/* Paper Sudoku support site — the app's exercise-book look. */
:root {
  --paper: #FBFAF6;
  --grid: #DCE5EE;
  --margin: #E59A97;
  --ink: #2F3237;
  --muted: #474B53;
  --card: #FFFFFF;
  --sticky: #FFF0A6;
  --highlighter: rgba(255, 228, 92, 0.85);
  --red: #C8372D;
  --tape: rgba(169, 199, 224, 0.75);
}
@media (prefers-color-scheme: dark) {
  :root {
    --paper: #1B1E23;
    --grid: rgba(140, 170, 205, 0.11);
    --margin: rgba(229, 154, 151, 0.38);
    --ink: #E8E5DC;
    --muted: #B4BAC4;
    --card: #2A2E35;
    --sticky: #D9CA78;
    --highlighter: rgba(255, 228, 92, 0.3);
    --red: #FF7A6B;
    --tape: rgba(140, 170, 200, 0.55);
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  color: var(--ink);
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 20px 20px;
  font-family: 'Atkinson Hyperlegible', -apple-system, system-ui, sans-serif;
  font-size: 17px;
  line-height: 1.6;
}
.page {
  position: relative;
  max-width: 680px;
  margin: 0 auto;
  padding: 56px 24px 96px 64px;
}
.page::before {
  /* The red margin rule down the left of the page. */
  content: "";
  position: absolute;
  top: 0; bottom: 0; left: 40px;
  width: 1.5px;
  background: var(--margin);
}
.hand { font-family: 'Patrick Hand', 'Comic Sans MS', cursive; font-weight: 400; }
.typed { font-family: 'Courier Prime', ui-monospace, monospace; }
header { display: flex; align-items: center; gap: 20px; margin-bottom: 36px; }
header img { width: 84px; height: 84px; border-radius: 19px; box-shadow: 0 6px 18px rgba(0,0,0,0.15); }
.wordmark { line-height: 1; }
.wordmark .paper { display: block; font-size: 26px; color: var(--muted); }
.wordmark .sudoku { font-size: 56px; position: relative; z-index: 0; }
.mark {
  /* A highlighter swipe behind a word. */
  background: linear-gradient(transparent 52%, var(--highlighter) 52%, var(--highlighter) 92%, transparent 92%);
  padding: 0 4px;
}
h1, h2, h3 { font-family: 'Patrick Hand', 'Comic Sans MS', cursive; font-weight: 400; line-height: 1.2; }
h1 { font-size: 44px; margin: 0 0 6px; }
h2 { font-size: 30px; margin: 44px 0 12px; }
h3 { font-size: 24px; margin: 0 0 6px; }
p { margin: 0 0 14px; }
ul { margin: 0 0 14px; padding-left: 22px; }
li { margin-bottom: 8px; }
a { color: var(--ink); text-decoration-thickness: 1.5px; text-underline-offset: 3px; }
a:hover { color: var(--red); }
.lead { font-size: 19px; }
.sticky {
  position: relative;
  background: var(--sticky);
  color: #2F3237;
  padding: 26px 24px 20px;
  margin: 32px 4px 8px 0;
  box-shadow: 0 10px 18px -8px rgba(60, 50, 10, 0.35);
  transform: rotate(-0.8deg);
}
.sticky::before {
  content: "";
  position: absolute;
  top: -11px; left: 42%;
  width: 92px; height: 22px;
  background: var(--tape);
  transform: rotate(3deg);
}
.sticky a { color: #2F3237; }
.card {
  background: var(--card);
  border-radius: 6px;
  border: 1px solid rgba(47, 50, 55, 0.12);
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.08);
  padding: 18px 22px;
  margin-bottom: 14px;
}
.card p:last-child, .card ul:last-child { margin-bottom: 0; }
.button {
  display: inline-block;
  font-family: 'Patrick Hand', 'Comic Sans MS', cursive;
  font-size: 24px;
  color: var(--ink);
  text-decoration: none;
  padding: 6px 22px;
  border: 2px solid var(--ink);
  border-radius: 255px 15px 225px 15px / 15px 225px 15px 255px;
  background: var(--highlighter);
}
.button:hover { color: var(--ink); transform: rotate(-1deg); }
.red { color: var(--red); }
.updated { color: var(--muted); font-size: 15px; }
footer {
  margin-top: 56px;
  padding-top: 18px;
  border-top: 1.5px solid rgba(127, 127, 127, 0.25);
  color: var(--muted);
  font-size: 15px;
  display: flex; gap: 20px; flex-wrap: wrap;
}
footer a { color: var(--muted); }
@media (max-width: 480px) {
  .page { padding: 40px 18px 72px 46px; }
  .page::before { left: 30px; }
  .wordmark .sudoku { font-size: 46px; }
  header img { width: 68px; height: 68px; border-radius: 15px; }
  h1 { font-size: 38px; }
}