:root {
  --bg: #0f172a;
  --surface: #1e293b;
  --text: #f8fafc;
  --muted: #94a3b8;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --danger: #ef4444;
  --success: #22c55e;
  --radius: 12px;
  --shadow: 0 10px 30px rgba(0,0,0,0.3);
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

.site-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  background: var(--surface);
  border-bottom: 1px solid #334155;
}

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--accent);
  text-decoration: none;
}

nav a {
  color: var(--muted);
  text-decoration: none;
  margin-left: 1.5rem;
  font-weight: 500;
}
nav a:hover { color: var(--text); }

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 2rem 1rem;
}

.hero {
  text-align: center;
  padding: 3rem 1rem;
}
.hero h1 { font-size: 2.5rem; margin: 0 0 0.5rem; }
.hero p { color: var(--muted); font-size: 1.1rem; max-width: 600px; margin: 0 auto 1.5rem; }

.search-row {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  max-width: 600px;
  margin: 0 auto;
}
.search-row input {
  flex: 1;
  padding: 0.75rem 1rem;
  border: 1px solid #334155;
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  font-size: 1rem;
}

.btn {
  display: inline-block;
  padding: 0.65rem 1.25rem;
  border: none;
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
}
.btn:hover { background: #334155; }
.btn-primary {
  background: var(--accent);
  color: white;
}
.btn-primary:hover { background: var(--accent-hover); }

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.card {
  background: var(--surface);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: transform 0.15s;
}
.card:hover { transform: translateY(-4px); }
.card img { width: 100%; height: 180px; object-fit: cover; background: #0f172a; }
.card-body { padding: 1rem; }
.card h3 { margin: 0 0 0.25rem; font-size: 1.1rem; }
.card h3 a { color: var(--text); text-decoration: none; }
.card h3 a:hover { color: var(--accent); }
.card .part-number { color: var(--muted); font-size: 0.85rem; margin: 0 0 0.5rem; }
.card .fits { color: var(--muted); font-size: 0.85rem; margin: 0 0 0.75rem; }
.card .price { font-size: 1.25rem; font-weight: 700; color: var(--success); margin: 0 0 0.75rem; }

.tag-board {
  display: grid;
  gap: 1rem;
}
.demand-tag {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 1rem;
  border-left: 4px solid var(--accent);
}
.tag-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.5rem;
}
.tag-budget {
  background: var(--bg);
  color: var(--success);
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  font-weight: 700;
  font-size: 0.85rem;
}
.tag-meta { color: var(--muted); font-size: 0.8rem; margin: 0.5rem 0 0; }
.tag-tags { margin-top: 0.5rem; }
.tag {
  display: inline-block;
  background: #334155;
  color: var(--muted);
  padding: 0.2rem 0.5rem;
  border-radius: 999px;
  font-size: 0.75rem;
  margin-right: 0.35rem;
}

.form-section {
  max-width: 600px;
  margin: 3rem auto 0;
  background: var(--surface);
  padding: 1.5rem;
  border-radius: var(--radius);
}
.form-section h2 { margin-top: 0; }
form input, form textarea {
  width: 100%;
  padding: 0.75rem;
  margin-bottom: 0.75rem;
  border: 1px solid #334155;
  border-radius: var(--radius);
  background: var(--bg);
  color: var(--text);
  font-size: 1rem;
}
form textarea { min-height: 100px; resize: vertical; }

.part-detail { padding-top: 2rem; }
.part-card-detail {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  background: var(--surface);
  padding: 2rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.part-card-detail img { width: 100%; border-radius: var(--radius); }
.gallery { display: grid; grid-template-columns: repeat(auto-fill, minmax(120px, 1fr)); gap: 0.5rem; margin-top: 1rem; }
.gallery img { width: 100%; height: 120px; object-fit: cover; border-radius: 8px; border: 1px solid #334155; cursor: pointer; }
.gallery-main { width: 100%; max-height: 400px; object-fit: contain; border-radius: var(--radius); margin-bottom: 0.5rem; background: #0f172a; }
.part-info h1 { margin-top: 0; }
.part-info .price { font-size: 2rem; font-weight: 800; color: var(--success); margin: 1rem 0; }
.part-info .stock { color: var(--muted); }
.buy-form { margin-top: 1.5rem; }
.buy-form label { margin-right: 1rem; }
.buy-form input {
  width: 60px;
  padding: 0.5rem;
  border: 1px solid #334155;
  border-radius: 6px;
  background: var(--bg);
  color: var(--text);
}

.loading, .empty { color: var(--muted); text-align: center; padding: 2rem; }

.site-footer {
  text-align: center;
  padding: 2rem;
  color: var(--muted);
  border-top: 1px solid #334155;
  margin-top: 3rem;
}

@media (max-width: 700px) {
  .site-header { flex-direction: column; gap: 0.75rem; }
  .part-card-detail { grid-template-columns: 1fr; }
  .hero h1 { font-size: 1.8rem; }
}