:root {
  --bg: #0f0d0a;
  --panel: #181410;
  --line: #2c251c;
  --fg: #f0e9df;
  --muted: #a8997f;
  --garlic: #e9d8a6;
  --good: #7bc47f;
  --bad: #e2845b;
  --accent: #c9a227;
}
* { box-sizing: border-box; }
body {
  margin: 0; background: radial-gradient(900px 500px at 80% -10%, #1c1710 0%, var(--bg) 60%);
  color: var(--fg); font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  -webkit-font-smoothing: antialiased; line-height: 1.5;
}
.masthead { text-align: center; padding: 56px 20px 28px; }
.logo { font-size: 40px; }
.masthead h1 { font-size: 38px; margin: 8px 0 6px; letter-spacing: -.02em; }
.sub { color: var(--muted); margin: 0; font-size: 16px; }
.src { display: inline-block; margin-top: 14px; color: var(--accent); text-decoration: none; font-weight: 600; }

main { max-width: 880px; margin: 0 auto; padding: 12px 20px 60px; display: grid; gap: 20px; }
.card { background: var(--panel); border: 1px solid var(--line); border-radius: 14px; padding: 22px; }
.card h2 { margin: 0 0 4px; font-size: 20px; }
.muted { color: var(--muted); font-size: 14px; }

.controls { display: flex; gap: 16px; flex-wrap: wrap; margin: 14px 0; }
.controls label, .field { display: grid; gap: 6px; font-size: 13px; color: var(--muted); }
select, input, textarea {
  font: inherit; color: var(--fg); background: #0f0c08; border: 1px solid var(--line);
  border-radius: 9px; padding: 9px 11px;
}
select:focus, input:focus, textarea:focus { outline: 2px solid var(--accent); outline-offset: -1px; }
.field { margin-top: 6px; }
textarea { width: 100%; resize: vertical; font-size: 15px; }

.io { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-top: 14px; }
@media (max-width: 680px) { .io { grid-template-columns: 1fr; } }
.io__label { font-size: 12px; color: var(--muted); margin-bottom: 6px; }
.io__box {
  margin: 0; padding: 12px; border-radius: 10px; background: #0c0a07; border: 1px solid var(--line);
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace; font-size: 13px;
  white-space: pre-wrap; word-break: break-all; min-height: 64px; overflow-x: auto;
}
.io__box--bad { color: var(--bad); border-color: #4a2f20; }
.io__box--good { color: var(--good); border-color: #244a26; word-break: normal; }
.roundtrip { font-size: 13px; margin: 12px 0 0; }
.roundtrip.ok { color: var(--good); }
.roundtrip.bad { color: var(--bad); }

.prose { font-size: 16.5px; }
.prose h2 { font-size: 22px; }
.prose h3 { font-size: 17px; margin-top: 22px; }
.prose blockquote {
  margin: 18px 0 0; padding: 12px 16px; border-left: 3px solid var(--accent);
  background: rgba(201,162,39,.08); color: var(--garlic); font-style: italic;
}
.link { background: none; border: none; color: var(--accent); font: inherit; cursor: pointer; padding: 0; text-decoration: underline; }

.usage code { color: var(--garlic); }
footer { text-align: center; color: var(--muted); font-size: 13px; padding: 30px 20px; }
footer a { color: var(--accent); }