* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Comic Sans MS', '微软雅黑', sans-serif;
        }
        
        body {
            background-color: #f0f9ff;
            color: #333;
            line-height: 1.6;
            padding-bottom: 50px;
            background-image: 
                radial-gradient(#b3e5fc 2px, transparent 2px),
                radial-gradient(#ffccbc 2px, transparent 2px);
            background-size: 50px 50px;
            background-position: 0 0, 25px 25px;
        }
        
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        
        header {
            background: linear-gradient(135deg, #6ecbf5 0%, #059dc5 100%);
            color: white;
            padding: 25px 0;
            border-radius: 0 0 25px 25px;
            box-shadow: 0 5px 15px rgba(0, 150, 200, 0.3);
            position: relative;
            overflow: hidden;
        }
        
        .header-content {
            display: flex;
            justify-content: space-between;
            align-items: center;
            position: relative;
            z-index: 2;
        }
        
        .logo {
            display: flex;
            align-items: center;
        }
        
        .logo i {
            font-size: 3rem;
            margin-right: 15px;
            color: #ffde59;
            text-shadow: 2px 2px 0 #ff9800;
        }
        
        .logo-text h1 {
            font-size: 2.2rem;
            margin-bottom: 5px;
            text-shadow: 2px 2px 0 rgba(0, 0, 0, 0.1);
        }
        
        .logo-text p {
            font-size: 1.1rem;
            opacity: 0.9;
        }
        
        .class-info {
            background-color: rgba(255, 255, 255, 0.2);
            padding: 10px 20px;
            border-radius: 15px;
            backdrop-filter: blur(5px);
        }
        
        .decoration {
            position: absolute;
            z-index: 1;
        }
        
        .decoration.cpu {
            top: 10px;
            right: 10px;
            font-size: 5rem;
            color: rgba(255, 255, 255, 0.1);
        }
        
        .decoration.code {
            bottom: 10px;
            left: 10px;
            font-size: 4rem;
            color: rgba(255, 255, 255, 0.1);
        }
        
        .nav-tabs {
            display: flex;
            justify-content: center;
            margin: 30px 0 40px;
            flex-wrap: wrap;
            gap: 10px;
        }
        
        .tab-btn {
            padding: 15px 25px;
            background-color: white;
            border: none;
            border-radius: 50px;
            font-size: 1.2rem;
            font-weight: bold;
            color: #059dc5;
            cursor: pointer;
            transition: all 0.3s ease;
            box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
            display: flex;
            align-items: center;
            gap: 8px;
        }
        
        .tab-btn:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 15px rgba(0, 0, 0, 0.15);
            background-color: #ffde59;
            color: #333;
        }
        
        .tab-btn.active {
            background-color: #ff9800;
            color: white;
            box-shadow: 0 8px 15px rgba(255, 152, 0, 0.3);
        }
        
        .tab-content {
            display: none;
            background-color: white;
            border-radius: 25px;
            padding: 30px;
            box-shadow: 0 10px 25px rgba(0, 0, 0, 0.08);
            margin-bottom: 30px;
            animation: fadeIn 0.5s ease;
        }
        
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(10px); }
            to { opacity: 1; transform: translateY(0); }
        }
        
        .tab-content.active {
            display: block;
        }
        
        .section-title {
            color: #059dc5;
            font-size: 1.8rem;
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 3px dashed #6ecbf5;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        
        .section-title i {
            color: #ff9800;
        }
        
        .outline-content {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
            gap: 20px;
        }
        
        .outline-card {
            background-color: #f9f9f9;
            border-radius: 15px;
            padding: 20px;
            border-left: 5px solid #6ecbf5;
            transition: transform 0.3s ease;
        }
        
        .outline-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
        }
        
        .outline-card h3 {
            color: #ff9800;
            margin-bottom: 10px;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        
        .knowledge-points {
            display: flex;
            flex-direction: column;
            gap: 25px;
        }
        
        .point-card {
            background-color: #e8f4fc;
            border-radius: 15px;
            padding: 20px;
            border: 2px solid #b3e5fc;
        }
        
        .point-title {
            color: #ff5722;
            font-size: 1.3rem;
            margin-bottom: 10px;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        
        .example-card {
            background-color: #fff8e1;
            border-radius: 15px;
            padding: 20px;
            margin-bottom: 20px;
            border: 2px solid #ffecb3;
        }
        
        .example-title {
            color: #8bc34a;
            font-size: 1.3rem;
            margin-bottom: 15px;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        
        .code-block {
            background-color: #263238;
            color: #f8f8f2;
            border-radius: 10px;
            padding: 20px;
            margin: 15px 0;
            overflow-x: auto;
            font-family: 'Courier New', monospace;
            font-size: 0.95rem;
        }
        
        .code-keyword {
            color: #ff79c6;
        }
        
        .code-comment {
            color: #6272a4;
        }
        
        .code-function {
            color: #50fa7b;
        }
        
        .game-container {
            text-align: center;
        }
        
        .game-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 30px;
            flex-wrap: wrap;
            gap: 15px;
        }
        
        .game-stats {
            display: flex;
            gap: 20px;
            background-color: #e8f4fc;
            padding: 15px;
            border-radius: 15px;
        }
        
        .game-level {
            font-size: 1.5rem;
            color: #ff5722;
            font-weight: bold;
        }
        
        .game-question {
            background-color: #f9f9f9;
            padding: 30px;
            border-radius: 20px;
            margin-bottom: 30px;
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
            min-height: 200px;
            display: flex;
            flex-direction: column;
            justify-content: center;
        }
        
        .game-options {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 15px;
            margin-bottom: 30px;
        }
        
        .game-option {
            padding: 20px;
            background-color: white;
            border: 3px solid #6ecbf5;
            border-radius: 15px;
            cursor: pointer;
            transition: all 0.3s ease;
            font-size: 1.1rem;
        }
        
        .game-option:hover {
            background-color: #6ecbf5;
            color: white;
            transform: scale(1.03);
        }
        
        .game-option.correct {
            background-color: #8bc34a;
            color: white;
            border-color: #689f38;
        }
        
        .game-option.wrong {
            background-color: #ff5722;
            color: white;
            border-color: #d84315;
        }
        
        .game-controls {
            display: flex;
            justify-content: center;
            gap: 20px;
            margin-top: 20px;
        }
        
        .game-btn {
            padding: 15px 30px;
            border: none;
            border-radius: 50px;
            font-size: 1.2rem;
            font-weight: bold;
            cursor: pointer;
            transition: all 0.3s ease;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        
        .game-btn.next {
            background-color: #8bc34a;
            color: white;
        }
        
        .game-btn.restart {
            background-color: #ff9800;
            color: white;
        }
        
        .game-btn:hover {
            transform: translateY(-3px);
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
        }
        
        .game-result {
            display: none;
            background-color: #e8f4fc;
            padding: 40px;
            border-radius: 20px;
            margin-top: 20px;
            text-align: center;
        }
        
        .game-result.show {
            display: block;
            animation: fadeIn 0.5s ease;
        }
        
        .celebration {
            font-size: 4rem;
            color: #ffde59;
            margin-bottom: 20px;
            animation: bounce 1s infinite alternate;
        }
        
        @keyframes bounce {
            from { transform: translateY(0); }
            to { transform: translateY(-20px); }
        }
        
        footer {
            text-align: center;
            margin-top: 50px;
            padding-top: 20px;
            border-top: 2px dashed #6ecbf5;
            color: #666;
        }
        
        .character {
            position: fixed;
            bottom: 20px;
            right: 20px;
            width: 100px;
            height: 120px;
            z-index: 100;
            pointer-events: none;
        }
        
        .character-body {
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            width: 60px;
            height: 80px;
            background-color: #6ecbf5;
            border-radius: 30px 30px 0 0;
        }
        
        .character-head {
            position: absolute;
            bottom: 80px;
            left: 50%;
            transform: translateX(-50%);
            width: 70px;
            height: 70px;
            background-color: #ffde59;
            border-radius: 50%;
        }
        
        .character-eye {
            position: absolute;
            top: 20px;
            width: 10px;
            height: 10px;
            background-color: #333;
            border-radius: 50%;
        }
        
        .character-eye.left {
            left: 20px;
        }
        
        .character-eye.right {
            right: 20px;
        }
        
        @media (max-width: 768px) {
            .header-content {
                flex-direction: column;
                text-align: center;
                gap: 20px;
            }
            
            .nav-tabs {
                flex-direction: column;
                align-items: center;
            }
            
            .tab-btn {
                width: 90%;
                justify-content: center;
            }
            
            .game-header {
                flex-direction: column;
                text-align: center;
            }
            
            .character {
                display: none;
            }
        }
/* 页脚导航链接样式 */
    .footer-nav {
      margin: 15px 0;
      text-align: center;
    }
    .footer-nav a {
      color: #17a2b8;
      text-decoration: none;
      margin: 0 15px;
      padding: 5px 10px;
      border-radius: 4px;
      transition: all 0.3s;
    }
    .footer-nav a:hover {
      background-color: #e8f4f8;
      color: #0c7b8c;
    }
    .footer-nav a i {
      margin-right: 5px;
    }