:root {
    --button-back: hsl(240, 100%, 40%);
    font-size: 22px;
}

button {
    font-size: 1.5rem;
    padding: 1rem;
    border: none;
    border-radius: 1rem;
    background-color: var(--button-back);
    color: white;
    cursor: pointer;
}