.group-button .button:last-of-type {
    background-color: transparent;
    margin-left: 10px;
    transition: background .4s ease;
    color: rgba(var(--color-button), var(--alpha-button-background));
    border: 1px solid rgba(var(--color-button), var(--alpha-button-background));
}

.group-button .button:last-of-type:hover {
    background-color:  rgba(var(--color-button), var(--alpha-button-background));
    color: #fff; 
}