:root {
  --bg: #f6f7f9; --panel: #ffffff; --ink: #1c2430; --muted: #6b7684;
  --line: #d9dee5; --accent: #2b6cb0; --ok: #1f7a3a; --bad: #b3261e; --code: #0f172a;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--ink); }
header { padding: 14px 20px; border-bottom: 1px solid var(--line); background: var(--panel);
         display: flex; gap: 16px; align-items: baseline; }
header h1 { font-size: 18px; margin: 0; }
header nav a { margin-right: 12px; color: var(--accent); text-decoration: none; }
header .status { margin-left: auto; color: var(--muted); font-size: 13px; }
.layout { display: grid; grid-template-columns: 260px 1fr; min-height: calc(100vh - 50px); }
aside { border-right: 1px solid var(--line); background: var(--panel); overflow: auto; }
aside ul { list-style: none; margin: 0; padding: 8px 0; }
aside li { padding: 6px 16px; cursor: pointer; font-family: ui-monospace, Consolas, monospace; font-size: 13px; }
aside li:hover { background: #eef2f7; }
aside li.active { background: #e2ecf8; color: var(--accent); }
main { padding: 16px 20px; display: flex; flex-direction: column; gap: 12px; }
.toolbar { display: flex; gap: 8px; align-items: center; }
button { padding: 6px 14px; border: 1px solid var(--line); background: var(--panel); border-radius: 4px;
         cursor: pointer; font-size: 13px; }
button.primary { background: var(--accent); color: white; border-color: var(--accent); }
button:disabled { opacity: 0.5; cursor: default; }
.meta { color: var(--muted); font-size: 13px; }
pre { margin: 0; padding: 12px; background: var(--code); color: #e6edf3; border-radius: 6px;
      font-family: ui-monospace, Consolas, monospace; font-size: 13px; white-space: pre-wrap;
      min-height: 120px; max-height: 45vh; overflow: auto; }
pre.stderr { background: #3a0f0f; color: #ffd6d6; min-height: 0; }
pre.source { background: #f3f5f8; color: var(--ink); max-height: 50vh; }
details summary { cursor: pointer; color: var(--muted); font-size: 13px; }
table { border-collapse: collapse; width: 100%; font-size: 13px; background: var(--panel); }
th, td { border-bottom: 1px solid var(--line); padding: 6px 10px; text-align: left; }
th { background: #eef2f7; }
td.num { text-align: right; font-variant-numeric: tabular-nums; }
.ok { color: var(--ok); font-weight: 600; }
.bad { color: var(--bad); font-weight: 600; }
.skip { color: var(--muted); }
input[type=number] { width: 60px; padding: 4px; }