/* ── PRODUCT PAGE ── */
.product-hero { padding: 48px 0 0; border-bottom: 1px solid var(--border); background: var(--black); }
.product-breadcrumb { font-size: 13px; color: var(--muted); margin-bottom: 1.5rem; display: flex; align-items: center; gap: 6px; }
.product-breadcrumb a { color: var(--muted); transition: color 0.15s; }
.product-breadcrumb a:hover { color: var(--text); }
.product-layout { display: grid; grid-template-columns: 1fr 400px; gap: 4rem; align-items: start; padding-bottom: 3rem; }
.product-status-row { display: flex; align-items: center; gap: 10px; margin-bottom: 1rem; }
.product-title { font-size: clamp(2rem,4vw,2.8rem); font-weight: 400; letter-spacing: -0.03em; line-height: 1.1; margin-bottom: 6px; color: var(--text); }
.product-scientific { font-size: 14px; color: var(--muted); font-style: italic; margin-bottom: 1.5rem; }
.product-cas-row { display: flex; align-items: center; gap: 1.5rem; margin-bottom: 1.5rem; flex-wrap: wrap; }
.product-cas { font-family: var(--mono); font-size: 12px; color: var(--sub); background: var(--surface); border: 1px solid var(--border); padding: 4px 10px; border-radius: var(--radius); }
.product-purity { display: flex; align-items: center; gap: 5px; font-size: 13px; color: var(--green); font-weight: 500; }
.product-short-desc { font-size: 15px; color: var(--sub); line-height: 1.75; max-width: 560px; margin-bottom: 2rem; padding-bottom: 2rem; border-bottom: 1px solid var(--border); }

/* Tabs */
.product-tabs { display: flex; gap: 0; border-bottom: 1px solid var(--border); margin-bottom: 1.5rem; }
.tab-btn { font-size: 13.5px; font-weight: 500; color: var(--muted); padding: 10px 20px; background: none; border: none; border-bottom: 2px solid transparent; margin-bottom: -1px; cursor: pointer; transition: color 0.15s, border-color 0.15s; }
.tab-btn:hover { color: var(--text); }
.tab-btn.active { color: var(--text); border-bottom-color: var(--text); }
.tab-panel { display: none; }
.tab-panel.active { display: block; }
.tab-panel h4 { font-size: 14px; font-weight: 600; margin-bottom: 0.6rem; color: var(--text); }
.tab-panel p { font-size: 14px; color: var(--sub); line-height: 1.8; margin-bottom: 1rem; }
.tab-panel ul { padding-left: 1.25rem; margin-bottom: 1rem; }
.tab-panel ul li { font-size: 14px; color: var(--sub); line-height: 1.8; margin-bottom: 4px; }
.spec-table { width: 100%; border-collapse: collapse; }
.spec-table tr { border-bottom: 1px solid var(--border); }
.spec-table tr:last-child { border-bottom: none; }
.spec-table td { padding: 10px 0; font-size: 13.5px; }
.spec-table td:first-child { color: var(--muted); width: 180px; font-weight: 500; }
.spec-table td:last-child { color: var(--text); font-family: var(--mono); font-size: 12.5px; }

/* Order card */
.order-card { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 24px; position: sticky; top: 80px; }
.order-card-title { font-size: 11px; font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); margin-bottom: 1rem; }
.size-options { display: flex; flex-direction: column; gap: 8px; margin-bottom: 1.5rem; }
.size-option { display: flex; align-items: center; justify-content: space-between; padding: 12px 14px; border: 1px solid var(--border); border-radius: var(--radius); cursor: pointer; transition: border-color 0.15s, background 0.15s; user-select: none; }
.size-option:hover { border-color: var(--border2); background: var(--surface2); }
.size-option.selected { border-color: rgba(255,255,255,0.4); background: var(--surface2); }
.size-option input[type=radio] { display: none; }
.size-label { font-size: 14px; font-weight: 500; color: var(--text); }
.size-sublabel { font-size: 11.5px; color: var(--muted); margin-top: 1px; }
.size-price { font-size: 15px; font-weight: 600; color: var(--text); }
.order-divider { border: none; border-top: 1px solid var(--border); margin: 1.25rem 0; }
.order-total-row { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 1.25rem; }
.order-total-label { font-size: 13px; color: var(--sub); }
.order-total-price { font-size: 1.4rem; font-weight: 600; color: var(--text); }
.btn-order-full { display: block; width: 100%; text-align: center; background: var(--text); color: var(--black); font-size: 14.5px; font-weight: 600; padding: 13px; border-radius: var(--radius); border: none; cursor: pointer; transition: opacity 0.15s; margin-bottom: 10px; }
.btn-order-full:hover { opacity: 0.88; }
.btn-inquire-full { display: block; width: 100%; text-align: center; background: transparent; color: var(--sub); font-size: 14px; font-weight: 500; padding: 11px; border-radius: var(--radius); border: 1px solid var(--border); cursor: pointer; transition: border-color 0.15s, color 0.15s; }
.btn-inquire-full:hover { border-color: var(--border2); color: var(--text); }
.order-trust { margin-top: 1.25rem; display: flex; flex-direction: column; gap: 7px; }
.order-trust-item { display: flex; align-items: center; gap: 8px; font-size: 12.5px; color: var(--sub); }
.order-trust-item i { color: var(--green); font-size: 14px; }

/* Preorder card */
.preorder-card { border-color: rgba(245,158,11,0.25); }
.preorder-card .btn-order-full { background: var(--text); color: var(--black); }
.preorder-note-card { background: var(--surface2); border: 1px solid rgba(245,158,11,0.2); border-radius: 8px; padding: 12px 14px; font-size: 12.5px; color: var(--sub); line-height: 1.6; margin-bottom: 1.25rem; }

/* Related */
.related-section { padding: 3rem 0 4rem; border-top: 1px solid var(--border); }
.related-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 1rem; margin-top: 1.5rem; }
.related-card { background: var(--surface); border: 1px solid var(--border); border-radius: 10px; padding: 18px; text-decoration: none; color: inherit; transition: box-shadow 0.15s, border-color 0.15s; display: block; }
.related-card:hover { box-shadow: var(--shadow); border-color: var(--border2); }
.related-card h4 { font-size: 14px; font-weight: 600; margin-bottom: 4px; color: var(--text); }
.related-card p { font-size: 12.5px; color: var(--sub); }
.related-card .rc-price { font-size: 14px; font-weight: 600; color: var(--text); margin-top: 10px; }