:root {
  --paper: #f2efe6;
  --black: #111111;
  --red: #DA291C;
  --line: rgba(17, 17, 17, .28);
  --sans: Inter, "Helvetica Neue", Helvetica, Arial, "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--black);
  font-family: var(--sans);
  font-size: 16px;
  font-weight: 400;
  line-height: 1.45;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
a:focus-visible { outline: 2px solid var(--red); outline-offset: 4px; }
::selection { background: var(--red); color: var(--paper); }

.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--black);
  color: var(--paper);
  border-bottom: 1px solid var(--black);
}

.topbar-in,
.layout {
  width: min(1440px, calc(100% - 64px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  column-gap: 24px;
}

.topbar-in {
  min-height: 72px;
  align-items: center;
}

.brand {
  grid-column: 1 / span 3;
  display: flex;
  align-items: baseline;
  gap: 12px;
  font-weight: 700;
}

.brand .mark {
  width: 14px;
  height: 14px;
  background: var(--red);
  box-shadow: none;
  border-radius: 0;
  transform: none;
}

.brand b { color: var(--paper); font-size: 16px; }
.brand span:not(.mark) { color: var(--paper); font-size: 11px; letter-spacing: .08em; text-transform: uppercase; opacity: .64; }
.topbar .spacer { display: none; }
.topbar .tag,
.topbar .gh,
.topbar .home { font-size: 11px; letter-spacing: .08em; text-transform: uppercase; font-weight: 700; }
.topbar .tag { grid-column: 6 / span 3; color: var(--paper); border: 0; border-radius: 0; padding: 0; opacity: .64; }
.topbar .home { grid-column: 9 / span 1; color: var(--paper); border: 0; }
.topbar .gh { grid-column: 10 / -1; color: var(--paper); border: 0; }
.topbar .home:hover,
.topbar .gh:hover { color: var(--red); }

.layout {
  padding-bottom: 112px;
}

.side {
  grid-column: 1 / span 2;
  position: sticky;
  top: 104px;
  align-self: start;
  padding-top: 64px;
}

.side h4,
.side .meta,
.eyebrow,
.sec-kicker,
.sec-num,
h4.mini,
.card .tag,
.feat .num,
.step .no,
.light .name,
.term .foot,
.term-bar .t,
.spec th,
footer .sm,
.foot-rule {
  font-family: var(--sans);
  letter-spacing: .1em;
  text-transform: uppercase;
}

.side h4 { margin: 0 0 18px; color: var(--red); font-size: 11px; font-weight: 700; }
.side ul { margin: 0; padding: 0; list-style: none; border-left: 1px solid var(--line); }
.side li a { display: block; margin-left: -1px; padding: 7px 0 7px 14px; border-left: 2px solid transparent; border-bottom: 0; color: rgba(17, 17, 17, .64); font-size: 12px; line-height: 1.35; }
.side li a:hover { color: var(--black); }
.side li a.active { padding-left: 18px; color: var(--red); border-left-color: var(--red); font-weight: 700; }
.side li a .n { margin-right: 8px; color: inherit; font-size: 10px; font-weight: 700; }
.side .meta { margin-top: 28px; padding-top: 18px; border-top: 1px solid var(--black); color: rgba(17, 17, 17, .54); font-size: 10px; line-height: 2; }

main { grid-column: 4 / -1; min-width: 0; }

.hero {
  margin: 0 -24px;
  padding: 80px 24px 44px;
  background: var(--paper);
  color: var(--black);
  border-bottom: 1px solid var(--black);
  overflow: visible;
}

.hero::before,
.hero::after { display: none; }
.hero > * { position: static; z-index: auto; }
.eyebrow { display: flex; gap: 12px; align-items: center; color: var(--red); font-size: 11px; font-weight: 700; }
.eyebrow .pip { width: 10px; height: 10px; border-radius: 0; background: var(--red); box-shadow: none; }
.hero h1 { max-width: none; margin: 30px 0 0; color: var(--black); font-size: 120px; line-height: .88; letter-spacing: 0; font-weight: 700; }
.hero h1 em { color: var(--red); font-family: var(--sans); font-size: .42em; letter-spacing: 0; font-weight: 700; white-space: nowrap; }
.hero .lede { max-width: 39rem; margin: 40px 0 0; color: var(--black); font-size: 18px; line-height: 1.45; }
.hero .lede strong { color: var(--red); font-weight: 700; }
.chips { display: flex; flex-wrap: wrap; gap: 8px 12px; margin-top: 34px; }
.chip { padding: 6px 10px; border: 1px solid var(--black); border-radius: 0; background: transparent; color: var(--black); font-family: var(--sans); font-size: 11px; line-height: 1.2; letter-spacing: .04em; }
.chip.hl { background: var(--red); border-color: var(--red); color: var(--paper); font-weight: 700; }
.hero-actions { margin-top: 40px; display: flex; flex-wrap: wrap; gap: 12px; }
.btn { display: inline-flex; align-items: center; gap: 10px; padding: 13px 18px; border: 1px solid var(--black); border-radius: 0; font-family: var(--sans); font-size: 11px; line-height: 1.2; letter-spacing: .08em; text-transform: uppercase; font-weight: 700; }
.btn-primary { background: var(--red); border-color: var(--red); color: var(--paper); }
.btn-primary:hover { background: var(--black); border-color: var(--black); }
.btn-ghost { color: var(--black); border-color: var(--black); }
.btn-ghost:hover { background: var(--black); color: var(--paper); }
.hero-foot { margin-top: 52px; padding-top: 14px; border-top: 1px solid var(--black); display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; color: rgba(17, 17, 17, .62); font-family: var(--sans); font-size: 10px; line-height: 1.2; letter-spacing: .1em; text-transform: uppercase; font-weight: 700; }

section { padding-top: 112px; scroll-margin-top: 88px; }
.sec-head { margin-bottom: 56px; padding-top: 16px; border-top: 2px solid var(--black); }
.sec-top { display: flex; gap: 14px; align-items: baseline; }
.sec-num { color: var(--red); font-size: 11px; font-weight: 700; }
.sec-kicker { color: rgba(17, 17, 17, .56); font-size: 10px; font-weight: 700; }
.sec-head h2 { max-width: 8ch; margin: 18px 0 0; color: var(--black); font-family: var(--sans); font-size: 84px; line-height: .9; letter-spacing: 0; font-weight: 700; }
.sec-head .lede { max-width: 37rem; margin: 24px 0 0; color: rgba(17, 17, 17, .72); font-size: 17px; line-height: 1.45; }
h3.sub { margin: 72px 0 22px; display: flex; gap: 14px; align-items: baseline; color: var(--black); font-family: var(--sans); font-size: 22px; line-height: 1.1; font-weight: 700; }
h3.sub .idx { color: var(--red); font-family: var(--sans); font-size: 11px; letter-spacing: .1em; font-weight: 700; }
h4.mini { margin: 42px 0 14px; color: var(--red); font-size: 10px; line-height: 1.2; font-weight: 700; }
p { margin: 0 0 18px; }
.muted { color: rgba(17, 17, 17, .64); }

.note { margin: 28px 0; padding: 18px 20px; border: 1px solid var(--black); border-left: 1px solid var(--black); border-radius: 0; background: transparent; font-size: 15px; }
.note .lbl { display: block; margin-bottom: 8px; color: var(--red); font-size: 10px; line-height: 1.2; letter-spacing: .1em; text-transform: uppercase; font-weight: 700; }
.note.calm { border-left: 1px solid var(--black); background: transparent; }
.note.calm .lbl { color: var(--black); }

.grid-2,
.grid-3 { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: 0 24px; margin: 28px 0; }
.grid-2 > * { grid-column: span 3; }
.grid-3 > * { grid-column: span 2; }
.card { min-height: 196px; padding: 18px 0 0; border: 0; border-top: 1px solid var(--black); border-radius: 0; background: transparent; box-shadow: none; }
.card:hover { transform: none; border-color: var(--black); box-shadow: none; }
.card .tag { color: var(--red); font-size: 10px; font-weight: 700; }
.card h4 { margin: 22px 0 12px; color: var(--black); font-family: var(--sans); font-size: 18px; line-height: 1.1; font-weight: 700; }
.card p { color: rgba(17, 17, 17, .72); font-size: 14px; line-height: 1.5; }
.card .kv { margin-top: 16px; padding-top: 12px; border-top: 1px solid var(--line); color: rgba(17, 17, 17, .72); font-family: var(--sans); font-size: 12px; line-height: 1.8; white-space: pre-wrap; }
.card .kv b { color: var(--black); font-weight: 700; }

.term { margin: 34px 0 0; overflow: hidden; border: 1px solid var(--black); border-radius: 0; background: var(--black); box-shadow: none; }
.term-bar { display: flex; align-items: center; gap: 8px; padding: 11px 16px; border-bottom: 1px solid rgba(242, 239, 230, .35); background: var(--black); }
.term-bar .d { width: 8px; height: 8px; border-radius: 0; background: var(--paper); }
.term-bar .d:first-child { background: var(--red); }
.term-bar .t { margin-left: 8px; color: var(--paper); font-size: 10px; font-weight: 700; opacity: .64; }
.term pre { margin: 0; padding: 24px 20px; overflow-x: auto; color: var(--paper); font-family: var(--sans); font-size: 12px; line-height: 1.6; letter-spacing: 0; }
.term pre .k { color: var(--red); }
.term pre .c { color: rgba(242, 239, 230, .52); }
.term .foot { display: flex; flex-wrap: wrap; gap: 18px; padding: 12px 16px; border-top: 1px solid rgba(242, 239, 230, .35); color: rgba(242, 239, 230, .64); font-size: 10px; font-weight: 700; }

code.inline { padding: 2px 5px; border: 1px solid var(--black); border-radius: 0; background: transparent; color: var(--red); font-family: var(--sans); font-size: .86em; white-space: normal; overflow-wrap: anywhere; }
.card .kv { overflow-wrap: anywhere; }

.feat { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 24px; margin: 28px 0; padding: 0; list-style: none; }
.feat li { min-height: 150px; padding: 16px 0 22px; border-top: 1px solid var(--black); display: flex; gap: 18px; }
.feat li:nth-child(2n) { padding-left: 0; }
.feat .num { flex: none; padding-top: 3px; color: var(--red); font-size: 10px; font-weight: 700; }
.feat h4 { margin: 0 0 10px; color: var(--black); font-family: var(--sans); font-size: 17px; line-height: 1.1; font-weight: 700; }
.feat p { color: rgba(17, 17, 17, .72); font-size: 14px; line-height: 1.5; }

.step { margin-left: 0; padding: 24px 0 42px; border-left: 0; border-top: 1px solid var(--black); }
.step:last-child { padding-bottom: 0; border-left: 0; }
.step .dot { display: none; }
.step .body { padding-left: 0; }
.step .no { color: var(--red); font-size: 10px; font-weight: 700; }
.step h3 { margin: 16px 0 14px; color: var(--black); font-family: var(--sans); font-size: 26px; line-height: 1.1; font-weight: 700; }
.step ol,
.step ul { margin: 0 0 18px; padding-left: 22px; }
.step li { margin-bottom: 9px; }
.step li::marker { color: var(--red); font-family: var(--sans); font-weight: 700; }

.flow { margin: 30px 0; }
.flow .item { display: grid; grid-template-columns: 42px minmax(0, 1fr); gap: 18px; align-items: start; margin: 0; padding: 18px 0; border: 0; border-top: 1px solid var(--black); border-radius: 0; background: transparent; }
.flow .item .n { display: flex; width: 32px; height: 32px; align-items: center; justify-content: center; border: 0; border-radius: 0; background: var(--red); color: var(--paper); font-family: var(--sans); font-size: 12px; font-weight: 700; }
.flow .item.hl { border-color: var(--black); background: transparent; }
.flow .item.hl .n { border: 0; background: var(--black); color: var(--paper); }
.flow .item .txt { font-size: 15px; line-height: 1.5; }
.flow .item .txt b { color: var(--black); font-weight: 700; }
.flow .arrow { margin: -4px 0 0 14px; color: var(--red); font-family: var(--sans); font-size: 14px; letter-spacing: 0; }

.lights { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px; margin: 24px 0; }
.light { padding: 16px 0; border-top: 1px solid var(--black); border-radius: 0; background: transparent; }
.light .name { margin-bottom: 14px; color: var(--red); font-size: 10px; font-weight: 700; }
.light .row { display: flex; align-items: center; gap: 10px; margin-bottom: 8px; color: rgba(17, 17, 17, .72); font-size: 13px; line-height: 1.45; }
.bulb { width: 10px; height: 10px; flex: none; border-radius: 0; }
.bulb.r { background: var(--red); box-shadow: none; }
.bulb.l { background: var(--black); }
.bulb.n { border: 1px solid var(--black); background: transparent; }
.light code { padding: 0; border: 0; border-radius: 0; background: transparent; color: var(--black); font-family: var(--sans); font-size: 11px; }

details { padding: 0; border-top: 1px solid var(--black); }
details:last-of-type { border-bottom: 1px solid var(--black); }
summary { position: relative; padding: 22px 48px 22px 0; color: var(--black); font-family: var(--sans); font-size: 18px; line-height: 1.35; font-weight: 700; cursor: pointer; }
summary::-webkit-details-marker { display: none; }
summary:hover { color: var(--red); }
summary .q { margin-right: 14px; color: var(--red); font-size: 10px; letter-spacing: .1em; font-weight: 700; }
summary::after { content: "+"; position: absolute; right: 4px; top: 50%; color: var(--red); font-family: var(--sans); font-size: 24px; line-height: 1; transform: translateY(-50%); }
details[open] summary::after { content: "–"; }
details .ans { padding: 0 48px 24px 0; color: rgba(17, 17, 17, .72); font-size: 15px; line-height: 1.5; }
details .ans b { color: var(--black); font-weight: 700; }

.spec { width: 100%; margin: 26px 0; border-collapse: collapse; }
.spec th,
.spec td { padding: 15px 0; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
.spec th { width: 28%; color: var(--red); font-size: 10px; font-weight: 700; }
.spec td { color: var(--black); font-size: 14px; line-height: 1.5; font-weight: 700; }
.spec tr:first-child th,
.spec tr:first-child td { border-top: 2px solid var(--black); }

footer { width: 100%; max-width: none; margin-top: 0; padding: 48px max(32px, calc((100% - 1376px) / 2)) 42px; border-top: 1px solid var(--black); background: var(--black); color: var(--paper); }
.foot-in { width: min(1440px, 100%); margin: 0 auto; display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: 24px; }
.foot-in > div:first-child { grid-column: 1 / span 5; }
.foot-in > div:last-child { grid-column: 9 / -1; }
footer .big { margin: 0 0 14px; color: var(--paper); font-family: var(--sans); font-size: 32px; line-height: 1; font-weight: 700; }
footer .big em { color: var(--red); font-family: var(--sans); font-size: .55em; }
footer .sm { color: rgba(242, 239, 230, .62); font-size: 10px; line-height: 1.6; font-weight: 700; }
footer .sm[style] { text-align: left !important; }
footer a { color: var(--paper); border: 0; }
footer a:hover { color: var(--red); }
.foot-rule { width: min(1440px, 100%); margin: 40px auto 0; padding-top: 16px; border-top: 1px solid rgba(242, 239, 230, .35); display: flex; flex-wrap: wrap; gap: 24px; justify-content: space-between; color: rgba(242, 239, 230, .5); font-size: 10px; font-weight: 700; }

@media (max-width: 980px) {
  .topbar-in,
  .layout { width: calc(100% - 40px); column-gap: 16px; }
  .topbar-in { min-height: 64px; }
  .brand { grid-column: 1 / span 5; }
  .topbar .tag { display: none; }
  .topbar .home { grid-column: 8 / span 1; }
  .topbar .gh { grid-column: 9 / -1; }
  .layout { display: block; padding-bottom: 72px; }
  .side { display: none; }
  main { width: 100%; }
  .hero { margin: 0 -20px; padding: 58px 20px 32px; }
}

@media (max-width: 820px) {
  .grid-2,
  .grid-3 { grid-template-columns: 1fr; gap: 0; }
  .grid-2 > *,
  .grid-3 > * { grid-column: auto; }
  .feat { grid-template-columns: 1fr; gap: 0; }
  .feat li:nth-child(2n) { padding-left: 0; }
  .lights { grid-template-columns: 1fr; gap: 0; }
}

@media (max-width: 600px) {
  .topbar-in,
  .layout { width: calc(100% - 32px); }
  .topbar-in { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 10px; padding: 12px 0; }
  .brand { flex: 1 1 auto; min-width: 0; }
  .topbar .home,
  .topbar .gh { flex: 0 0 auto; }
  .hero h1 { max-width: none; font-size: 64px; }
  .hero .lede { font-size: 16px; }
  .hero-foot { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; font-size: 9px; }
  section { padding-top: 76px; }
  .sec-head { margin-bottom: 42px; }
  .sec-head h2 { max-width: none; font-size: 3.5rem; }
  h3.sub { margin-top: 54px; font-size: 20px; }
  .term pre { font-size: 11px; }
  .flow .item { grid-template-columns: 34px minmax(0, 1fr); gap: 12px; }
  .spec th { width: 34%; }
  .spec td { word-break: break-word; }
  footer { padding-right: 16px; padding-left: 16px; }
  .hero { margin: 0; padding: 58px 0 32px; }
  .foot-in > div:first-child,
  .foot-in > div:last-child { grid-column: 1 / -1; }
  .foot-in { grid-template-columns: 1fr; gap: 0; }
  .foot-in > div:last-child { margin-top: 24px; }
  .foot-rule { justify-content: flex-start; gap: 12px; }
}