/* Coda's ground and ink (DESIGN.md §3): the canvas is never pure black, hierarchy is ink, and
   nothing has a shadow or a border. Light on a light phone, dark on a dark one. */
:root {
  --canvas: #f3f4f6; --ink: #1a1b1e; --subtle: #5c616a; --hairline: #dee1e6; --code: #e8eaee;
  --accent: #4a56c4;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root { --canvas: #010102; --ink: #f7f8f8; --subtle: #8a8f98; --hairline: #18191a; --code: #141516;
          --accent: #828fff; }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--canvas); color: var(--ink);
  font: 17px/1.47 -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Helvetica Neue", sans-serif;
  letter-spacing: -0.01em;
}
main { max-width: 680px; margin: 0 auto; padding: 48px 22px 80px; }
h1 { font-size: 34px; line-height: 1.15; letter-spacing: -0.03em; margin: 8px 0 6px; font-weight: 700; }
h2 {
  font-size: 15px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.04em;
  color: var(--subtle); margin: 40px 0 10px;
}
p, li { margin: 0 0 12px; }
ul { padding-left: 20px; margin: 0 0 12px; }
.meta { color: var(--subtle); font-size: 14px; margin-bottom: 28px; }
.lede { font-size: 19px; padding-bottom: 28px; border-bottom: 1px solid var(--hairline); }
code {
  font: 14px/1.4 ui-monospace, "SF Mono", Menlo, monospace; background: var(--code);
  padding: 1px 6px; border-radius: 6px;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.lang { display: flex; gap: 18px; font-size: 15px; }
.lang a { color: var(--subtle); }
body[data-lang="en"] .lang a[data-lang="en"],
body[data-lang="zh"] .lang a[data-lang="zh"] { color: var(--ink); font-weight: 600; }
body[data-lang="en"] article[lang="zh-Hans"],
body[data-lang="zh"] article[lang="en"] { display: none; }
article + article { margin-top: 64px; }
body[data-lang] article + article { margin-top: 0; }