/* product.css */

.back-link {
    display: inline-flex;
    margin-bottom: 18px;
    color: #374151;
    text-decoration: none;
    font-weight: 700;
}

.product-page {
    max-width: 1100px;
}

.product-hero {
    background: white;
    border-radius: 22px;
    padding: 24px;
    margin-bottom: 20px;
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 28px;
    box-shadow: 0 4px 18px rgba(0, 0, 0, .05);
}

.product-detail-image {
    width: 100%;
    height: 280px;
    object-fit: contain;
    border: 1px solid #eee;
    border-radius: 18px;
    padding: 16px;
    background: white;
}

.product-detail-title {
    margin: 0 0 18px;
    font-size: 28px;
    line-height: 1.35;
}

.product-price-main {
    margin-bottom: 18px;
}

.price-label,
.stat-label {
    color: #6b7280;
    font-size: 14px;
    font-weight: 700;
    margin-bottom: 4px;
}

.price-value {
    font-size: 44px;
    font-weight: 800;
    color: #dc2626;
}

.product-stat-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
    margin-bottom: 18px;
}

.stat-card {
    background: #f5f7fb;
    border-radius: 16px;
    padding: 14px;
}

.stat-value {
    font-size: 20px;
    font-weight: 800;
    color: #111827;
}

.primary-action {
    background: #111827;
    color: white;
}

.product-section-title {
    font-size: 20px;
    font-weight: 800;
    margin-bottom: 14px;
}

.product-detail-chart {
    width: 100%;
    height: 460px;
}

.chart {
    width: 100%;
    height: 420px;
    margin-top: 12px;
}

.price-change-list {
    display: grid;
    gap: 10px;
    max-height: 420px;
    overflow-y: auto;
    padding-right: 8px;
}

.price-change-item {
    display: flex;
    justify-content: space-between;
    gap: 14px;
    padding: 12px 0;
    border-bottom: 1px solid #e5e7eb;
    font-weight: 700;
}

.price-change-down {
    color: #dc2626;
}

.price-change-up {
    color: #2563eb;
}

.price-history-note {
    margin: 4px 0 8px;
    color: #64748b;
    font-size: 12px;
    line-height: 1.45;
}

.product-note {
    color: #6b7280;
    line-height: 1.8;
    font-size: 14px;
}

.scan-time-value {
    font-size: 18px;
    color: #475569;
    white-space: nowrap;
}

.stat-scan-today {
    background: #f0fdf4;
    border-color: #bbf7d0;
}

.stat-scan-today .stat-label {
    color: #15803d;
}

.stat-scan-today .stat-value {
    color: #166534;
}

.stat-scan-old {
    background: #fffbeb;
    border-color: #fde68a;
}

.stat-scan-old .stat-label {
    color: #b45309;
}

.stat-scan-old .stat-value {
    color: #92400e;
}

@media(max-width:768px) {
    .product-hero {
        grid-template-columns: 1fr;
    }

    .product-detail-title {
        font-size: 22px;
    }

    .price-value {
        font-size: 36px;
    }

    .product-stat-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .product-detail-chart {
        height: 360px;
    }
}