:root {
    --primary-color: #4361ee;
    --bg-color: #f8f9fa;
    --panel-color: #ffffff;
    --text-color: #2b2d42;
    --border-color: #e9ecef;
    --shadow-color: rgba(0, 0, 0, 0.1);
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    overflow: hidden;
    height: 100vh;
}

.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    position: relative;
}

.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    background-color: var(--panel-color);
    box-shadow: 0 2px 10px var(--shadow-color);
    z-index: 10;
}

.app-header h1 {
    font-size: 1.2rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.controls {
    display: flex;
    gap: 0.8rem;
}

.control-btn {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-color);
    width: 36px;
    height: 36px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s ease;
    font-size: 0.9rem;
}

.control-btn:hover {
    background: rgba(0, 0, 0, 0.05);
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.control-btn.large {
    width: 48px;
    height: 48px;
    font-size: 1.2rem;
}

.visualizer-container {
    flex: 1;
    position: relative;
    overflow: hidden;
}

canvas {
    display: block;
    width: 100%;
    height: 100%;
    background-color: var(--bg-color);
}

.audio-controls {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    width: 90%;
    max-width: 600px;
    background-color: var(--panel-color);
    padding: 1.2rem;
    border-radius: 12px;
    box-shadow: 0 4px 20px var(--shadow-color);
    border: 1px solid var(--border-color);
    z-index: 5;
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
}

.source-selector {
    display: flex;
    justify-content: center;
    gap: 0.8rem;
}

.source-btn {
    background: rgba(0, 0, 0, 0.03);
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 0.5rem 1rem;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    font-weight: 500;
    font-size: 0.85rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.source-btn:hover {
    background: rgba(0, 0, 0, 0.05);
}

.source-btn.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.sample-songs {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    max-height: 150px;
    overflow-y: auto;
    padding: 0.5rem;
    border-radius: 8px;
    background: rgba(0, 0, 0, 0.03);
}

.sample-song {
    padding: 0.5rem;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    justify-content: space-between;
}

.sample-song:hover {
    background: rgba(0, 0, 0, 0.05);
}

.sample-song.active {
    background: var(--primary-color);
    color: white;
}

.song-info {
    display: flex;
    justify-content: space-between;
    font-size: 0.9rem;
}

#now-playing {
    font-weight: 500;
}

#song-progress {
    opacity: 0.7;
}

.playback-controls {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1.5rem;
}

.volume-control {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    width: 120px;
}

.volume-control i {
    font-size: 1rem;
    color: var(--text-color);
    opacity: 0.7;
}

input[type="range"] {
   
    height: 4px;
    background: var(--border-color);
    border-radius: 4px;
    outline: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
}

.visualization-info {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
}

.info-box {
    display: flex;
    flex-direction: column;
    align-items: center;
    font-size: 0.85rem;
}

.info-box span:first-child {
    opacity: 0.7;
    margin-bottom: 0.2rem;
}

.info-box span:last-child {
    font-weight: 500;
    color: var(--primary-color);
}

.settings-panel {
    position: absolute;
    top: 70px;
    right: 20px;
    background-color: var(--panel-color);
    padding: 1rem;
    border-radius: 8px;
    box-shadow: 0 4px 20px var(--shadow-color);
    border: 1px solid var(--border-color);
    z-index: 5;
    display: none;
    flex-direction: column;
    gap: 1rem;
    width: 220px;
}

.settings-panel.active {
    display: flex;
}

.setting-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.setting-group label {
    font-size: 0.85rem;
    font-weight: 500;
}

.setting-group select, .setting-group input {
    width: 100%;
    padding: 0.5rem;
    border-radius: 6px;
    border: 1px solid var(--border-color);
    background: white;
    font-family: 'Inter', sans-serif;
}

@media (max-width: 768px) {
    .app-header {
        padding: 1rem;
    }
    
    .audio-controls {
        bottom: 10px;
        padding: 1rem;
    }
    
    .settings-panel {
        top: auto;
        bottom: 100px;
        right: 10px;
        left: 10px;
        width: auto;
    }
    
    .source-selector {
        flex-wrap: wrap;
    }
}