/* ===== 基础变量 ===== */
        :root {
            --primary: #2196F3;
            --primary-light: #64B5F6;
            --primary-dark: #1976D2;
            --secondary: #E3F2FD;
            --bg-gradient-start: #F0F8FF;
            --bg-gradient-end: #E3F2FD;
            --card-bg: rgba(255, 255, 255, 0.85);
            --text-primary: #1565C0;
            --text-secondary: #546E7A;
            --text-light: #90A4AE;
            --shadow-light: rgba(33, 150, 243, 0.15);
            --shadow-medium: rgba(33, 150, 243, 0.25);
            --shadow-dark: rgba(25, 118, 210, 0.3);
            --neumorph-light: #FFFFFF;
            --neumorph-dark: #B0BEC5;
            --radius-sm: 12px;
            --radius-md: 16px;
            --radius-lg: 24px;
            --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }

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

        html {
            font-size: 16px;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
            background: linear-gradient(135deg, var(--bg-gradient-start) 0%, var(--bg-gradient-end) 50%, #BBDEFB 100%);
            min-height: 100vh;
            color: var(--text-primary);
            line-height: 1.6;
            overflow-x: hidden;
        }

        /* ===== 顶部区域 ===== */
        .header {
            background: linear-gradient(135deg, rgba(255,255,255,0.9) 0%, rgba(227,242,253,0.9) 100%);
            backdrop-filter: blur(20px);
            -webkit-backdrop-filter: blur(20px);
            border-bottom: 1px solid rgba(255,255,255,0.6);
            padding: 16px 0;
            position: sticky;
            top: 0;
            z-index: 100;
            box-shadow: 
                0 4px 20px var(--shadow-light),
                inset 0 1px 0 rgba(255,255,255,0.8);
        }

        .header-content {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
            display: flex;
            align-items: center;
            gap: 16px;
        }

        .logo-section {
            flex-shrink: 0;
        }

        .logo-wrapper {
            width: 56px;
            height: 56px;
            border-radius: var(--radius-md);
            background: linear-gradient(145deg, var(--neumorph-light), var(--secondary));
            box-shadow: 
                6px 6px 12px var(--shadow-light),
                -6px -6px 12px rgba(255,255,255,0.8),
                inset 0 0 0 2px rgba(255,255,255,0.5);
            display: flex;
            align-items: center;
            justify-content: center;
            overflow: hidden;
            transition: var(--transition);
        }

        .logo-wrapper:hover {
            transform: scale(1.05) rotate(2deg);
            box-shadow: 
                8px 8px 16px var(--shadow-medium),
                -8px -8px 16px rgba(255,255,255,0.9);
        }

        .logo {
            width: 44px;
            height: 44px;
            object-fit: cover;
            border-radius: var(--radius-sm);
        }

        .announcement-section {
            flex: 1;
            min-width: 0;
        }

        .announcement-box {
            background: linear-gradient(145deg, rgba(255,255,255,0.9), rgba(227,242,253,0.7));
            border-radius: var(--radius-md);
            padding: 12px 16px;
            display: flex;
            align-items: center;
            gap: 12px;
            box-shadow: 
                4px 4px 8px var(--shadow-light),
                -4px -4px 8px rgba(255,255,255,0.7),
                inset 0 1px 0 rgba(255,255,255,0.8);
            border: 1px solid rgba(255,255,255,0.5);
        }

        .announcement-icon {
            flex-shrink: 0;
            width: 28px;
            height: 28px;
            background: linear-gradient(135deg, var(--primary-light), var(--primary));
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
            font-size: 14px;
            box-shadow: 0 2px 8px var(--shadow-medium);
        }

        .announcement-content {
            flex: 1;
            min-width: 0;
        }

        .announcement-content p {
            font-size: 13px;
            color: var(--text-secondary);
            line-height: 1.7;
            margin: 0;
        }

        /* ===== 公告按钮样式 ===== */
        .announcement-buttons {
            display: flex;
            gap: 10px;
            flex-wrap: wrap;
            justify-content: center;
            margin-top: 10px;
        }

        .announcement-btn {
            flex: 1;
            min-width: 120px;
            padding: 12px 16px;
            border-radius: 25px;
            text-decoration: none;
            font-size: 14px;
            font-weight: 600;
            text-align: center;
            transition: all 0.3s ease;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 6px;
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
            border: none;
            cursor: pointer;
            background: rgba(255,255,255, 0.9);
            color: var(--text-primary);
            backdrop-filter: blur(10px);
        }

        .announcement-btn:first-child {
            background: rgba(0, 153, 255, 0.9);
            color: white;
        }

        .announcement-btn:last-child {
            background: rgba(255, 51, 51, 0.9);
            color: white;
        }

        .announcement-btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
        }

        /* ===== 主体内容区 ===== */
        .main-content {
            padding: 24px 0 80px;
            min-height: calc(100vh - 200px);
        }

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

        /* 应用网格 */
        .app-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
            gap: 15px;
            padding: 10px;
        }

        .app-card {
            background: rgba(255, 255, 255, 0.85);
            border-radius: var(--radius-md);
            padding: 4px;
            box-shadow: 
                6px 6px 16px var(--shadow-light),
                -6px -6px 16px rgba(255,255,255,0.8),
                inset 0 0 0 1px rgba(255,255,255,0.6);
            transition: var(--transition);
            cursor: pointer;
            position: relative;
            overflow: hidden;
            backdrop-filter: blur(10px);
        }

        .app-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 3px;
            background: linear-gradient(90deg, var(--primary-light), var(--primary), var(--primary-dark));
            opacity: 0;
            transition: var(--transition);
        }

        .app-card:hover {
            transform: translateY(-4px);
            box-shadow: 
                12px 12px 24px var(--shadow-medium),
                -8px -8px 20px rgba(255,255,255,0.9);
        }

        .app-card:hover::before {
            opacity: 1;
        }

        .card-content {
            background: linear-gradient(145deg, rgba(255,255,255, 0.95), rgba(240,248,255, 0.9));
            border-radius: calc(var(--radius-md) - 4px);
            padding: 16px;
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 12px;
            text-align: center;
        }

        .app-icon-wrapper {
            width: 64px;
            height: 64px;
            border-radius: var(--radius-sm);
            background: linear-gradient(145deg, var(--neumorph-light), var(--secondary));
            box-shadow: 
                4px 4px 8px var(--shadow-light),
                -4px -4px 8px rgba(255,255,255, 0.8);
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
            overflow: hidden;
        }

        .app-icon {
            width: 52px;
            height: 52px;
            object-fit: cover;
            border-radius: 10px;
        }

        .app-info {
            flex: 1;
            min-width: 0;
        }

        .app-name {
            font-size: 14px;
            font-weight: 600;
            color: var(--text-primary);
            margin-bottom: 4px;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .app-desc {
            font-size: 12px;
            color: var(--text-secondary);
            line-height: 1.4;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }

        /* ===== 隐藏下载按钮 ===== */
        .download-btn {
            display: none;
        }

        /* ===== 底部区域 ===== */
        .footer {
            background: linear-gradient(180deg, transparent, rgba(227,242,253,0.5));
            padding: 30px 20px;
            text-align: center;
        }

        .about-link {
            color: var(--text-secondary);
            text-decoration: none;
            font-size: 14px;
            padding: 10px 24px;
            border-radius: 30px;
            background: linear-gradient(145deg, rgba(255,255,255,0.9), rgba(227,242,253,0.7));
            box-shadow: 
                4px 4px 8px var(--shadow-light),
                -4px -4px 8px rgba(255,255,255,0.7);
            transition: var(--transition);
            display: inline-block;
            backdrop-filter: blur(10px);
        }

        .about-link:hover {
            color: var(--primary);
            transform: translateY(-2px);
            box-shadow: 
                6px 6px 12px var(--shadow-medium),
                -6px -6px 12px rgba(255,255,255,0.8);
        }

        /* ===== 教程悬浮按钮 ===== */
        .tutorial-float-btn {
            position: fixed;
            bottom: 24px;
            right: 24px;
            background: linear-gradient(135deg, var(--primary-light), var(--primary));
            color: white;
            border: none;
            width: 50px;
            height: 50px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            box-shadow: 
                0 4px 15px var(--shadow-dark),
                inset 0 1px 0 rgba(255,255,255,0.3);
            transition: var(--transition);
            z-index: 99;
        }

        .tutorial-float-btn:hover {
            transform: translateY(-3px) scale(1.05);
            box-shadow: 
                0 8px 25px var(--shadow-dark),
                inset 0 1px 0 rgba(255,255,255,0.4);
        }

        .tutorial-float-btn:active {
            transform: translateY(-1px) scale(0.95);
        }

        /* ===== 响应式设计 ===== */
        @media (max-width: 480px) {
            .header-content {
                flex-direction: column;
                gap: 12px;
                padding: 0 16px;
            }
            
            .logo-wrapper {
                width: 48px;
                height: 48px;
            }
            
            .logo {
                width: 38px;
                height: 38px;
            }
            
            .announcement-box {
                padding: 10px 12px;
            }
            
            .announcement-content p {
                font-size: 12px;
            }
            
            .announcement-buttons {
                flex-direction: column;
            }
            
            .announcement-btn {
                min-width: auto;
                width: 100%;
            }
            
            .main-content {
                padding: 16px 0 100px;
            }
            
            .container {
                padding: 0 12px;
            }
            
            .app-grid {
                grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
                gap: 12px;
            }
            
            .card-content {
                padding: 14px;
            }
            
            .app-icon-wrapper {
                width: 56px;
                height: 56px;
            }
            
            .app-icon {
                width: 44px;
                height: 44px;
            }
            
            .app-name {
                font-size: 13px;
            }
            
            .app-desc {
                font-size: 11px;
            }
        }

        @media (max-width: 360px) {
            .app-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            
            .logo-wrapper {
                width: 42px;
                height: 42px;
            }
            
            .logo {
                width: 32px;
                height: 32px;
            }
        }

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

        .app-card {
            animation: fadeInUp 0.5s ease-out forwards;
        }

        .app-card:nth-child(1) { animation-delay: 0.05s; }
        .app-card:nth-child(2) { animation-delay: 0.1s; }
        .app-card:nth-child(3) { animation-delay: 0.15s; }
        .app-card:nth-child(4) { animation-delay: 0.2s; }
        .app-card:nth-child(5) { animation-delay: 0.25s; }
        .app-card:nth-child(6) { animation-delay: 0.3s; }
        
          /* 公告按钮样式 */
            .announcement-buttons {
                display: flex;
                gap: 15px;
                margin-top: 15px;
                justify-content: center;
                width: 100%;
                flex-wrap: wrap; /* 移动端换行显示 */
            }
            
            .announcement-btn {
                flex: 0 0 auto;
                padding: 12px 24px;
                border-radius: 25px;
                text-decoration: none;
                font-size: 16px;
                font-weight: 600;
                text-align: center;
                transition: all 0.3s ease;
                display: flex;
                align-items: center;
                justify-content: center;
                gap: 8px;
                box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
                white-space: nowrap;
            }
            
            .announcement-btn:first-child {
                background: #0099ff;
                color: white;
            }
            
            .announcement-btn:last-child {
                background: #ff3333;
                color: white;
            }
            
            .announcement-btn:hover {
                transform: translateY(-2px);
                box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
            }
            
            /* 隐藏下载按钮 */
            .download-btn {
                display: none;
            }
            
            /* 图标区域样式 */
            .app-icon-wrapper {
                cursor: pointer;
            }
            
            .app-icon {
                cursor: pointer;
            }

            /* 移动端适配样式 */
            @media screen and (max-width: 768px) {
                .header-content {
                    flex-direction: column;
                    align-items: center;
                    padding: 10px;
                }
                
                .logo-section {
                    margin-bottom: 15px;
                }
                
                .logo {
                    max-width: 150px;
                    height: auto;
                }
                
                .announcement-section {
                    width: 100%;
                    max-width: 500px;
                }
                
                .announcement-box {
                    padding: 12px;
                }
                
                .announcement-content p {
                    font-size: 14px;
                    margin-bottom: 10px;
                }
                
                .announcement-btn {
                    padding: 10px 16px;
                    font-size: 14px;
                    min-width: 120px;
                }
                
                .app-grid {
                    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
                    gap: 12px;
                    padding: 10px;
                }
                
                .app-card {
                    min-height: 160px;
                }
                
                .app-icon {
                    width: 50px;
                    height: 50px;
                }
                
                .app-name {
                    font-size: 14px;
                }
                
                .app-desc {
                    font-size: 12px;
                }
            }
            
            @media screen and (max-width: 480px) {
                .announcement-buttons {
                    flex-direction: column;
                    align-items: center;
                }
                
                .announcement-btn {
                    width: 100%;
                    max-width: 250px;
                }
                
                .app-grid {
                    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
                    gap: 10px;
                }
                
                .app-card {
                    min-height: 140px;
                }
                
                .app-icon {
                    width: 45px;
                    height: 45px;
                }
                
                .app-name {
                    font-size: 13px;
                }
                
                .app-desc {
                    font-size: 11px;
                }
            }
            
            @media screen and (max-width: 360px) {
                .app-grid {
                    grid-template-columns: repeat(2, 1fr);
                }
                
                .announcement-btn {
                    padding: 8px 12px;
                    font-size: 13px;
                }
            }