/* ==========================================================================
   Buttons — shared across home, shop, product, cart & checkout so every
   "افزودن به سبد", "ثبت سفارش", "مشاهده محصول" etc. looks consistent
   instead of each page inventing its own button style.
   Usage: <button class="btn btn--primary">...</button>
   ========================================================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-5);
    border: 1px solid transparent;
    border-radius: var(--radius-pill);
    font-family: inherit;
    font-size: var(--text-sm);
    font-weight: 600;
    line-height: 1;
    cursor: pointer;
    white-space: nowrap;
    text-decoration: none;
    transition: background var(--transition-fast), color var(--transition-fast),
                border-color var(--transition-fast), transform var(--transition-fast),
                box-shadow var(--transition-fast);
}

.btn:active {
    transform: translateY(1px);
}

.btn:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

/* ---------- Variants ---------- */

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

.btn--primary:hover {
    background: var(--accent);
    border-color: var(--accent);
    color: #0A0A0A;
}

.btn--accent {
    background: var(--accent);
    color: #0A0A0A;
    border-color: var(--accent);
}

.btn--accent:hover {
    filter: brightness(1.08);
}

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

.btn--outline:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.btn--ghost {
    background: transparent;
    color: var(--text);
    border-color: transparent;
    padding-inline: var(--space-3);
}

.btn--ghost:hover {
    background: var(--border);
}

.btn--danger {
    background: transparent;
    color: #c0392b;
    border-color: #c0392b;
}

.btn--danger:hover {
    background: #c0392b;
    color: #fff;
}

/* ---------- Sizes ---------- */

.btn--sm {
    padding: var(--space-2) var(--space-4);
    font-size: var(--text-xs);
}

.btn--lg {
    padding: var(--space-4) var(--space-6);
    font-size: var(--text-base);
}

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

/* ---------- States ---------- */

.btn:disabled,
.btn[aria-disabled="true"] {
    opacity: .5;
    cursor: not-allowed;
    transform: none;
}

.btn.is-loading {
    color: transparent;
    pointer-events: none;
    position: relative;
}

.btn.is-loading::after {
    content: "";
    position: absolute;
    inset-inline-start: 50%;
    top: 50%;
    width: 16px;
    height: 16px;
    margin-inline-start: -8px;
    margin-top: -8px;
    border: 2px solid currentColor;
    border-top-color: transparent;
    border-radius: 50%;
    color: var(--bg);
    animation: btn-spin .7s linear infinite;
}

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

@media (prefers-reduced-motion: reduce) {
    .btn.is-loading::after {
        animation-duration: 1.4s;
    }
}