:root {
  --bg: #f8f9fa;
  --surface: #ffffff;
  --border: #e2e8f0;
  --text: #1a202c;
  --text-secondary: #64748b;
  --accent: #2563eb;
  --accent-light: #eff6ff;
  --green: #16a34a;
  --red: #dc2626;
  --group-header-bg: #f1f5f9;
}
*, *::before, *::after { box-sizing: border-box; }
body {
  font-family: system-ui, -apple-system, 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  margin: 0;
  line-height: 1.6;
}
.container { max-width: 1100px; margin: 0 auto; padding: 0 20px; }
header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 16px 0;
}
header h1 {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 0;
}
header h1 a {
  color: var(--text);
  text-decoration: none;
}
header .subtitle {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 2px;
}
main { padding: 32px 0 64px; }

/* ─ WIP banner ─ */
.wip-banner {
  background: #dc2626;
  color: #fff;
  text-align: center;
  padding: 10px 16px;
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.1em;
}

/* ─ Index page ─ */
.selector-section {
  background: var(--surface);
  border-radius: 12px;
  padding: 32px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.06);
}
.selector-grid {
  display: grid;
  grid-template-columns: 1fr 60px 1fr;
  gap: 16px;
  align-items: start;
}
.selector-grid .vs {
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text-secondary);
  padding-top: 42px;
}
.selector-col label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text-secondary);
}
.search-input {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 0.95rem;
  outline: none;
  font-family: inherit;
}
.search-input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(37,99,235,0.1); }
.product-list {
  border: 1px solid var(--border);
  border-radius: 8px;
  max-height: 320px;
  overflow-y: auto;
  margin-top: 8px;
}
.product-item {
  padding: 10px 14px;
  cursor: pointer;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
  transition: background 0.1s;
}
.product-item:last-child { border-bottom: none; }
.product-item:hover:not(.disabled) { background: var(--accent-light); }
.product-item.selected {
  background: var(--accent);
  color: #fff;
}
.product-item.disabled {
  opacity: 0.35;
  cursor: not-allowed;
}
.product-item .brand { font-weight: 600; }
.product-item .meta {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-top: 2px;
}
.product-item.selected .meta { color: rgba(255,255,255,0.8); }
.compare-btn-wrap { text-align: center; margin-top: 24px; }
.compare-btn {
  display: inline-block;
  padding: 12px 40px;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  font-family: inherit;
  transition: background 0.15s;
}
.compare-btn:hover { background: #1d4ed8; }
.compare-btn:disabled { background: #94a3b8; cursor: not-allowed; }

/* ─ Comparison page ─ */
.compare-header {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 32px;
}
.product-card {
  background: var(--surface);
  border-radius: 12px;
  padding: 24px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.06);
}
.product-card h2 {
  font-size: 1.1rem;
  margin: 0 0 4px;
}
.product-card .cat {
  font-size: 0.85rem;
  color: var(--text-secondary);
}
.product-card .price {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent);
  margin-top: 8px;
}
.product-card .price.no-price { color: var(--text-secondary); font-size: 1rem; }
.product-card .ext-link {
  display: inline-block;
  margin-top: 12px;
  font-size: 0.85rem;
  color: var(--accent);
  text-decoration: none;
}
.product-card .ext-link:hover { text-decoration: underline; }

.spec-table-wrap {
  background: var(--surface);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 1px 3px rgba(0,0,0,0.06);
}
.spec-table { width: 100%; border-collapse: collapse; }
.spec-table .group-header td {
  background: var(--group-header-bg);
  font-weight: 700;
  font-size: 0.85rem;
  padding: 10px 16px;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}
.spec-table .group-header a {
  color: inherit;
  text-decoration: none;
}
.spec-table .group-header a:hover {
  text-decoration: underline;
}
.spec-table td {
  padding: 10px 16px;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
  vertical-align: top;
}
.spec-table tr:last-child td { border-bottom: none; }
.spec-table .label-col {
  width: 28%;
  font-weight: 500;
  color: var(--text-secondary);
  white-space: nowrap;
}
.spec-table .val-col { width: 36%; }
.spec-table .na { color: #cbd5e1; }
.spec-table .highlight { background: var(--accent-light); font-weight: 600; }

.back-link {
  display: inline-block;
  margin-bottom: 20px;
  font-size: 0.9rem;
  color: var(--accent);
  text-decoration: none;
}
.back-link:hover { text-decoration: underline; }

footer {
  text-align: center;
  padding: 32px 0;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

@media (max-width: 768px) {
  .selector-grid { grid-template-columns: 1fr; }
  .selector-grid .vs { padding-top: 0; }
  .compare-header { grid-template-columns: 1fr; }
  .spec-table .label-col { width: auto; }
  .spec-table .val-col { width: auto; }
}