:root {
  color-scheme: light dark;
  --bg: #f8fafc;
  --card: #ffffff;
  --text: #0f172a;
  --muted: #475569;
  --line: #e2e8f0;
  --link: #1d4ed8;
  --accent: #eff6ff;
  --mark: #fef3c7;
  --mark-text: #92400e;
  --note: #fffbeb;
  --note-line: #fcd34d;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1220;
    --card: #111827;
    --text: #e8eef5;
    --muted: #94a3b8;
    --line: #1f2937;
    --link: #93c5fd;
    --accent: #172033;
    --mark: #451a03;
    --mark-text: #fde68a;
    --note: #1c1508;
    --note-line: #92400e;
  }
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  background: var(--bg);
}

body {
  margin: 0;
  max-width: 100%;
  overflow-x: clip;
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  font-size: 1rem;
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
  overflow-wrap: break-word;
}

a { color: var(--link); }

a:hover { text-decoration: none; }

.skip {
  position: absolute;
  left: 1rem;
  top: -4rem;
  background: var(--card);
  color: var(--text);
  padding: 0.5rem 0.75rem;
  border-radius: 0.5rem;
}

.skip:focus { top: 0.75rem; }

header, footer {
  max-width: 46rem;
  margin: 0 auto;
  padding: 1rem 1rem 0;
  padding-left: max(1rem, env(safe-area-inset-left));
  padding-right: max(1rem, env(safe-area-inset-right));
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem 1rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: inherit;
  text-decoration: none;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.brand img {
  width: 2rem;
  height: 2rem;
  border-radius: 999px;
}

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem 1rem;
  font-size: 0.9375rem;
}

main {
  max-width: 46rem;
  margin: 0 auto;
  padding: 1rem;
  padding-left: max(1rem, env(safe-area-inset-left));
  padding-right: max(1rem, env(safe-area-inset-right));
}

article {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 1.25rem;
  padding: 1.15rem 1rem 1.5rem;
  overflow-wrap: break-word;
}

h1 {
  font-size: clamp(1.5rem, 6.5vw, 2rem);
  line-height: 1.2;
  letter-spacing: -0.03em;
  margin: 0 0 0.5rem;
}

h2 {
  font-size: clamp(1.125rem, 4.4vw, 1.25rem);
  line-height: 1.3;
  margin: 1.75rem 0 0.6rem;
}

h3 {
  font-size: 1.05rem;
  margin: 1.25rem 0 0.4rem;
}

p, li, td { font-size: 1rem; line-height: 1.55; }

code, a { overflow-wrap: anywhere; }

.meta, .muted { color: var(--muted); }

.note {
  background: var(--note);
  border: 1px solid var(--note-line);
  border-radius: 0.9rem;
  padding: 0.85rem 1rem;
  margin: 1rem 0 1.25rem;
}

mark, .ph {
  background: var(--mark);
  color: var(--mark-text);
  padding: 0 0.2em;
  border-radius: 0.25em;
  font-weight: 650;
}

ul, ol { padding-left: 1.2rem; }

li + li { margin-top: 0.35rem; }

table {
  width: 100%;
  border-collapse: collapse;
  margin: 0.75rem 0 1rem;
}

th, td {
  text-align: left;
  vertical-align: top;
  border-top: 1px solid var(--line);
  padding: 0.55rem 0.4rem;
}

th {
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
}

@media (max-width: 640px) {
  table,
  thead,
  tbody,
  tr,
  th,
  td {
    display: block;
    width: 100%;
  }

  thead {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
  }

  tr {
    border: 1px solid var(--line);
    border-radius: 0.85rem;
    margin: 0 0 0.75rem;
    padding: 0.75rem 0.85rem;
  }

  td {
    border: 0;
    padding: 0.15rem 0;
  }

  td:first-child {
    font-weight: 700;
    padding-bottom: 0.3rem;
  }
}

footer {
  padding-bottom: 2.5rem;
  color: var(--muted);
  font-size: 0.9rem;
}