:root {
  color-scheme: light dark;
  --bg: #f4f5f7; --panel: #fff; --ink: #1f2328; --soft: #57606a;
  --line: rgba(31, 35, 40, 0.15); --accent: #0969da; --good: #1a7f37; --bad: #cf222e;
  --mono: "SF Mono", Menlo, Consolas, monospace;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #0d1117; --panel: #161b22; --ink: #e6edf3; --soft: #9da7b3;
    --line: rgba(230, 237, 243, 0.15); --accent: #4493f8; --good: #3fb950; --bad: #f85149; }
}
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; background: var(--bg); color: var(--ink);
  font: 15px/1.5 system-ui, -apple-system, "Segoe UI", sans-serif; }
main { max-width: 960px; margin: 0 auto; padding: 24px 16px; }
main.narrow { max-width: 440px; }
h1 { margin: 0 0 4px; font-size: 1.5rem; }
h2 { margin: 24px 0 8px; font-size: 1.1rem; }
a { color: var(--accent); }
.sub { color: var(--soft); margin: 0 0 16px; }
.card { background: var(--panel); border: 1px solid var(--line); border-radius: 12px; padding: 20px; }
.top { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; }
.stack { display: flex; flex-direction: column; gap: 12px; }
label { display: flex; flex-direction: column; gap: 4px; color: var(--soft); }
input { font: inherit; padding: 8px 10px; border: 1px solid var(--line); border-radius: 8px; background: var(--bg); color: var(--ink); }
button { font: inherit; padding: 8px 14px; border: 1px solid var(--line); border-radius: 8px;
  background: var(--panel); color: var(--ink); cursor: pointer; }
button:hover { border-color: var(--accent); }
button:disabled { opacity: 0.6; cursor: default; }
table { width: 100%; border-collapse: collapse; }
th, td { text-align: left; padding: 8px; border-bottom: 1px solid var(--line); vertical-align: top; }
.ok { color: var(--good); }
.bad { color: var(--bad); }
.mono, pre { font-family: var(--mono); font-size: 13px; }
pre { background: var(--bg); border: 1px solid var(--line); border-radius: 8px; padding: 12px;
  overflow-x: auto; white-space: pre-wrap; word-break: break-word; max-height: 70vh; }