* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Courier New', monospace;
    background: linear-gradient(135deg, #667eea 0%, #9052cd 100%);
    color: white;
    min-height: 100vh;
    cursor: crosshair;
}

.container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    padding: 20px;
}

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

.header h1 {
    font-size: clamp(2em, 5vw, 3em);
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.header p {
    font-size: clamp(1em, 2.5vw, 1.2em);
    opacity: 0.8;
}

.key-guide {
    background: rgba(255,255,255,0.1);
    border-radius: 10px;
    padding: 15px;
    margin-bottom: 20px;
    backdrop-filter: blur(10px);
    text-align: center;
}

.key-guide h4 {
    margin-bottom: 10px;
    color: #ff6b6b;
}

.key-info {
    display: flex;
    justify-content: center;
    gap: 30px;
    flex-wrap: wrap;
}

.key-info span {
    font-size: clamp(0.8em, 2vw, 1em);
}

.song-guide {
    background: rgba(255,255,255,0.1);
    border-radius: 10px;
    padding: 20px;
    margin-bottom: 20px;
    backdrop-filter: blur(10px);
    text-align: center;
}

.song-guide h4 {
    margin-bottom: 15px;
    color: #4ecdc4;
}

.songs-container {
    display: flex;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
}

.song-card {
    background: rgba(0,0,0,0.2);
    border-radius: 10px;
    padding: 15px;
    min-width: 180px;
    max-width: 220px;
    flex: 1 1 180px;
    border: 2px solid transparent;
    transition: all 0.3s ease;
    cursor: pointer;
}

.song-card:hover {
    border-color: rgba(255,255,255,0.3);
    transform: translateY(-2px);
    background: rgba(0,0,0,0.3);
}

.song-title {
    font-size: 1.1em;
    font-weight: bold;
    margin-bottom: 8px;
    color: #ffa726;
}

.song-keys {
    font-family: 'Courier New', monospace;
    font-size: clamp(1em, 2.5vw, 1.3em);
    font-weight: bold;
    color: #ffffff;
    margin-bottom: 5px;
    letter-spacing: 2px;
}

.song-notes {
    font-size: 0.9em;
    color: rgba(255,255,255,0.7);
    margin-bottom: 12px;
}

.play-song-btn {
    background: rgba(255,107,107,0.3);
    border: 1px solid #ff6b6b;
    color: white;
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.9em;
    cursor: pointer;
    transition: all 0.3s ease;
}

.play-song-btn:hover {
    background: rgba(255,107,107,0.5);
    transform: scale(1.05);
}

.song-card.playing {
    border-color: #4ecdc4;
    background: rgba(78,205,196,0.1);
}

.song-card.playing .play-song-btn {
    background: rgba(78,205,196,0.5);
    border-color: #4ecdc4;
}

.main-content {
    display: flex;
    flex: 1;
    gap: 20px;
}

.activity-panel, .music-panel {
    flex: 1;
    background: rgba(255,255,255,0.1);
    border-radius: 15px;
    padding: 20px;
    backdrop-filter: blur(10px);
}

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

button {
    padding: 12px 24px;
    border: none;
    border-radius: 25px;
    background: rgba(255,255,255,0.2);
    color: white;
    cursor: pointer;
    font-size: 16px;
    transition: all 0.3s ease;
    white-space: nowrap;
}

button:hover {
    background: rgba(255,255,255,0.3);
    transform: translateY(-2px);
}

button.active {
    background: rgba(255,255,255,0.4);
}

.activity-log {
    height: 200px;
    min-height: 150px;
    overflow-y: auto;
    background: rgba(0,0,0,0.2);
    border-radius: 10px;
    padding: 15px;
    font-family: monospace;
    font-size: 14px;
}

.activity-item {
    margin-bottom: 8px;
    padding: 5px;
    border-left: 3px solid #ff6b6b;
    padding-left: 10px;
    animation: fadeInLeft 0.5s ease;
}

.activity-item.piano {
    border-left-color: #4ecdc4;
}

.activity-item.guitar {
    border-left-color: #ffa726;
}

.activity-item.mouse-move {
    border-left-color: #9c27b0;
    opacity: 0.8;
}

@keyframes fadeInLeft {
    from { opacity: 0; transform: translateX(-20px); }
    to { opacity: 1; transform: translateX(0); }
}

.visualizer {
    height: 150px;
    min-height: 100px;
    background: rgba(0,0,0,0.2);
    border-radius: 10px;
    margin-top: 20px;
    position: relative;
    overflow: hidden;
}

.wave {
    position: absolute;
    bottom: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(180deg, transparent 0%, rgba(255,107,107,0.3) 100%);
    animation: wave 2s ease-in-out infinite;
}

@keyframes wave {
    0%, 100% { transform: scaleY(0.5); }
    50% { transform: scaleY(1); }
}

.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
    gap: 15px;
    margin-top: 20px;
}

.stat-card {
    background: rgba(0,0,0,0.2);
    padding: 15px;
    border-radius: 10px;
    text-align: center;
}

.stat-number {
    font-size: clamp(1.5em, 4vw, 2em);
    font-weight: bold;
    color: #ff6b6b;
}

.stat-label {
    font-size: clamp(0.8em, 2vw, 0.9em);
    opacity: 0.7;
    margin-top: 5px;
}

.current-note {
    font-size: clamp(1.2em, 3vw, 1.5em);
    font-weight: bold;
    color: #4ecdc4;
    text-align: center;
    margin-top: 10px;
    min-height: 30px;
}

/* Responsive design */
@media (max-width: 768px) {
    .main-content {
        flex-direction: column;
    }
    
    .songs-container {
        flex-direction: column;
        align-items: center;
    }
    
    .song-card {
        max-width: 300px;
        width: 100%;
    }
    
    .key-info {
        flex-direction: column;
        gap: 10px;
    }
    
    .controls {
        flex-wrap: wrap;
        gap: 5px;
    }
    
    button {
        flex: 1;
        min-width: 120px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 10px;
    }
    
    .header {
        margin-bottom: 20px;
    }
    
    .song-guide, .key-guide {
        padding: 15px;
        margin-bottom: 15px;
    }
    
    .activity-panel, .music-panel {
        padding: 15px;
    }
    
    .activity-log {
        height: 150px;
    }
    
    .visualizer {
        height: 120px;
    }
}