* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }

        body {
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            min-height: 100vh;
            background: linear-gradient(135deg, #1a2a6c, #2c3e50);
            padding: 20px;
            color: #fff;
        }

        .container {
            width: 100%;
            max-width: 900px;
        }

        header {
            text-align: center;
            margin-bottom: 30px;
        }

        h1 {
            font-size: 2.5rem;
            margin-bottom: 10px;
            text-shadow: 0 2px 4px rgba(0,0,0,0.3);
            background: linear-gradient(90deg, #3498db, #8e44ad);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }

        .display-area {
            background: rgba(0, 0, 0, 0.3);
            border-radius: 15px;
            padding: 20px;
            margin-bottom: 30px;
            text-align: center;
            box-shadow: 0 5px 15px rgba(0,0,0,0.2);
        }

        .display-label {
            font-size: 1.2rem;
            margin-bottom: 10px;
            color: #bbb;
        }

        .note-display {
            background: linear-gradient(90deg, #2c3e50, #1a2a6c);
            height: 80px;
            border-radius: 10px;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            font-size: 2.5rem;
            font-weight: bold;
            box-shadow: inset 0 0 10px rgba(0,0,0,0.5);
        }

        .current-note {
            color: #3498db;
            font-size: 1.5rem;
        }

        .piano-container {
            background: #2c3e50;
            border-radius: 20px;
            padding: 30px;
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.5);
            position: relative;
            overflow: hidden;
        }

        .piano {
            display: flex;
            position: relative;
            height: 300px;
            border-radius: 10px;
            overflow: hidden;
            background: #34495e;
        }

        /* 白键样式 */
        .white-key {
            position: relative;
            flex: 1;
            height: 100%;
            background: linear-gradient(to bottom, #f9f9f9 95%, #e6e6e6);
            border-right: 1px solid #bbb;
            border-bottom: 8px solid #bbb;
            cursor: pointer;
            display: flex;
            flex-direction: column;
            justify-content: flex-end;
            align-items: center;
            padding-bottom: 15px;
            transition: all 0.08s ease;
            z-index: 1;
        }

        .white-key:last-child {
            border-right: none;
        }

        .white-key.active {
            background: linear-gradient(to bottom, #c8e6f9, #3498db);
            border-bottom-color: #2980b9;
            transform: translateY(4px);
        }

        .white-key .note {
            font-size: 1.3rem;
            font-weight: bold;
            color: #333;
        }

        .white-key .key {
            margin-top: 8px;
            background: rgba(0, 0, 0, 0.15);
            color: #fff;
            padding: 4px 8px;
            border-radius: 4px;
            font-size: 0.9rem;
            font-weight: 600;
        }

        /* 黑键样式 */
        .black-key {
            position: absolute;
            width: 8%;
            height: 60%;
            background: linear-gradient(to bottom, #111, #000);
            border-radius: 0 0 8px 8px;
            border-bottom: 8px solid #111;
            cursor: pointer;
            z-index: 2;
            transition: all 0.08s ease;
            box-shadow: 0 2px 5px rgba(0,0,0,0.7);
        }

        .black-key.active {
            background: linear-gradient(to bottom, #34495e, #3498db);
            border-bottom-color: #2980b9;
            transform: translateY(4px);
        }

        .black-key .note {
            color: #fff;
            font-weight: bold;
            margin-top: 120px;
        }

        .black-key .key {
            margin-top: 8px;
            background: rgba(255, 255, 255, 0.2);
            color: #fff;
            padding: 4px 8px;
            border-radius: 4px;
            font-size: 0.9rem;
            font-weight: 600;
        }

        /* 黑键定位 - 符合真实钢琴布局 */
        .key-cs { left: 6%; }
        .key-ds { left: 19%; }
        .key-fs { left: 44%; }
        .key-gs { left: 56.5%; }
        .key-as { left: 69%; }

        /* 白键标签定位 */
        .key-c { z-index: 1; }
        .key-d { z-index: 1; }
        .key-e { z-index: 1; }
        .key-f { z-index: 1; }
        .key-g { z-index: 1; }
        .key-a { z-index: 1; }
        .key-b { z-index: 1; }
        .key-c1 { z-index: 1; }

        .instructions {
            margin-top: 30px;
            text-align: center;
        }

        .keymap-container {
            background: rgba(255, 255, 255, 0.1);
            border-radius: 10px;
            padding: 15px;
            margin-top: 15px;
        }

        .keymap {
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            gap: 20px;
            margin-top: 10px;
        }

        .keymap-item {
            display: flex;
            flex-direction: column;
            align-items: center;
            margin: 5px 0;
        }

        .keymap-key {
            background: rgba(255, 255, 255, 0.2);
            color: white;
            width: 40px;
            height: 40px;
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: bold;
            font-size: 1.1rem;
            margin-bottom: 5px;
            box-shadow: 0 3px 6px rgba(0,0,0,0.3);
        }

        .keymap-note {
            font-size: 0.9rem;
            color: #ccc;
        }

        .footer {
            margin-top: 30px;
            text-align: center;
            color: #bbb;
            font-size: 0.9rem;
        }

        .copyright {
            margin-top: 20px;
            color: #999;
            font-size: 0.9rem;
        }

        /* 响应式设计 */
        @media (max-width: 768px) {
            .piano {
                height: 250px;
            }
            
            .note-display {
                font-size: 2rem;
                height: 70px;
            }
            
            .white-key .note {
                font-size: 1.1rem;
            }
            
            .black-key {
                width: 9%;
            }
        }

        @media (max-width: 480px) {
            h1 {
                font-size: 2rem;
            }
            
            .piano {
                height: 200px;
            }
            
            .white-key .note, 
            .white-key .key {
                font-size: 0.8rem;
            }
            
            .black-key .note, 
            .black-key .key {
                font-size: 0.8rem;
            }
            
            .keymap-key {
                width: 35px;
                height: 35px;
                font-size: 0.9rem;
            }
        }