style.css

:root {
  --bg: #fff;
  --bg-muted: #f7f7f8;
  --border: #e4e4e7;
  --text: #18181b;
  --text-muted: #71717a;
  --accent: #2563eb;
  --accent-soft: #eff6ff;
}

* { box-sizing: border-box; }
body { margin: 0; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif; font-size: 14px; color: var(--text); background: var(--bg-muted); }
button { font: inherit; cursor: pointer; }

#toolbar {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 8px 12px;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}

.tb-btn {
  height: 30px;
  min-width: 30px;
  padding: 0 8px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 1px solid transparent;
  border-radius: 4px;
  color: var(--text);
}
.tb-btn:hover:not(:disabled) { background: var(--bg-muted); border-color: var(--border); }
.tb-btn.active { background: var(--accent-soft); color: var(--accent); }
.tb-btn:disabled { color: var(--text-muted); cursor: not-allowed; opacity: 0.5; }
.tb-btn.tb-btn-pill { padding: 0 12px; font-size: 13px; border-color: var(--border); margin-left: auto; }