.btn {
    display: inline-block;
    padding: 0.8rem 1.5rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    text-decoration: none;
    transition: background-color 0.3s ease;
}

.visible {
    opacity: 1;
    visibility: visible;
}

.hidden {
    opacity: 0;
    visibility: hidden;
}