:root {
  --text: #111;
  --muted: #555;
  --link: #0645ad;
  --rule: #ddd;
  --code-bg: #f4f4f4;
}
* { box-sizing: border-box; }
html { background: #fff; }
body {
  margin: 0;
  background: #fff;
  color: var(--text);
  font: 16px/1.6 Verdana, Geneva, "DejaVu Sans", sans-serif;
}
header, main, footer {
  max-width: 820px;
  margin: 0 auto;
  padding: 0 16px;
}
header {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 20px;
  padding-top: 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--rule);
}
.brand {
  font-size: 22px;
  font-weight: bold;
  letter-spacing: 1px;
  color: var(--text);
  text-decoration: none;
}
nav { display: flex; flex-wrap: wrap; gap: 4px 16px; font-size: 14px; }
nav a { color: var(--link); text-decoration: none; }
nav a:hover { text-decoration: underline; }
main { padding-top: 24px; padding-bottom: 40px; }
h1 { font-size: 30px; line-height: 1.25; margin: 0 0 16px; }
h2 { font-size: 22px; margin: 40px 0 12px; }
h3 { font-size: 18px; margin: 28px 0 8px; }
p { margin: 0 0 14px; }
a { color: var(--link); }
code, pre {
  font-family: Consolas, "DejaVu Sans Mono", Menlo, monospace;
  font-size: 14px;
}
code { background: var(--code-bg); padding: 1px 4px; border-radius: 3px; }
pre {
  background: var(--code-bg);
  padding: 12px 14px;
  overflow-x: auto;
  border-radius: 4px;
  margin: 0 0 16px;
  line-height: 1.45;
}
pre code { background: none; padding: 0; }
table {
  border-collapse: collapse;
  width: 100%;
  margin: 0 0 18px;
  font-size: 15px;
  display: block;
  overflow-x: auto;
}
th, td { border: 1px solid var(--rule); padding: 6px 10px; text-align: left; vertical-align: top; }
th { background: #fafafa; }
ol, ul { margin: 0 0 14px; padding-left: 26px; }
li { margin-bottom: 4px; }
blockquote { margin: 0 0 14px; padding-left: 14px; border-left: 3px solid var(--rule); color: var(--muted); }
figure { margin: 18px 0 22px; }
figure svg { display: block; max-width: 100%; height: auto; }
figcaption { font-size: 13px; color: var(--muted); margin-top: 6px; }
.lead { font-size: 18px; }
.two { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
@media (max-width: 640px) { .two { grid-template-columns: 1fr; } }
footer { border-top: 1px solid var(--rule); padding-top: 14px; padding-bottom: 30px; font-size: 13px; color: var(--muted); }