15px;
    line-height: 1.6;
}

.btn-link {
    color: #007bff;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
    display: inline-block;
    min-height: 44px;
    line-height: 44px;
    touch-action: manipulation;
    -webkit-tap-highlight-color: transparent;
}

.btn-link:hover {
    color: #0056b3;
    text-decoration: underline;
}

/* 特性列表 */
.features-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
    margin-top: 30px;
}

.feature-item {
    background: #f9f9f9;
    border-radius: 8px;
    padding: 25px;
}

.feature-item h3 {
    font-size: 1.3em;
    margin-bottom: 15px;
    color: #333;
}

.feature-item p {
    color: #666;
    line-height: 1.6;
}

/* CTA区域 */
.cta-section {
    text-align: center;
    padding: 60px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    margin-top: 40px;
}

.cta-section h2 {
    font-size: 2.5em;
    margin-bottom: 20px;
    color: #fff;
}

.cta-section p {
    font-size: 1.2em;
    margin-bottom: 30px;
    opacity: 0.9;
}

/* 页脚 */
.main-footer {
    background: #1a1a1a;
    color: #fff;
    padding: 60px 0 20px;
    margin-top: 60px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h3 {
    font-size: 1.3em;
    margin-bottom: 20px;
    color: #fff;
}

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

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section a {
    color: #ccc;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-section a:hover {
    color: #fff;
}

.footer-section p {
    color: #ccc;
    line-height: 1.8;
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #333;
    color: #ccc;
}

/* 文章样式 */
article h1 {
    font-size: 2.5em;
    margin: 40px 0 20px;
    color: #333;
}

/* 移动端菜单按钮 */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-around;
    width: 44px;
    height: 44px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1001;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background: #333;
    border-radius: 3px;
    transition: all 0.3s;
}

.mobile-menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(8px, 8px);
}

.mobile-menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 0 20px;
    }
    
    .topbar {
        padding: 10px 0;
        font-size: 13px;
    }
    
    .topbar-content {
        flex-direction: column;
        gap: 12px;
    }
    
    .topbar-actions {
        flex-direction: row;
        width: 100%;
        gap: 12px;
        justify-content: center;
    }
    
    .btn-login,
    .btn-register {
        flex: 1;
        max-width: 200px;
        text-align: center;
        padding: 10px 18px;
        font-size: 15px;
    }
    
    .main-nav {
        flex-wrap: wrap;
        position: relative;
        padding: 16px 0;
        gap: 16px;
    }
    
    .logo img {
        height: 45px;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .nav-menu {
        display: none;
        flex-direction: column;
        gap: 0;
        width: 100%;
        margin-top: 12px;
        background: #fff;
        border-top: 1px solid #e0e0e0;
        padding-top: 12px;
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .nav-menu > li {
        width: 100%;
        border-bottom: 1px solid #f0f0f0;
    }
    
    .nav-menu a {
        padding: 14px 20px;
        font-size: 15px;
        display: block;
        min-height: 44px;
        line-height: 1.5;
    }
    
    .dropdown-menu {
        position: static;
        display: none !important;
        width: 100%;
        box-shadow: none;
        background: #f9f9f9;
        padding: 0;
    }
    
    .dropdown.active .dropdown-menu {
        display: block !important;
    }
    
    .dropdown-menu.multi-column {
        grid-template-columns: 1fr;
        min-width: 100%;
        display: none !important;
    }
    
    .dropdown.active .dropdown-menu.multi-column {
        display: grid !important;
    }
    
    .dropdown-menu li {
        border-bottom: 1px solid #e0e0e0;
    }
    
    .dropdown-menu a {
        padding: 15px 30px;
        font-size: 15px;
        min-height: 44px;
        line-height: 44px;
    }
    
    .hero-section {
        padding: 50px 0;
    }
    
    .hero-section h1 {
        font-size: 2em;
        padding: 0 10px;
    }
    
    .hero-subtitle {
        font-size: 1.1em;
        padding: 0 10px;
    }
    
    .hero-actions {
        flex-direction: column;
        align-items: center;
        gap: 15px;
        padding: 0 20px;
    }
    
    .btn-primary,
    .btn-secondary {
        width: 100%;
        max-width: 300px;
        padding: 15px 30px;
        font-size: 16px;
        text-align: center;
        min-height: 44px;
    }
    
    .categories-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .category-card img {
        height: 180px;
    }
    
    .category-card h3 {
        font-size: 1.3em;
        padding: 15px 15px 10px;
    }
    
    .category-card p {
        padding: 0 15px 15px;
        font-size: 14px;
    }
    
    .category-card .btn-link {
        padding: 12px 15px;
        font-size: 15px;
        min-height: 44px;
    }
    
    .products-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .product-card {
        padding: 20px;
    }
    
    .product-card h3 {
        font-size: 1.3em;
        margin-bottom: 10px;
    }
    
    .product-card p {
        font-size: 14px;
        margin-bottom: 15px;
    }
    
    .product-card .btn-link {
        padding: 12px 20px;
        font-size: 15px;
        min-height: 44px;
    }
    
    .features-list {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .content-section {
        padding: 30px 0;
    }
    
    .content-section h2 {
        font-size: 1.8em;
        margin-bottom: 20px;
        padding: 0 10px;
    }
    
    .content-section p {
        font-size: 16px;
        line-height: 1.8;
        padding: 0 10px;
    }
    
    article h1 {
        font-size: 1.8em;
        padding: 0 10px;
    }
    
    .btn-link {
        min-height: 44px;
        line-height: 44px;
        padding: 0 20px;
        font-size: 15px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .topbar {
        padding: 8px 0;
        font-size: 12px;
    }
    
    .topbar-text {
        font-size: 12px;
    }
    
    .logo img {
        height: 40px;
    }
    
    .hero-section {
        padding: 40px 0;
    }
    
    .hero-section h1 {
        font-size: 1.6em;
        line-height: 1.3;
    }
    
    .hero-subtitle {
        font-size: 1em;
    }
    
    .categories-section,
    .about-section,
    .faq-section {
        padding: 40px 0;
    }
    
    .categories-section h2,
    .about-section h2,
    .faq-section h2 {
        font-size: 1.6em;
    }
    
    .category-card h3,
    .product-card h3 {
        font-size: 1.2em;
    }
    
    .content-section h2 {
        font-size: 1.5em;
    }
    
    article h1 {
        font-size: 1.6em;
    }
    
    .btn-primary,
    .btn-secondary {
        padding: 12px 25px;
        font-size: 15px;
    }
    
    .main-footer {
        padding: 30px 0;
    }
    
    .footer-section h3 {
        font-size: 1.2em;
    }
    
    .footer-section p,
    .footer-section li {
        font-size: 14px;
    }
}