:root {
  color-scheme: light dark;
  --bg: #fbfaf8;
  --surface: #ffffff;
  --text: #1a1a18;
  --muted: #5c5b57;
  --line: #e2e0da;
  --accent: #1c5f4a;
  --pass: #1c6b3f;
  --fail: #a32626;
  --fail-bg: #fdf0ef;
  --pass-bg: #f0f7f2;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #16171a;
    --surface: #1e1f23;
    --text: #ececea;
    --muted: #9c9b96;
    --line: #32343a;
    --accent: #6dc4a4;
    --pass: #6dc4a4;
    --fail: #f08a80;
    --fail-bg: #2a1e1d;
    --pass-bg: #1a2622;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  padding: 2rem 1.25rem 4rem;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

main { max-width: 44rem; margin: 0 auto; }

h1 { font-size: 1.9rem; margin: 0 0 .5rem; letter-spacing: -.02em; }
h2 { font-size: 1.15rem; margin: 0 0 .75rem; letter-spacing: -.01em; }

.lead { font-size: 1.05rem; color: var(--muted); margin: 0 0 2.5rem; max-width: 34rem; }

section { margin-bottom: 2.5rem; }

label { display: block; font-weight: 600; margin-bottom: .25rem; }
.hint { margin: 0 0 .75rem; color: var(--muted); font-size: .9rem; }

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: .875em;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 4px;
  padding: .1em .35em;
}

textarea {
  width: 100%;
  padding: .85rem;
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--line);
  border-radius: 8px;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: .85rem;
  line-height: 1.5;
  resize: vertical;
}
textarea:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

.actions { display: flex; gap: .6rem; flex-wrap: wrap; margin-top: .85rem; }

button {
  font: inherit;
  font-weight: 600;
  padding: .6rem 1.1rem;
  border-radius: 8px;
  border: 1px solid var(--accent);
  background: var(--accent);
  color: var(--bg);
  cursor: pointer;
}
button:hover { opacity: .9; }
button.secondary { background: transparent; color: var(--accent); }
button:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.verdict {
  padding: 1rem 1.15rem;
  border-radius: 8px;
  border: 1px solid var(--line);
  margin-bottom: 1.25rem;
}
.verdict.pass { background: var(--pass-bg); border-color: var(--pass); }
.verdict.fail { background: var(--fail-bg); border-color: var(--fail); }
.verdict h2 { margin: 0 0 .35rem; }
.verdict.pass h2 { color: var(--pass); }
.verdict.fail h2 { color: var(--fail); }
.verdict p { margin: 0; color: var(--muted); }

ul.checks { list-style: none; padding: 0; margin: 0 0 1.5rem; }
ul.checks li {
  display: grid;
  grid-template-columns: 3.4rem 1fr;
  gap: .5rem;
  padding: .8rem 0;
  border-top: 1px solid var(--line);
}
ul.checks li:last-child { border-bottom: 1px solid var(--line); }
.badge { font-size: .72rem; font-weight: 700; letter-spacing: .06em; padding-top: .2rem; }
.badge.pass { color: var(--pass); }
.badge.fail { color: var(--fail); }
.check-label { font-weight: 600; }
.check-detail { color: var(--muted); font-size: .9rem; }

dl.summary {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: .4rem 1.25rem;
  margin: 0;
  font-size: .92rem;
}
dl.summary dt { color: var(--muted); }
dl.summary dd { margin: 0; }
dl.summary dd.mono {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: .8rem;
  overflow-wrap: anywhere;
}

.explainer { border-top: 1px solid var(--line); padding-top: 1.75rem; }
.explainer p { color: var(--muted); }
.aside { font-size: .9rem; }
a { color: var(--accent); }

.error {
  padding: 1rem 1.15rem;
  border: 1px solid var(--fail);
  background: var(--fail-bg);
  border-radius: 8px;
  color: var(--fail);
}

@media (max-width: 30rem) {
  ul.checks li { grid-template-columns: 1fr; gap: .15rem; }
  dl.summary { grid-template-columns: 1fr; }
  dl.summary dt { margin-top: .5rem; }
}