:root {
  --bg: #f5f7f6;
  --surface: #ffffff;
  --ink: #12231f;
  --muted: #4f5d59;
  --line: rgba(18, 35, 31, 0.14);
  --accent: #1d7a5c;
  --focus: #0b57d0;
  --note-bg: #fff6e0;
  --note-line: #c78a2c;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--bg);
  font-family: "Avenir Next", "Segoe UI", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  font-size: 1.0625rem;
  line-height: 1.6;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  padding: 0.5rem 1rem;
  background: var(--surface);
}

.skip-link:focus { left: 1rem; }

header, main, footer {
  max-width: 46rem;
  margin: 0 auto;
  padding: 0 1rem;
}

header { padding-top: 1.5rem; }

header a.home { color: var(--ink); font-weight: 600; text-decoration: none; }

main {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  margin-top: 1rem;
  padding: 1.5rem clamp(1rem, 4vw, 2.5rem) 2rem;
}

h1 { font-size: 1.9rem; line-height: 1.25; margin: 0.5rem 0 0.25rem; }
h2 { font-size: 1.35rem; margin: 2rem 0 0.5rem; }
h3 { font-size: 1.1rem; margin: 1.5rem 0 0.25rem; }

.meta { color: var(--muted); margin: 0 0 1rem; }

.summary {
  background: var(--bg);
  border-left: 4px solid var(--accent);
  padding: 0.75rem 1rem;
  margin: 1rem 0;
}

.draft {
  background: var(--note-bg);
  border: 1px solid var(--note-line);
  border-radius: 8px;
  padding: 0.75rem 1rem;
  margin: 1rem 0;
}

mark.todo { background: #ffe58a; padding: 0 0.2em; }

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

a:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}

table { border-collapse: collapse; width: 100%; margin: 0.75rem 0; font-size: 0.95rem; }
th, td { border: 1px solid var(--line); padding: 0.5rem; text-align: left; vertical-align: top; }
th { background: var(--bg); }

.table-scroll { overflow-x: auto; }

nav.toc ol { padding-left: 1.25rem; }

footer { color: var(--muted); padding: 1.5rem 1rem 3rem; font-size: 0.95rem; }
footer a { margin-right: 1rem; }

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1a17;
    --surface: #16241f;
    --ink: #e7efec;
    --muted: #a9b8b3;
    --line: rgba(231, 239, 236, 0.16);
    --accent: #5fd3a8;
    --note-bg: #3a2f14;
  }
  mark.todo { color: #12231f; }
}