/* ═══ APP SHELL ═══ */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  padding: 0 24px;
}

.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--fg);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.nav-brand span { color: var(--accent); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-link {
  font-size: 14px;
  font-weight: 500;
  color: var(--fg-muted);
  text-decoration: none;
  transition: color 0.15s;
}

.nav-link:hover { color: var(--fg); }

.nav-cart {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--fg);
  font-weight: 600;
}

.cart-badge {
  background: var(--accent);
  color: #fff;
  font-family: var(--font-display);
  font-size: 11px;
  font-weight: 700;
  min-width: 20px;
  height: 20px;
  border-radius: 100px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 5px;
}

#app-root {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 24px 80px;
  min-height: calc(100vh - 60px);
}

/* ═══ FITMENT SELECTOR ═══ */
.fitment-bar {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px 28px;
  margin-bottom: 32px;
}

.fitment-bar h3 {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 16px;
}

.fitment-selects {
  display: grid;
  grid-template-columns: repeat(4, 1fr) auto;
  gap: 12px;
  align-items: end;
}

.fitment-select-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.fitment-select-group label {
  font-size: 12px;
  font-weight: 500;
  color: var(--fg-muted);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.fitment-select-group select {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  color: var(--fg);
  padding: 10px 14px;
  border-radius: 8px;
  font-family: var(--font-body);
  font-size: 14px;
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg width='10' height='6' viewBox='0 0 10 6' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1 1L5 5L9 1' stroke='%23888' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 32px;
  transition: border-color 0.15s;
}

.fitment-select-group select:hover { border-color: #444; }
.fitment-select-group select:focus { outline: none; border-color: var(--accent); }
.fitment-select-group select:disabled { opacity: 0.4; cursor: not-allowed; }

.fitment-badge {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  background: rgba(255, 77, 0, 0.1);
  border: 1px solid rgba(255, 77, 0, 0.3);
  border-radius: 100px;
  font-size: 13px;
  color: var(--accent);
  font-weight: 600;
  white-space: nowrap;
}

.fitment-clear {
  background: none;
  border: 1px solid var(--border);
  color: var(--fg-muted);
  padding: 10px 16px;
  border-radius: 8px;
  cursor: pointer;
  font-family: var(--font-body);
  font-size: 13px;
  transition: all 0.15s;
  white-space: nowrap;
}

.fitment-clear:hover { border-color: var(--accent); color: var(--accent); }

/* ═══ CATALOG ═══ */
.catalog-layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 32px;
  align-items: start;
}

.catalog-sidebar h4 {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--fg-muted);
  margin-bottom: 12px;
}

.category-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.category-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 9px 14px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 14px;
  font-weight: 500;
  color: var(--fg-muted);
  transition: all 0.12s;
  border: 1px solid transparent;
}

.category-item:hover { background: var(--bg-card); color: var(--fg); }
.category-item.active { background: var(--bg-card); color: var(--fg); border-color: var(--border); }
.category-item.active span.cat-name { color: var(--accent); }

.category-count {
  font-size: 11px;
  color: var(--fg-muted);
  background: var(--bg-elevated);
  padding: 2px 7px;
  border-radius: 100px;
}

.catalog-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}

.catalog-header h2 {
  font-size: 22px;
  font-weight: 700;
}

.sort-select {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  color: var(--fg);
  padding: 8px 14px;
  border-radius: 8px;
  font-family: var(--font-body);
  font-size: 13px;
  cursor: pointer;
}

.parts-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

/* ═══ PART CARD ═══ */
.part-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  cursor: pointer;
  transition: border-color 0.15s, transform 0.15s;
  text-decoration: none;
  color: inherit;
  display: flex;
  flex-direction: column;
}

.part-card:hover { border-color: #444; transform: translateY(-2px); }

.part-card-img {
  width: 100%;
  aspect-ratio: 4/3;
  object-fit: cover;
  background: var(--bg-elevated);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 40px;
}

.part-card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.part-card-body {
  padding: 16px;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.part-card-brand {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--fg-muted);
}

.part-card-name {
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 600;
  line-height: 1.3;
  color: var(--fg);
}

.part-card-meta {
  font-size: 12px;
  color: var(--fg-muted);
  margin-top: auto;
}

.part-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  border-top: 1px solid var(--border);
  background: var(--bg-elevated);
}

.part-price {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--fg);
}

.part-price-sale { color: var(--accent); }
.part-price-original {
  font-size: 13px;
  color: var(--fg-muted);
  text-decoration: line-through;
  margin-left: 6px;
  font-weight: 400;
}

.fitment-badge-small {
  font-size: 11px;
  font-weight: 600;
  color: #22c55e;
  background: rgba(34, 197, 94, 0.1);
  border: 1px solid rgba(34, 197, 94, 0.2);
  padding: 3px 8px;
  border-radius: 100px;
}

.btn-add-cart {
  background: var(--accent);
  color: #fff;
  border: none;
  padding: 8px 14px;
  border-radius: 8px;
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: opacity 0.15s;
}

.btn-add-cart:hover { opacity: 0.85; }
.btn-add-cart:disabled { opacity: 0.5; cursor: not-allowed; }

/* ═══ PART DETAIL ═══ */
.part-detail-layout {
  display: grid;
  grid-template-columns: 1fr 420px;
  gap: 48px;
  align-items: start;
}

.part-detail-image {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  aspect-ratio: 4/3;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 80px;
  overflow: hidden;
}

.part-detail-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.part-detail-info { display: flex; flex-direction: column; gap: 20px; }

.part-detail-brand {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
}

.part-detail-name {
  font-size: clamp(22px, 3vw, 30px);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.2;
}

.part-detail-sku {
  font-size: 12px;
  color: var(--fg-muted);
}

.part-detail-price {
  font-family: var(--font-display);
  font-size: 32px;
  font-weight: 700;
  color: var(--fg);
}

.part-detail-price .original {
  font-size: 18px;
  color: var(--fg-muted);
  text-decoration: line-through;
  margin-left: 10px;
}

.part-detail-price.sale { color: var(--accent); }

.part-detail-desc {
  font-size: 16px;
  color: var(--fg-muted);
  line-height: 1.7;
  border-top: 1px solid var(--border);
  padding-top: 20px;
}

.part-detail-actions {
  display: flex;
  gap: 12px;
}

.btn-primary {
  flex: 1;
  background: var(--accent);
  color: #fff;
  border: none;
  padding: 14px 24px;
  border-radius: 10px;
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  transition: opacity 0.15s;
  text-align: center;
}

.btn-primary:hover { opacity: 0.85; }
.btn-primary:disabled { opacity: 0.5; cursor: not-allowed; }

.btn-secondary {
  padding: 14px 24px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--fg);
  border-radius: 10px;
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s;
  text-decoration: none;
  text-align: center;
}

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

.fitment-table {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.fitment-table h4 {
  padding: 14px 18px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--fg-muted);
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border);
}

.fitment-row {
  display: grid;
  grid-template-columns: 70px 1fr 1fr 1fr;
  gap: 12px;
  padding: 10px 18px;
  font-size: 13px;
  border-bottom: 1px solid var(--border);
}

.fitment-row:last-child { border-bottom: none; }
.fitment-row-header { background: var(--bg-card); color: var(--fg-muted); font-weight: 600; font-size: 11px; text-transform: uppercase; letter-spacing: 0.06em; }

/* ═══ CART ═══ */
.cart-layout {
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 32px;
  align-items: start;
}

.cart-empty {
  text-align: center;
  padding: 80px 0;
  color: var(--fg-muted);
}

.cart-empty h2 { font-size: 24px; margin-bottom: 16px; color: var(--fg); }
.cart-empty p { margin-bottom: 24px; }

.cart-item {
  display: grid;
  grid-template-columns: 80px 1fr auto;
  gap: 20px;
  align-items: center;
  padding: 20px 0;
  border-bottom: 1px solid var(--border);
}

.cart-item:last-child { border-bottom: none; }

.cart-item-img {
  width: 80px;
  height: 60px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  overflow: hidden;
  flex-shrink: 0;
}

.cart-item-img img { width: 100%; height: 100%; object-fit: cover; }

.cart-item-info h4 {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 4px;
}

.cart-item-info p {
  font-size: 12px;
  color: var(--fg-muted);
}

.cart-item-controls {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 10px;
}

.cart-item-price {
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
}

.qty-control {
  display: flex;
  align-items: center;
  gap: 0;
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
}

.qty-btn {
  background: var(--bg-elevated);
  border: none;
  color: var(--fg);
  width: 32px;
  height: 32px;
  cursor: pointer;
  font-size: 16px;
  transition: background 0.12s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.qty-btn:hover { background: var(--bg-card); }

.qty-display {
  padding: 0 14px;
  font-size: 14px;
  font-weight: 600;
  background: var(--bg);
  height: 32px;
  display: flex;
  align-items: center;
  border-left: 1px solid var(--border);
  border-right: 1px solid var(--border);
}

.cart-remove {
  background: none;
  border: none;
  color: var(--fg-muted);
  cursor: pointer;
  font-size: 12px;
  padding: 0;
  transition: color 0.12s;
}

.cart-remove:hover { color: #ef4444; }

.order-summary {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  position: sticky;
  top: 80px;
}

.order-summary h3 {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 20px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.summary-row {
  display: flex;
  justify-content: space-between;
  font-size: 14px;
  color: var(--fg-muted);
  margin-bottom: 10px;
}

.summary-row.total {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--fg);
  border-top: 1px solid var(--border);
  padding-top: 16px;
  margin-top: 6px;
}

.shipping-note {
  font-size: 12px;
  color: #22c55e;
  text-align: right;
  margin-top: -4px;
  margin-bottom: 10px;
}

/* ═══ CHECKOUT ═══ */
.checkout-layout {
  display: grid;
  grid-template-columns: 1fr 360px;
  gap: 40px;
  align-items: start;
}

.checkout-form h2 { font-size: 22px; margin-bottom: 24px; }

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 16px;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.form-group label {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--fg-muted);
}

.form-group input, .form-group select {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  color: var(--fg);
  padding: 12px 14px;
  border-radius: 8px;
  font-family: var(--font-body);
  font-size: 15px;
  transition: border-color 0.15s;
  width: 100%;
}

.form-group input:focus, .form-group select:focus {
  outline: none;
  border-color: var(--accent);
}

.form-section-title {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 24px 0 16px;
}

/* ═══ ORDER CONFIRMATION ═══ */
.order-confirm {
  max-width: 640px;
  margin: 0 auto;
  text-align: center;
  padding: 60px 0;
}

.order-confirm-icon {
  font-size: 60px;
  margin-bottom: 24px;
}

.order-confirm h1 {
  font-size: 32px;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.order-number-display {
  font-family: var(--font-display);
  font-size: 20px;
  color: var(--accent);
  font-weight: 700;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px 24px;
  display: inline-block;
  margin: 8px 0 24px;
}

.order-items-list {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-align: left;
  overflow: hidden;
  margin-top: 32px;
}

/* ═══ LOADING / EMPTY STATES ═══ */
.loading-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--fg-muted);
  font-size: 15px;
}

.loading-spinner {
  width: 28px;
  height: 28px;
  border: 2px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  margin: 0 auto 16px;
}

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

.empty-state {
  text-align: center;
  padding: 80px 20px;
  color: var(--fg-muted);
}

.empty-state-icon { font-size: 48px; margin-bottom: 20px; }
.empty-state h3 { font-size: 20px; color: var(--fg); margin-bottom: 10px; }

/* ═══ TOAST ═══ */
.toast {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 14px 20px;
  font-size: 14px;
  font-weight: 500;
  z-index: 999;
  transform: translateY(80px);
  opacity: 0;
  transition: all 0.25s ease;
  max-width: 340px;
}

.toast.show { transform: translateY(0); opacity: 1; }
.toast.success { border-color: #22c55e; color: #22c55e; }
.toast.error { border-color: #ef4444; color: #ef4444; }

/* ═══ PAGINATION ═══ */
.pagination {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-top: 32px;
}

.page-btn {
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--fg-muted);
  width: 36px;
  height: 36px;
  border-radius: 8px;
  cursor: pointer;
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 600;
  transition: all 0.12s;
}

.page-btn:hover { border-color: var(--accent); color: var(--accent); }
.page-btn.active { background: var(--accent); border-color: var(--accent); color: #fff; }

/* ═══ BREADCRUMB ═══ */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--fg-muted);
  margin-bottom: 28px;
}

.breadcrumb a { color: var(--fg-muted); text-decoration: none; }
.breadcrumb a:hover { color: var(--fg); }
.breadcrumb .sep { color: var(--border); }
.breadcrumb .current { color: var(--fg); font-weight: 500; }

/* ═══ RESPONSIVE ═══ */
@media (max-width: 900px) {
  .catalog-layout { grid-template-columns: 1fr; }
  .catalog-sidebar { display: flex; gap: 8px; flex-wrap: wrap; }
  .category-list { flex-direction: row; flex-wrap: wrap; }
  .parts-grid { grid-template-columns: repeat(2, 1fr); }
  .fitment-selects { grid-template-columns: 1fr 1fr; }
  .part-detail-layout { grid-template-columns: 1fr; }
  .cart-layout { grid-template-columns: 1fr; }
  .checkout-layout { grid-template-columns: 1fr; }
}

@media (max-width: 600px) {
  #app-root { padding: 20px 16px 60px; }
  .parts-grid { grid-template-columns: 1fr; }
  .fitment-selects { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
}