/* === Custom Properties === */
:root {
  --color-accent: #d32f2f;
  --color-accent-light: #ff6659;
  --color-bg: #f5f5f5;
  --color-surface: #ffffff;
  --color-text: #212121;
  --color-text-secondary: #666666;
  --color-border: #e0e0e0;
  --color-link: #1a73e8;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --font-stack: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --sidebar-width: 280px;
}

/* === Reset & Base === */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-stack);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.5;
  min-height: 100vh;
}

/* === Header === */
.site-header {
  background: var(--color-surface);
  padding: 20px 24px;
  border-bottom: 1px solid var(--color-border);
  text-align: center;
}

.site-header h1 {
  font-size: 1.6rem;
  font-weight: 700;
}

.update-button {
  display: inline-block;
  margin-top: 12px;
  padding: 8px 16px;
  background-color: var(--color-link);
  color: white;
  text-decoration: none;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-weight: 600;
  transition: background-color 0.2s;
}

.update-button:hover {
  background-color: #1a73e8;
}

.scraped-date {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  margin-top: 4px;
}

/* === Metrics Bar === */
.metrics-bar {
  display: flex;
  justify-content: center;
  gap: 24px;
  padding: 16px 24px;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  flex-wrap: wrap;
}

.metric {
  display: flex;
  flex-direction: column;
  align-items: center;
  min-width: 120px;
}

.metric-value {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-accent);
}

.metric-label {
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* === Main Layout === */
.main-layout {
  display: flex;
  max-width: 1400px;
  margin: 0 auto;
  padding: 20px;
  gap: 24px;
}

/* === Filter Panel === */
.filter-panel {
  width: var(--sidebar-width);
  flex-shrink: 0;
  background: var(--color-surface);
  border-radius: var(--radius-md);
  padding: 20px;
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 20px;
  align-self: flex-start;
  max-height: calc(100vh - 40px);
  overflow-y: auto;
}

.filter-panel-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.filter-panel-header h2 {
  font-size: 1.1rem;
  font-weight: 700;
}

.filter-close-btn {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--color-text-secondary);
  padding: 0 4px;
}

.filter-section {
  margin-bottom: 20px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--color-border);
}

.filter-section:last-child {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

.filter-section h3 {
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.filter-section label {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
}

.filter-section label strong {
  color: var(--color-accent);
}

.checkbox-label {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 4px 0;
  cursor: pointer;
  font-size: 0.85rem;
  color: var(--color-text);
}

.checkbox-label input[type="checkbox"] {
  accent-color: var(--color-accent);
  width: 16px;
  height: 16px;
}

/* Range slider */
input[type="range"] {
  width: 100%;
  margin: 8px 0;
  accent-color: var(--color-accent);
}

/* Select */
select {
  width: 100%;
  padding: 8px 10px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-family: var(--font-stack);
  background: var(--color-surface);
  margin-top: 6px;
}

/* Brand search */
.brand-search {
  width: 100%;
  padding: 7px 10px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-family: var(--font-stack);
  margin-bottom: 8px;
}

.brand-search:focus {
  outline: none;
  border-color: var(--color-accent);
}

.brand-list {
  max-height: 200px;
  overflow-y: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 4px;
}

.brand-list .checkbox-label {
  padding: 3px 6px;
  font-size: 0.82rem;
}

.brand-list .checkbox-label.hidden {
  display: none;
}

/* Dual range slider */
.price-range-display {
  display: flex;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  margin-bottom: 4px;
}

.dual-range {
  position: relative;
  height: 36px;
}

.dual-range input[type="range"] {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  pointer-events: none;
  -webkit-appearance: none;
  appearance: none;
  background: transparent;
  margin: 0;
}

.dual-range input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--color-accent);
  border: 2px solid var(--color-surface);
  box-shadow: var(--shadow-sm);
  pointer-events: auto;
  cursor: pointer;
}

.dual-range input[type="range"]::-moz-range-thumb {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--color-accent);
  border: 2px solid var(--color-surface);
  box-shadow: var(--shadow-sm);
  pointer-events: auto;
  cursor: pointer;
}

.dual-range input[type="range"]::-webkit-slider-runnable-track {
  height: 4px;
  background: var(--color-border);
  border-radius: 2px;
}

.dual-range input[type="range"]::-moz-range-track {
  height: 4px;
  background: var(--color-border);
  border-radius: 2px;
}

/* === Filter overlay (mobile) === */
.filter-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
  z-index: 90;
}

.filter-overlay.active {
  display: block;
}

/* === Filter toggle button (mobile) === */
.filter-toggle-btn {
  display: none;
  padding: 10px 20px;
  background: var(--color-accent);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  margin-bottom: 16px;
  font-family: var(--font-stack);
}

.filter-toggle-btn:hover {
  background: var(--color-accent-light);
}

/* === Content Area === */
.content-area {
  flex: 1;
  min-width: 0;
}

.results-status {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
  margin-bottom: 16px;
}

/* === Loader === */
.loader {
  border: 4px solid var(--color-bg);
  border-top: 4px solid var(--color-accent);
  border-radius: 50%;
  width: 40px;
  height: 40px;
  animation: spin 1s linear infinite;
  margin: 40px auto;
  display: none; /* Initially hidden */
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

/* === Product Grid === */
.product-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.product-grid .empty-state {
  grid-column: 1 / -1;
  text-align: center;
  padding: 60px 20px;
  color: var(--color-text-secondary);
  font-size: 1rem;
}

/* === Product Card === */
.product-card {
  background: var(--color-surface);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  display: flex;
  flex-direction: column;
}

.product-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.card-image {
  width: 100%;
  aspect-ratio: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #fafafa;
  padding: 12px;
}

.card-image img {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}

.card-body {
  padding: 12px 14px 14px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.card-name {
  font-size: 0.85rem;
  font-weight: 600;
  line-height: 1.35;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  margin-bottom: 4px;
  min-height: 2.3em;
}

.card-brand {
  font-size: 0.78rem;
  color: var(--color-text-secondary);
  margin-bottom: 8px;
}

.card-pricing {
  margin-top: auto;
  margin-bottom: 8px;
}

.card-original-price {
  text-decoration: line-through;
  color: #999;
  font-size: 0.8rem;
  margin-right: 6px;
}

.card-sale-price {
  color: var(--color-accent);
  font-weight: 700;
  font-size: 1.15rem;
}

.card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 6px;
}

.discount-badge {
  background: var(--color-accent);
  color: #fff;
  padding: 2px 10px;
  border-radius: 12px;
  font-size: 0.75rem;
  font-weight: 700;
}

.stock-badge {
  font-size: 0.72rem;
  padding: 2px 8px;
  border-radius: 10px;
  font-weight: 600;
}

.stock-badge.in-stock {
  background: #e8f5e9;
  color: #2e7d32;
}

.stock-badge.out-of-stock {
  background: #fce4ec;
  color: #c62828;
}

.card-link {
  display: block;
  text-align: center;
  padding: 8px;
  font-size: 0.8rem;
  color: var(--color-link);
  text-decoration: none;
  border-top: 1px solid var(--color-border);
}

.card-link:hover {
  background: #f0f4ff;
}

/* === Pagination === */
.pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 16px;
  margin-top: 24px;
  padding: 16px 0;
}

.page-btn {
  padding: 8px 20px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  font-size: 0.85rem;
  font-family: var(--font-stack);
  cursor: pointer;
  transition: background 0.15s;
}

.page-btn:hover:not(:disabled) {
  background: var(--color-bg);
}

.page-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.page-indicator {
  font-size: 0.85rem;
  color: var(--color-text-secondary);
}

/* === Footer === */
.site-footer {
  text-align: center;
  padding: 20px 24px;
  border-top: 1px solid var(--color-border);
  margin-top: 24px;
}

.site-footer p {
  font-size: 0.78rem;
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

.site-footer a {
  color: var(--color-link);
}

/* === Responsive: Tablet === */
@media (max-width: 1024px) {
  .product-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* === Responsive: Mobile === */
@media (max-width: 768px) {
  .site-header h1 {
    font-size: 1.25rem;
  }

  .metrics-bar {
    gap: 12px;
    padding: 12px 16px;
  }

  .metric-value {
    font-size: 1.2rem;
  }

  .main-layout {
    padding: 12px;
  }

  .product-grid {
    grid-template-columns: 1fr;
  }

  .filter-toggle-btn {
    display: block;
  }

  .filter-panel {
    position: fixed;
    top: 0;
    left: -100%;
    width: 85%;
    max-width: 320px;
    height: 100vh;
    max-height: 100vh;
    border-radius: 0;
    z-index: 100;
    transition: left 0.3s ease;
    padding: 20px;
  }

  .filter-panel.open {
    left: 0;
  }

  .filter-close-btn {
    display: block;
  }
}