:root {
  --bg: #f4f5f7; --surface: #ffffff; --side: #17202e; --side-text: #c5cedb; --side-on: #25324a;
  --text: #1a2331; --muted: #5b6676; --line: #dfe3e9; --accent: #0a5fb4; --accent-text: #ffffff;
  --note-bg: #fff6dc; --note: #6b4e00; --tip-bg: #e3f0fd; --tip: #0b3f73; --warn-bg: #fde6e4; --warn: #8f2219;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #10141a; --surface: #1a2029; --side: #0c1016; --side-text: #aab4c3; --side-on: #1d2735;
    --text: #e5e9ef; --muted: #98a3b3; --line: #2c3542; --accent: #72b4f5; --accent-text: #0b1420;
    --note-bg: #3a3112; --note: #f0d68a; --tip-bg: #12283f; --tip: #b5d8fb; --warn-bg: #44201c; --warn: #f6a79f;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font: 16px/1.65 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  display: grid; grid-template-columns: 248px minmax(0, 1fr); min-height: 100vh;
}
a { color: var(--accent); text-underline-offset: 2px; }
.skip { position: absolute; left: -999px; }
.skip:focus { left: 1rem; top: 1rem; background: var(--surface); padding: .5rem 1rem; z-index: 2; }

.side { background: var(--side); color: var(--side-text); padding: 1.2rem .85rem; position: sticky; top: 0; height: 100vh; display: flex; flex-direction: column; gap: 1.3rem; overflow-y: auto; }
.brand { display: flex; align-items: center; gap: .6rem; padding: 0 .45rem; color: #fff; font-weight: 700; letter-spacing: .08em; text-decoration: none; }
.brand small { font-weight: 400; letter-spacing: 0; opacity: .7; }
.mark { display: grid; place-items: center; width: 28px; height: 28px; border-radius: 7px; background: var(--accent); color: var(--accent-text); letter-spacing: 0; }
.side nav { display: grid; gap: 2px; }
.side nav a { padding: .42rem .7rem; border-radius: 7px; color: var(--side-text); text-decoration: none; }
.side nav a:hover { background: var(--side-on); color: #fff; }
.side nav a.on { background: var(--side-on); color: #fff; font-weight: 600; box-shadow: inset 3px 0 0 var(--accent); }
.applink { margin-top: auto; padding: .5rem .7rem; color: #fff; }

main { padding: 2.2rem 2.5rem 4rem; max-width: 860px; width: 100%; }
h1 { font-size: 2rem; line-height: 1.2; margin: 0 0 .4rem; letter-spacing: -.015em; }
h2 { font-size: 1.3rem; margin: 2.4rem 0 .6rem; padding-top: .4rem; border-top: 1px solid var(--line); }
h3 { font-size: 1.05rem; margin: 1.6rem 0 .4rem; }
.lead { font-size: 1.1rem; color: var(--muted); margin: 0 0 1.5rem; }
p, ul, ol { margin: 0 0 1rem; }
li { margin: .3rem 0; }
code { font: .88em/1.4 ui-monospace, "Cascadia Mono", Consolas, monospace; background: var(--surface); border: 1px solid var(--line); border-radius: 5px; padding: .08em .35em; overflow-wrap: anywhere; }
pre { background: var(--surface); border: 1px solid var(--line); border-radius: 8px; padding: .8rem 1rem; overflow-x: auto; margin: 0 0 1rem; }
pre code { border: 0; padding: 0; background: none; font-size: .88rem; overflow-wrap: normal; }
kbd { font: inherit; font-size: .88em; background: var(--surface); border: 1px solid var(--line); border-bottom-width: 2px; border-radius: 5px; padding: .05em .4em; }

table { width: 100%; border-collapse: collapse; background: var(--surface); border: 1px solid var(--line); border-radius: 8px; margin: 0 0 1.2rem; font-size: .95rem; }
.tablewrap { overflow-x: auto; }
th, td { text-align: left; padding: .5rem .8rem; border-bottom: 1px solid var(--line); vertical-align: top; }
th { font-size: .78rem; text-transform: uppercase; letter-spacing: .05em; color: var(--muted); }
tr:last-child td { border-bottom: 0; }

.note, .tip, .warn { border-radius: 8px; padding: .7rem 1rem; margin: 0 0 1.2rem; }
.note { background: var(--note-bg); color: var(--note); }
.tip { background: var(--tip-bg); color: var(--tip); }
.warn { background: var(--warn-bg); color: var(--warn); }
.note a, .tip a, .warn a { color: inherit; }
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: .9rem; margin: 0 0 1.5rem; padding: 0; list-style: none; }
.cards a { display: block; height: 100%; background: var(--surface); border: 1px solid var(--line); border-radius: 10px; padding: .9rem 1.1rem; text-decoration: none; color: var(--text); }
.cards a:hover { border-color: var(--accent); }
.cards b { display: block; color: var(--accent); margin-bottom: .2rem; }
.cards span { color: var(--muted); font-size: .93rem; }
.steps { counter-reset: step; list-style: none; padding: 0; }
.steps > li { counter-increment: step; position: relative; padding-left: 2.6rem; margin: .8rem 0; }
.steps > li::before { content: counter(step); position: absolute; left: 0; top: .05rem; width: 1.8rem; height: 1.8rem; border-radius: 50%; background: var(--accent); color: var(--accent-text); display: grid; place-items: center; font-weight: 700; font-size: .9rem; }
.pager { display: flex; justify-content: space-between; gap: 1rem; margin-top: 3rem; padding-top: 1.2rem; border-top: 1px solid var(--line); }
.pager .next { margin-left: auto; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

@media (max-width: 860px) {
  body { display: block; }
  .side { position: static; height: auto; }
  .side nav { display: flex; flex-wrap: wrap; }
  .side nav a.on { box-shadow: none; }
  .applink { margin-top: 0; }
  main { padding: 1.3rem 1rem 3rem; }
  h1 { font-size: 1.6rem; }
}