/* css/base.css — theme variables, reset, layout shell */
:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #6b7280;
  --border: #e5e7eb;
  --card: #f9fafb;
  --accent: #2563eb;
  --key-bg: #f3f4f6;
  --key-fg: #1f2937;
  --key-pressed: #2563eb;
  --key-pressed-fg: #ffffff;
  --key-tested: #22c55e;
  --key-tested-fg: #ffffff;
  --error: #ef4444;
}
[data-theme="dark"] {
  --bg: #0f172a;
  --fg: #e5e7eb;
  --muted: #94a3b8;
  --border: #334155;
  --card: #1e293b;
  --accent: #60a5fa;
  --key-bg: #334155;
  --key-fg: #e5e7eb;
  --key-pressed: #60a5fa;
  --key-pressed-fg: #0f172a;
  --key-tested: #22c55e;
  --key-tested-fg: #052e16;
  --error: #f87171;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--fg);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  min-height: 100vh;
}
.topbar {
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
  padding: 12px 16px; border-bottom: 1px solid var(--border);
  position: sticky; top: 0; background: var(--bg); z-index: 10;
}
.topbar .title { font-weight: 700; font-size: 18px; margin-right: auto; }
.topbar select, .topbar button {
  background: var(--card); color: var(--fg); border: 1px solid var(--border);
  border-radius: 8px; padding: 6px 10px; font-size: 14px; cursor: pointer;
}
.topbar button:hover, .topbar select:hover { border-color: var(--accent); }
.tabs { display: flex; gap: 4px; padding: 12px 16px 0; border-bottom: 1px solid var(--border); }
.tab-btn {
  background: none; border: none; border-bottom: 2px solid transparent;
  color: var(--muted); padding: 8px 14px; font-size: 15px; cursor: pointer;
}
.tab-btn.active { color: var(--accent); border-bottom-color: var(--accent); }
.tab-panel { display: none; padding: 20px 16px; }
.tab-panel.active { display: block; }
.panel-note { color: var(--muted); font-size: 13px; margin: 4px 0 16px; }