body {
    background: linear-gradient(to bottom right, #d1f5e0, #baf3e3);
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

.container {
    background: white;
    padding: 30px;
    border-radius: 20px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.15);
    text-align: center;
    width: 350px;
}

h1 {
    margin-bottom: 20px;
    color: #145a32;
}

.btn {
    background: #1abc9c;
    color: white;
    border: none;
    padding: 15px;
    font-size: 18px;
    border-radius: 10px;
    cursor: pointer;
    width: 120px;
    margin: 5px;
}

.btn.small {
    width: 60px;
    padding: 10px;
}

.btn:hover {
    background: #17a589;
}

.slider-group {
    margin-top: 20px;
}

#progressBar {
    width: 100%;
}

.time {
    display: flex;
    justify-content: space-between;
    margin-top: 5px;
    color: #444;
}

.volume-group {
    margin-top: 20px;
    font-size: 20px;
}