/* 基础样式 - 优化版 */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        :root {
            --primary-color: #4361ee;
            --secondary-color: #3a0ca3;
            --accent-color: #4cc9f0;
            --dark-color: #2b2d42;
            --light-color: #f8f9fa;
            --sidebar-bg: #333;
            --card-bg: #ffffff;
            --footer-bg: #f8f9fa;
            --border-radius: 12px;
            --shadow: 0 10px 20px rgba(0, 0, 0, 0.08);
            --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
            --gradient: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
        }

        body {
            font-family: 'Segoe UI', 'SF Pro Display', -apple-system, BlinkMacSystemFont, sans-serif;
            background: linear-gradient(135deg, #f5f7fa 0%, #e4edf5 100%);
            color: var(--dark-color);
            line-height: 1.7;
            min-height: 100vh;
        }

        /* 布局优化 */
        .layout {
            display: flex;
            min-height: 100vh;
        }

        /* 侧边栏 - 优化 */
        .sidebar {
            width: 100px;
            background: #eaeaea(--sidebar-bg);
            color: white;
            display: flex;
            flex-direction: column;
            align-items: center;
            padding: 25px 0;
            transition: var(--transition);
            z-index: 100;
            box-shadow: 5px 0 15px rgba(0, 0, 0, 0.1);
            position: relative;
        }

        .sidebar-header {
            margin-bottom: 40px;
            display: flex;
            flex-direction: column;
            align-items: center;
        }

        .login-btn {
            background: transparent;
            color: var(--primary-color);
            border: 1px solid var(--primary-color);
        }
        .logo i {
            font-size: 24px;
            color: white;
        }

        .brand {
            font-size: 16px;
            font-weight: 700;
            letter-spacing: 1px;
            color: white;
        }

        /* 导航图标 - 优化 */
        .nav-icons {
            display: flex;
            flex-direction: column;
            width: 100%;
            margin-top: 10px;
        }

        .nav-icons a {
            display: flex;
            flex-direction: column;
            align-items: center;
            padding: 18px 0;
            color: #aaa;
            text-decoration: none;
            transition: var(--transition);
            font-size: 12px;
            position: relative;
        }

        .nav-icons a:hover, .nav-icons a.active {
            color: white;
            background: rgba(255, 255, 255, 0.08);
        }

        .nav-icons a.active::before {
            content: '';
            position: absolute;
            left: 0;
            top: 0;
            height: 100%;
            width: 4px;
            background: var(--accent-color);
            border-radius: 0 4px 4px 0;
        }

        .nav-icons i {
            font-size: 22px;
            margin-bottom: 8px;
        }

        .toggle-btn {
            position: absolute;
            bottom: 20px;
            background: rgba(255,255,255,0.1);
            border: none;
            color: #ccc;
            width: 40px;
            height: 40px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            transition: var(--transition);
        }

        .toggle-btn:hover {
            background: rgba(255,255,255,0.2);
            color: white;
        }

        /* 主内容区域 */
        .main-content {
            flex: 1;
            display: flex;
            flex-direction: column;
        }

        /* 顶部栏 - 优化 */
        .topbar {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 18px 40px;
            background: rgba(255, 255, 255, 0.95);
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
            z-index: 90;
            position: sticky;
            top: 0;
            backdrop-filter: blur(10px);
            border-bottom: 1px solid rgba(0,0,0,0.05);
        }
        /* 头部简化 */
        .topbar {
            background: white;
            padding: 15px 30px;
            border-bottom: 1px solid #eee;
        }

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

        .btn {
            padding: 8px 16px;
            border-radius: 20px;
            font-size: 14px;
            transition: var(--transition);
        }

        .login-btn {
            background: transparent;
            color: var(--primary-color);
            border: 1px solid var(--primary-color);
        }

        .register-btn {
            background: var(--primary-color);
            color: white;
            border: 1px solid var(--primary-color);
        }


        /* 内容区优化 */
        .main-content {
            background: transparent;
        }

        .home-page, .list-page, .article-page {
            background: transparent;
            padding: 20px;
        }

        .hero {
            background: white;
            border-radius: var(--border-radius);
            box-shadow: var(--shadow);
            padding: 40px;
            margin-bottom: 30px;
        }
        /* 搜索框 - 优化 */
        .search-container {
            flex: 1;
            max-width: 700px;
            position: relative;
        }

        .search-input {
            width: 100%;
            padding: 14px 25px 14px 50px;
            border: none;
            border-radius: 50px;
            font-size: 16px;
            transition: var(--transition);
            background: #f1f3f9;
            box-shadow: inset 0 2px 5px rgba(0,0,0,0.03);
        }

        .search-input:focus {
            outline: none;
            background: white;
            box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.2), 
                        inset 0 2px 5px rgba(0,0,0,0.03);
        }

        .search-icon {
            position: absolute;
            left: 20px;
            top: 50%;
            transform: translateY(-50%);
            color: #94a3b8;
            font-size: 18px;
        }

        .user-actions {
            display: flex;
            align-items: center;
            gap: 20px;
        }

        .user-action-btn {
            width: 40px;
            height: 40px;
            border-radius: 50%;
            background: #f1f3f9;
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--dark-color);
            cursor: pointer;
            transition: var(--transition);
            position: relative;
        }

        .user-action-btn:hover {
            background: var(--primary-color);
            color: white;
        }

        .notification-badge {
            position: absolute;
            top: -5px;
            right: -5px;
            background: #ff4757;
            color: white;
            font-size: 10px;
            width: 18px;
            height: 18px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .user-profile {
            display: flex;
            align-items: center;
            gap: 12px;
            cursor: pointer;
        }

        .user-avatar {
            width: 42px;
            height: 42px;
            border-radius: 50%;
            background: var(--gradient);
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
            font-weight: 600;
            font-size: 18px;
        }

        .user-name {
            font-weight: 600;
            font-size: 15px;
        }

        /* 首页样式 - 优化 */
        .home-page {
            padding: 30px 40px;
            flex: 1;
        }

        .hero {
            text-align: center;
            padding: 60px 20px 80px;
            margin-bottom: 40px;
            background: var(--gradient);
            border-radius: var(--border-radius);
            color: white;
            position: relative;
            overflow: hidden;
            box-shadow: var(--shadow);
        }

        .hero::before {
            content: '';
            position: absolute;
            top: -50%;
            left: -50%;
            width: 200%;
            height: 200%;
            background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0) 70%);
            transform: rotate(30deg);
        }

        .hero-title {
            font-size: 3rem;
            margin-bottom: 20px;
            font-weight: 800;
            position: relative;
            z-index: 2;
        }

        .hero-subtitle {
            font-size: 1.2rem;
            max-width: 700px;
            margin: 0 auto 40px;
            opacity: 0.9;
            font-weight: 300;
            position: relative;
            z-index: 2;
        }

        .hero-search-container {
            max-width: 700px;
            margin: 0 auto;
            position: relative;
            z-index: 2;
        }

        .hero-search-input {
            width: 100%;
            padding: 18px 30px;
            border: none;
            border-radius: 50px;
            font-size: 18px;
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
            transition: var(--transition);
        }

        .hero-search-input:focus {
            outline: none;
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2), 
                        0 0 0 3px rgba(255,255,255,0.3);
        }

        .quick-links {
            display: flex;
            justify-content: center;
            gap: 15px;
            margin-top: 30px;
            position: relative;
            z-index: 2;
        }

        .quick-links a {
            background: rgba(255, 255, 255, 0.15);
            padding: 12px 25px;
            border-radius: 50px;
            text-decoration: none;
            color: #666;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
            transition: var(--transition);
            backdrop-filter: blur(5px);
            border: 1px solid rgba(255,255,255,0.1);
            font-weight: 500;
        }

        .quick-links a:hover {
            background: rgba(255, 255, 255, 0.25);
            transform: translateY(-3px);
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
        }

        .stats-container {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
            gap: 25px;
            margin: -40px auto 60px;
            max-width: 1200px;
            position: relative;
            z-index: 10;
        }

        .stat-card {
            background: var(--card-bg);
            border-radius: var(--border-radius);
            padding: 25px;
            box-shadow: var(--shadow);
            display: flex;
            align-items: center;
            transition: var(--transition);
        }

        .stat-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
        }

        .stat-icon {
            width: 60px;
            height: 60px;
            border-radius: 15px;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-right: 20px;
            font-size: 24px;
            color: white;
        }

        .icon-1 { background: linear-gradient(135deg, #4361ee, #4cc9f0); }
        .icon-2 { background: linear-gradient(135deg, #7209b7, #b5179e); }
        .icon-3 { background: linear-gradient(135deg, #f72585, #ff9e7d); }
        .icon-4 { background: linear-gradient(135deg, #06d6a0, #90e0ef); }

        .stat-content h3 {
            font-size: 24px;
            margin-bottom: 5px;
        }

        .stat-content p {
            color: #64748b;
            font-size: 14px;
        }

        .featured-section {
            margin-top: 30px;
        }

        .section-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 30px;
        }

        .section-title {
            font-size: 1.8rem;
            font-weight: 700;
            position: relative;
            padding-bottom: 15px;
        }

        .section-title::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 60px;
            height: 4px;
            background: var(--primary-color);
            border-radius: 2px;
        }

        .view-all {
            color: var(--primary-color);
            text-decoration: none;
            font-weight: 600;
            font-size: 15px;
            display: flex;
            align-items: center;
            gap: 5px;
            transition: var(--transition);
        }

        .view-all:hover {
            color: var(--secondary-color);
            gap: 8px;
        }

        .featured-content {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: 30px;
        }

        .featured-item {
            background: var(--card-bg);
            border-radius: var(--border-radius);
            overflow: hidden;
            box-shadow: var(--shadow);
            transition: var(--transition);
            position: relative;
            border: 1px solid rgba(0,0,0,0.03);
        }

        .featured-item:hover {
            transform: translateY(-8px);
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
        }

        .item-image {
            height: 180px;
            overflow: hidden;
        }

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

        .featured-item:hover .item-image img {
            transform: scale(1.08);
        }

        .item-content {
            padding: 20px;
        }

        .item-title {
            font-size: 18px;
            font-weight: 700;
            margin-bottom: 10px;
        }

        .item-description {
            color: #64748b;
            font-size: 14px;
            margin-bottom: 15px;
            line-height: 1.6;
        }

        .item-meta {
            display: flex;
            justify-content: space-between;
            color: #94a3b8;
            font-size: 13px;
        }

        /* 瀑布流样式 */
        .masonry-section {
            margin-top: 60px;
        }

        .masonry-grid {
            column-count: 3;
            column-gap: 25px;
        }

        .grid-item {
            break-inside: avoid;
            margin-bottom: 25px;
            background: var(--card-bg);
            border-radius: var(--border-radius);
            overflow: hidden;
            box-shadow: var(--shadow);
            transition: var(--transition);
            border: 1px solid rgba(0,0,0,0.03);
        }

        .grid-item:hover {
            transform: translateY(-5px);
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
        }

        .grid-item img {
            width: 100%;
            display: block;
        }

        .image-info {
            padding: 20px;
        }

        .image-info h3 {
            margin-bottom: 10px;
            font-size: 18px;
            font-weight: 700;
        }

        .image-info p {
            color: #64748b;
            font-size: 14px;
            line-height: 1.6;
        }

        /* 底部灰色优化 */
        .footer {
            background: var(--footer-bg);
            padding: 30px 0;
            border-top: 1px solid #eaeaea;
        }

        .footer-links {
            display: flex;
            justify-content: center;
            gap: 30px;
            margin-bottom: 20px;
        }

        .footer-links a {
            color: #666;
            text-decoration: none;
            font-size: 14px;
        }

        .copyright {
            text-align: center;
            color: #999;
            font-size: 13px;
        }

        /* 响应式设计 */
        @media (max-width: 1200px) {
            .masonry-grid {
                column-count: 2;
            }
        }

        @media (max-width: 992px) {
            .hero-title {
                font-size: 2.5rem;
            }
        }

        @media (max-width: 768px) {
            .layout {
                flex-direction: column;
            }
            
            .sidebar {
                width: 100%;
                height: auto;
                flex-direction: row;
                padding: 15px;
            }
            
            .sidebar-header {
                flex-direction: row;
                gap: 15px;
                margin-bottom: 0;
            }
            
            .nav-icons {
                flex-direction: row;
                justify-content: space-around;
                margin-top: 0;
            }
            
            .nav-icons a {
                padding: 15px 10px;
            }
            
            .toggle-btn {
                position: relative;
                bottom: auto;
                margin-left: auto;
            }
            
            .topbar {
                flex-direction: column;
                padding: 20px 15px;
                gap: 15px;
            }
            
            .search-container {
                width: 100%;
                margin-bottom: 10px;
            }
            
            .user-actions {
                align-self: flex-end;
            }
            
            .masonry-grid {
                column-count: 1;
            }
            
            .stats-container {
                grid-template-columns: 1fr;
                margin-top: 20px;
            }
        }

        @media (max-width: 576px) {
            .hero-title {
                font-size: 2rem;
            }
            
            .hero-search-input {
                padding: 16px 25px;
                font-size: 16px;
            }
            
            .featured-content {
                grid-template-columns: 1fr;
            }
            
            .hero {
                padding: 40px 15px 60px;
            }
            
            .quick-links {
                flex-wrap: wrap;
            }
            
            .footer-nav {
                flex-wrap: wrap;
                gap: 15px;
            }
        }
  /* 热门推荐布局优化 */
        .featured-content {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 25px;
            max-width: 1200px;
            margin: 0 auto;
        }

        .featured-item {
            background: white;
            border-radius: var(--border-radius);
            box-shadow: var(--shadow);
            transition: var(--transition);
            overflow: hidden;
        }

        .featured-item:hover {
            transform: translateY(-5px);
            box-shadow: 0 5px 15px rgba(0,0,0,0.08);
        }

        /* 底部灰色优化 */
        .footer {
            background: var(--footer-bg);
            padding: 30px 0;
            border-top: 1px solid #eaeaea;
        }

        .footer-links {
            display: flex;
            justify-content: center;
            gap: 30px;
            margin-bottom: 20px;
        }

        .footer-links a {
            color: #666;
            text-decoration: none;
            font-size: 14px;
        }

        .copyright {
            text-align: center;
            color: #999;
            font-size: 13px;
        }

        /* 折叠按钮样式 */
        .toggle-btn {
            position: absolute;
            bottom: 15px;
            left: 50%;
            transform: translateX(-50%);
            width: 30px;
            height: 30px;
            border-radius: 50%;
            background: white;
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            box-shadow: 0 2px 5px rgba(0,0,0,0.1);
            border: 1px solid #eee;
        }
        /* 新增折叠相关样式 */
        .sidebar {
            transition: all 0.3s ease;
        }
        .sidebar.collapsed {
            width: 60px;
        }
        .sidebar.collapsed .logo img {
            width: 40px;
            height: 40px;
        }
        .sidebar.collapsed .nav-icons span {
            display: none;
        }
        .sidebar.collapsed .toggle-btn i {
            transform: rotate(180deg);
        }
        .toggle-btn {
            position: absolute;
            bottom: 20px;
            left: 50%;
            transform: translateX(-50%);
            cursor: pointer;
            z-index: 10;
        }
        /*main-content.expanded {
            margin-left: 60px;
        }*/
        /* 移动端样式优化 */
        @media (max-width: 768px) {
            .sidebar {
                display: none;
            }
            
            .topbar {
                display: flex;
                justify-content: space-between;
                align-items: center;
                padding: 10px 15px;
            }
            
            .mobile-logo {
                display: block !important;
                height: 40px;
            }
            
            .mobile-logo img {
                height: 100%;
            }
            
            .main-content {
                margin-left: 0;
                padding-bottom: 60px; /* 为底部导航留出空间 */
            }
            
            .mobile-nav {
                display: flex;
                position: fixed;
                bottom: 0;
                left: 0;
                right: 0;
                background: #fff;
                box-shadow: 0 -2px 10px rgba(0,0,0,0.1);
                z-index: 1000;
            }
            
            .nav-item {
                flex: 1;
                text-align: center;
                padding: 10px 5px;
                font-size: 12px;
                color: #666;
            }
            
            .nav-item.active {
                color: #007bff;
            }
            
            .nav-item i {
                display: block;
                font-size: 20px;
                margin-bottom: 3px;
            }
        }
        
        /* 桌面端隐藏移动元素 */
        @media (min-width: 769px) {
            .mobile-nav {
                display: none;
            }
            
            .mobile-logo {
                display: none;
            }
        }
        
        /* 默认隐藏移动logo */
        .mobile-logo {
            display: none;
        }