:root {
    --gold: #bfa15f;
    --dark-gold: #a68a4d;
    --dark: #1a2226;
    --light-bg: #ffffff;
    --text-muted: #6c757d;
}

/* استایل دکمه بازگشت */
.btn-back-top {
    position: absolute;
    top: 150px;
    left: 20px;
    width: 45px;
    height: 45px;
    background-color: var(--light-bg);
    border: 1px solid #eee;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--dark);
    text-decoration: none;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
    z-index: 1050;
}

    .btn-back-top:hover {
        background-color: var(--gold);
        color: white;
        border-color: var(--gold);
        transform: scale(1.1);
    }

.product-image-box {
    background-color: var(--light-bg);
    border-radius: 20px;
    padding: 2rem;
    text-align: center;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.03);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}

    .product-image-box img {
        max-width: 100%;
        max-height: 400px;
        object-fit: contain;
    }

.product-title {
    color: var(--dark);
    font-weight: 700;
    font-size: 1.75rem;
    line-height: 1.5;
    margin-bottom: 1rem;
}

.badge-stock {
    background-color: rgba(191, 161, 95, 0.1);
    color: var(--gold);
    padding: 8px 15px;
    border-radius: 8px;
    font-weight: 500;
    font-size: 0.9rem;
}

.price-box {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--dark);
    margin: 1.5rem 0;
    display: flex;
    align-items: center;
    gap: 10px;
}

    .price-box span {
        font-size: 1rem;
        color: var(--text-muted);
        font-weight: 400;
    }

.variant-options {
    display: flex;
    gap: 10px;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.btn-variant {
    border: 1px solid #dee2e6;
    background-color: transparent;
    color: var(--dark);
    border-radius: 10px;
    padding: 8px 16px;
    font-weight: 500;
    transition: all 0.2s;
}

.btn-check:checked + .btn-variant {
    border-color: var(--gold);
    background-color: rgba(191, 161, 95, 0.05);
    color: var(--dark);
}

.key-features {
    background-color: var(--light-bg);
    border-radius: 16px;
    padding: 1.5rem;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.03);
    margin-bottom: 1.5rem;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 15px;
}

.feature-icon {
    width: 40px;
    height: 40px;
    background-color: rgba(26, 34, 38, 0.05);
    color: var(--dark);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
}

.feature-text div:first-child {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.feature-text div:last-child {
    font-weight: 600;
    color: var(--dark);
    font-size: 0.95rem;
}

.btn-add-to-cart {
    background-color: var(--dark);
    color: var(--gold);
    border: none;
    border-radius: 12px;
    padding: 1rem 2rem;
    font-size: 1.1rem;
    font-weight: 600;
    width: 100%;
    transition: all 0.3s;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
    text-decoration: none;
}

    .btn-add-to-cart:hover {
        background-color: var(--gold);
        color: var(--dark);
    }

.action-bar {
    background-color: var(--light-bg);
    border-radius: 16px;
    padding: 1.5rem;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.03);
}

.custom-tabs .nav-link {
    color: var(--text-muted);
    font-weight: 500;
    border: none;
    border-bottom: 2px solid transparent;
    padding: 1rem 1.5rem;
}

    .custom-tabs .nav-link.active {
        color: var(--dark);
        border-bottom: 2px solid var(--gold);
        background: transparent;
    }

.tab-content-box {
    background-color: var(--light-bg);
    border-radius: 0 0 16px 16px;
    padding: 2rem;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.03);
    line-height: 1.8;
    color: #495057;
}

@media (max-width: 767.98px) {
    body {
        padding-bottom: 100px;
    }

    .desktop-action-bar {
        display: none !important;
    }

    .mobile-action-bar {
        display: flex !important;
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;
        background-color: var(--light-bg);
        padding: 15px 20px;
        box-shadow: 0 -4px 20px rgba(0, 0, 0, 0.08);
        z-index: 1030;
        align-items: center;
        justify-content: space-between;
        border-radius: 20px 20px 0 0;
    }

    .mobile-price {
        display: flex;
        flex-direction: column;
    }

        .mobile-price span:last-child {
            font-weight: 700;
            font-size: 1.2rem;
        }

    .mobile-action-bar .btn-add-to-cart {
        width: auto;
        padding: 0.7rem 1.5rem;
        font-size: 1rem;
    }

    .btn-back-top {
        top: 10px;
        left: 10px;
        width: 40px;
        height: 40px;
    }
}

@media (min-width: 768px) {
    .mobile-action-bar {
        display: none !important;
    }
}










.installment-modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(15, 23, 42, 0.5);
    display: none;
    align-items: center;
    justify-content: center;
    padding: 16px;
    z-index: 1200;
}

    .installment-modal-overlay.is-open {
        display: flex;
    }

.installment-modal {
    width: 100%;
    max-width: 420px;
    background: #fff;
    border-radius: 24px;
    padding: 22px 18px 18px;
    position: relative;
    box-shadow: 0 20px 60px rgba(15, 23, 42, 0.18);
    animation: installmentModalFade 0.2s ease;
}

.installment-modal-close {
    position: absolute;
    top: 12px;
    left: 12px;
    width: 36px;
    height: 36px;
    border: 0;
    border-radius: 50%;
    background: #f3f4f6;
    color: #111827;
    font-size: 24px;
    line-height: 1;
    cursor: pointer;
}

.installment-modal-header {
    text-align: center;
    padding-top: 8px;
}

.installment-modal-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 12px;
    border-radius: 20px;
    background: rgba(202, 166, 75, 0.14);
    color: #caa64b;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
}

.installment-modal-title {
    margin: 0;
    font-size: 20px;
    font-weight: 800;
    color: #111827;
}

.installment-modal-subtitle {
    margin: 8px 0 0;
    font-size: 13px;
    color: #6b7280;
    line-height: 1.8;
}

.installment-modal-body {
    margin-top: 18px;
}

.installment-modal-list {
    margin: 0;
    padding: 0 18px 0 0;
    color: #374151;
    font-size: 14px;
    line-height: 2;
}

.installment-modal-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    margin-top: 22px;
}

.installment-modal-continue,
.installment-modal-cancel {
    min-height: 48px;
    border-radius: 16px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    font-size: 14px;
    font-weight: 700;
}

.installment-modal-continue {
    background: #caa64b;
    color: #fff;
}

.installment-modal-cancel {
    border: 1px solid #e5e7eb;
    background: #fff;
    color: #374151;
    cursor: pointer;
}

body.modal-open {
    overflow: hidden;
}

@keyframes installmentModalFade {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (max-width: 576px) {
    .installment-modal-overlay {
        padding: 12px;
        align-items: flex-end;
    }

    .installment-modal {
        max-width: 100%;
        border-radius: 24px 24px 16px 16px;
        padding: 20px 16px 16px;
    }

    .installment-modal-actions {
        grid-template-columns: 1fr;
    }
}