body {
    font-family: sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: #f0f0f0;
}

.container {
    text-align: center;
    background-color: #fff;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

.number-display {
    display: flex;
    justify-content: center;
    margin-bottom: 1rem;
}

.number-display span {
    display: inline-block;
    width: 40px;
    height: 40px;
    line-height: 40px;
    text-align: center;
    margin: 0 5px;
    border-radius: 50%;
    background-color: #eee;
    font-size: 1.2rem;
}

#generate-btn {
    padding: 0.5rem 1rem;
    font-size: 1rem;
    cursor: pointer;
    border: none;
    border-radius: 5px;
    background-color: #4CAF50;
    color: white;
}