:root {
  --paper: #FBF7EC;
  --grid: #CFDFF1;
  --margin: #E58A80;
  --ink: #1F2A44;
  --label: #5F6A80;
  --pen: #2446A6;
  --surface: #FFFDF8;
  --edge: #E6DDC6;
}
@media (prefers-color-scheme: dark) {
  :root {
    --paper: #1E2230;
    --grid: rgba(150, 170, 210, 0.10);
    --margin: rgba(229, 138, 128, 0.55);
    --ink: #F1EBDD;
    --label: #A9B2C6;
    --pen: #8FB0FF;
    --surface: #2A3042;
    --edge: #3A4259;
  }
}
* { 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: 28px 28px;
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}
main {
  max-width: 680px;
  margin: 0 auto;
  padding: 40px 16px 64px;
}
.sheet {
  background: var(--surface);
  border: 1px solid var(--edge);
  border-left: 3px solid var(--margin);
  border-radius: 14px;
  padding: 28px 24px;
}
header { display: flex; align-items: center; gap: 14px; margin-bottom: 8px; }
.mark {
  font: 800 30px/1 -apple-system, sans-serif;
  color: var(--pen);
  letter-spacing: -1px;
}
h1 { font-size: 26px; line-height: 1.25; margin: 0; }
h2 { font-size: 19px; margin: 28px 0 6px; }
p, li { margin: 6px 0; }
ul { padding-left: 22px; }
.meta { color: var(--label); font-size: 15px; margin: 0 0 20px; }
.lang { display: flex; gap: 8px; margin: 18px 0 4px; }
.lang a {
  color: var(--pen);
  border: 1px solid var(--edge);
  border-radius: 999px;
  padding: 4px 12px;
  text-decoration: none;
  font-size: 15px;
}
a { color: var(--pen); }
hr { border: 0; border-top: 1px dashed var(--edge); margin: 36px 0; }
footer { color: var(--label); font-size: 14px; margin-top: 28px; text-align: center; }