.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: 15px 30px;
    font-family: var(--font-mono);
    font-size: 0.82rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    border-radius: var(--radius);
    cursor: pointer;
    border: 1px solid transparent;
    text-align: center;
    transition: transform var(--transition), background var(--transition), border-color var(--transition), color var(--transition);
    position: relative;
}

.btn-primary {
    background-color: var(--gold);
    color: var(--bg-base);
}

.btn-primary:hover:not(:disabled) {
    background-color: var(--gold-bright);
    transform: translateY(-2px);
}

.btn-outline {
    border-color: var(--silver);
    color: var(--text-primary);
    background-color: transparent;
}

.btn-outline:hover:not(:disabled) {
    border-color: var(--gold-bright);
    color: var(--gold-bright);
}

.btn-whatsapp {
    background-color: var(--whatsapp);
    color: var(--whatsapp-dark);
}

.btn-whatsapp:hover:not(:disabled) {
    background-color: var(--whatsapp-bright);
    transform: translateY(-2px);
}

.btn-block {
    display: flex;
    width: 100%;
}

.btn:disabled,
.btn[aria-busy="true"] {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important;
    pointer-events: none;
}

.btn[aria-busy="true"]::after {
    content: "";
    width: 14px;
    height: 14px;
    border: 2px solid currentColor;
    border-top-color: transparent;
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
    margin-left: var(--space-2);
}

@keyframes spin { to { transform: rotate(360deg); } }