body {
    font-family: Arial, sans-serif;
    text-align: center;
    background-color: #1e1e1e;
    color: white;
}

.container {
    max-width: 600px;
    margin: 50px auto;
    padding: 20px;
    background-color: #2a2a2a;
    border-radius: 10px;
}

#price {
    font-size: 24px;
    margin: 10px 0;
}

#signal {
    font-size: 20px;
    font-weight: bold;
}

select {
    padding: 5px;
    font-size: 16px;
}

canvas {
    max-width: 100%;
}