:root {
  --bg: #0b0c0e;
  --bg-elev: #16181c;
  --border: #26292f;
  --text: #eaebee;
  --text-dim: #9a9ea6;
  --accent: #5eead4;
  --accent-dim: #2e5f57;
  --danger: #f87171;
  --radius: 10px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  line-height: 1.5;
}

.topbar {
  position: sticky; top: 0; z-index: 10;
  display: flex; justify-content: space-between; align-items: center;
  padding: 14px 16px;
  background: rgba(11,12,14,0.9);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid var(--border);
}
.logo { font-weight: 700; font-size: 18px; }
.logo span { color: var(--accent); }
nav { display: flex; gap: 16px; font-size: 14px; }
nav a { color: var(--text-dim); text-decoration: none; }
nav a:hover { color: var(--text); }

.hero { padding: 40px 16px 24px; text-align: center; }
.hero h1 { font-size: 26px; margin: 0 0 8px; }
.hero p { color: var(--text-dim); margin: 0; }

.section { padding: 24px 16px; max-width: 900px; margin: 0 auto; }
.section h2 { font-size: 20px; margin-bottom: 4px; }
.note, .hint { color: var(--text-dim); font-size: 13px; }

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 12px;
  margin-top: 12px;
}
.stock-card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 12px;
  text-align: center;
}
.stock-card canvas, .stock-card img { width: 100%; height: auto; border-radius: 6px; background: #fff; }
.stock-card h4 { margin: 8px 0 2px; font-size: 14px; }
.stock-card p { margin: 0; font-size: 12px; color: var(--text-dim); }
.stock-card button {
  margin-top: 8px; width: 100%;
  background: var(--accent-dim); color: var(--accent);
  border: none; border-radius: 8px; padding: 8px; font-size: 13px;
}

.builder { display: flex; flex-direction: column; gap: 20px; margin-top: 12px; }
@media (min-width: 700px) {
  .builder { flex-direction: row; }
  .builder-form, .builder-preview { flex: 1; }
}
.builder-form { display: flex; flex-direction: column; gap: 12px; }
.builder-form label { display: flex; flex-direction: column; gap: 4px; font-size: 13px; color: var(--text-dim); }
.builder-form input[type="text"], .builder-form textarea, .builder-form select {
  background: var(--bg-elev); border: 1px solid var(--border); color: var(--text);
  border-radius: 8px; padding: 10px; font-size: 15px;
}
.builder-form input[type="color"] { height: 40px; border: none; background: none; padding: 0; }
button {
  cursor: pointer; font-size: 15px; padding: 12px; border-radius: 8px;
  border: none; background: var(--accent); color: #06201b; font-weight: 600;
}
.builder-preview { display: flex; flex-direction: column; align-items: center; gap: 8px; }
#qrPreview { background: #fff; padding: 16px; border-radius: 10px; min-height: 200px; display: flex; align-items: center; justify-content: center; }
#qrPreview canvas, #qrPreview svg { max-width: 220px; }
button.secondary {
  background: none; border: 1px solid var(--border); color: var(--text-dim);
  font-weight: 500; width: auto; padding: 8px 14px; font-size: 13px;
}

.cart-items { min-height: 60px; display: flex; flex-direction: column; gap: 8px; margin: 12px 0; }
.cart-item {
  background: var(--bg-elev); border: 1px solid var(--border); border-radius: 8px;
  padding: 10px 12px; display: flex; justify-content: space-between; align-items: center; font-size: 14px;
}
.cart-item button { background: none; border: none; color: var(--danger); font-size: 13px; padding: 4px 8px; }
.checkout { width: 100%; }

.legal { padding: 24px 16px 48px; max-width: 900px; margin: 0 auto; border-top: 1px solid var(--border); }
.legal h3 { font-size: 15px; color: var(--text-dim); }
.legal p { font-size: 13px; color: var(--text-dim); }