body {
    font-family: Arial;
    background: #f5f5f5;
    padding: 20px;
}

.container {
    max-width: 600px;
    margin: auto;
}

.track-box {
    background: white;
    padding: 15px;
    margin-bottom: 15px;
    border-radius: 8px;
    box-shadow: 0 0 5px rgba(0,0,0,0.1);
}

audio {
    width: 100%;
}