/* noval download page.
   Layout: a night-desk hero (the app's newsroom, live) over manuscript-grid
   paper for the explanation, then a download "file card". Vermilion seal is
   the one warm accent; indigo ink for actions; desk colours only on the board. */
:root {
  --night: #0d1119;
  --night-2: #151c29;
  --night-line: #263044;
  --night-ink: #e8ecf3;
  --night-soft: #9aa5ba;

  --bg: #f5f6f8;
  --surface: #ffffff;
  --ink: #171c28;
  --ink-soft: #4f5869;
  --ink-faint: #8790a1;
  --rule: #dde1e8;
  --grid: rgba(196, 69, 47, .085);
  --accent: #2d4a8a;
  --accent-ink: #ffffff;
  --accent-wash: #e5ebf7;
  --seal: #c4452f;

  --display: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", Palatino, "Songti SC", "Noto Serif CJK SC", "Source Han Serif SC", "SimSun", Georgia, serif;
  --body: system-ui, -apple-system, "Segoe UI", "PingFang SC", "Hiragino Sans", "Microsoft YaHei", "Malgun Gothic", "Noto Sans CJK SC", sans-serif;
  --mono: "Cascadia Mono", "SFMono-Regular", Consolas, ui-monospace, monospace;
  --radius: 10px;
  --gutter: max(20px, env(safe-area-inset-left, 0px));
}
@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #10141c;
    --surface: #171d28;
    --ink: #e6eaf1;
    --ink-soft: #a3adbf;
    --ink-faint: #737d90;
    --rule: #283143;
    --grid: rgba(214, 95, 73, .10);
    --accent: #93acee;
    --accent-ink: #0d1322;
    --accent-wash: #1d2840;
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 76px; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 16px/1.65 var(--body); -webkit-font-smoothing: antialiased; }
h1, h2, h3 { margin: 0; line-height: 1.2; text-wrap: balance; }
p { margin: 0; }
a { color: var(--accent); }
img, svg { max-width: 100%; }
:focus-visible { outline: 2px solid var(--seal); outline-offset: 3px; border-radius: 4px; }
code { font-family: var(--mono); font-size: .88em; }
[hidden] { display: none !important; }
.sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.skip { position: absolute; left: -999px; top: 8px; background: var(--surface); padding: 8px 12px; z-index: 20; }
.skip:focus { left: 12px; }
.wrap { max-width: 1160px; margin: 0 auto; padding-left: var(--gutter); padding-right: max(20px, env(safe-area-inset-right, 0px)); }
.wrap.narrow { max-width: 820px; }

/* ---- header ---- */
.top { position: sticky; top: 0; z-index: 10; background: rgba(13, 17, 25, .95); backdrop-filter: blur(10px); border-bottom: 1px solid rgba(255,255,255,.06);
  padding-top: env(safe-area-inset-top, 0px); }
.top-row { display: flex; align-items: center; gap: 24px; min-height: 62px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--night-ink); text-decoration: none; }
.seal { width: 30px; height: 30px; border-radius: 7px; background: var(--seal); color: #fff; display: inline-grid; place-items: center;
  font: 600 18px/1 var(--display); box-shadow: inset 0 0 0 2px rgba(255,255,255,.18); flex: none; }
.seal.big { width: 64px; height: 64px; border-radius: 14px; font-size: 38px; }
.wordmark { font: 600 22px/1 var(--display); letter-spacing: .02em; }
.nav { display: flex; gap: 22px; margin-left: auto; }
.nav a { color: var(--night-soft); text-decoration: none; font-size: 15px; }
.nav a:hover { color: var(--night-ink); }
.lang select { background: transparent; color: var(--night-ink); border: 1px solid var(--night-line); border-radius: 8px; padding: 6px 10px; font: inherit; font-size: 14px; }
.lang select option { color: #111; }

/* ---- hero ---- */
.hero { background: radial-gradient(1200px 500px at 85% -10%, rgba(141,155,255,.16), transparent 60%),
  radial-gradient(800px 420px at 0% 100%, rgba(196,69,47,.14), transparent 60%), var(--night);
  color: var(--night-ink); padding-block: clamp(48px, 8vw, 96px) clamp(56px, 8vw, 104px); }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.08fr); gap: clamp(32px, 5vw, 64px); align-items: center; }
.eyebrow { color: #f0a493; font-size: 14px; letter-spacing: .04em; font-weight: 600; }
.hero h1 { font: 600 clamp(2.2rem, 4.6vw, 3.55rem)/1.08 var(--display); margin-top: 14px; letter-spacing: -.01em; }
.lede { color: #c3cbd9; font-size: clamp(1rem, 1.4vw, 1.12rem); margin-top: 20px; max-width: 34em; }
.cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 10px; padding: 13px 22px; border-radius: 10px; font-weight: 650;
  text-decoration: none; border: 1px solid transparent; transition: transform .15s, box-shadow .15s, background .15s; font-size: 16px; }
.btn.primary { background: var(--seal); color: #fff; box-shadow: 0 8px 24px -10px rgba(196,69,47,.8); }
.btn.primary:hover { transform: translateY(-1px); box-shadow: 0 12px 28px -10px rgba(196,69,47,.9); }
.btn.ghost { color: var(--night-ink); border-color: var(--night-line); }
.btn.ghost:hover { border-color: var(--night-soft); }
.btn.wide { width: 100%; }
.meta { color: var(--night-soft); font-size: 13.5px; margin-top: 16px; font-variant-numeric: tabular-nums; }

/* ---- the board (a replica of the app's newsroom) ---- */
.board { margin: 0; background: linear-gradient(180deg, #121927, #0b1019); border: 1px solid var(--night-line); border-radius: 16px;
  padding: 16px; box-shadow: 0 40px 80px -40px rgba(0,0,0,.8), inset 0 1px 0 rgba(255,255,255,.04); }
.board-head { display: flex; align-items: center; gap: 10px; font-size: 13px; color: var(--night-soft); padding: 2px 4px 12px; }
.board-title { font-weight: 600; color: var(--night-ink); }
.board-ch { margin-left: auto; font-variant-numeric: tabular-nums; }
.dot-live { width: 8px; height: 8px; border-radius: 50%; background: #e0644f; box-shadow: 0 0 0 0 rgba(224,100,79,.6); animation: pulse 1.8s infinite; }
@keyframes pulse { 70% { box-shadow: 0 0 0 8px rgba(224,100,79,0); } 100% { box-shadow: 0 0 0 0 rgba(224,100,79,0); } }
.desks { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 10px; position: relative; }
.desk { --c: #8d9bff; background: var(--night-2); border: 1px solid var(--night-line); border-radius: 12px; padding: 10px 10px 8px;
  display: grid; gap: 4px; min-width: 0; transition: border-color .3s, box-shadow .3s, transform .3s; }
.desk[data-on="1"] { border-color: var(--c); box-shadow: 0 0 0 1px var(--c), 0 0 28px -8px var(--c); transform: translateY(-2px); }
.desk-name { font-size: 12.5px; font-weight: 650; color: var(--night-ink); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.desk-role { font-size: 10.5px; color: var(--c); letter-spacing: .04em; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.desk svg { width: 100%; height: auto; display: block; }
.desk .avatar .glow { transition: opacity .3s; }
.desk[data-on="1"] .avatar .glow { opacity: .3; }
.desk[data-on="1"] .arm.a1 { animation: type .26s infinite alternate; }
.desk[data-on="1"] .arm.a2 { animation: type .26s .13s infinite alternate; }
.desk[data-on="1"] .codeline { animation: code 1.2s infinite; transform-origin: left; }
@keyframes type { to { transform: translateY(-2px); } }
@keyframes code { 0% { transform: scaleX(.2); } 60%, 100% { transform: scaleX(1); } }
.tally { border: 1px dashed var(--night-line); border-radius: 12px; padding: 12px; display: grid; align-content: center; gap: 2px; min-width: 0; }
.tally-n { font: 600 clamp(1.6rem, 2.6vw, 2.2rem)/1 var(--display); color: var(--night-ink); font-variant-numeric: tabular-nums; }
.tally-k { font-size: 11.5px; color: var(--night-soft); }
.tally-bar { height: 4px; border-radius: 2px; background: var(--night-line); overflow: hidden; margin-top: 8px; }
.tally-bar i { display: block; height: 100%; background: #e0644f; transition: width .6s; }
.paper-fly { position: absolute; left: 0; top: 0; width: 22px; height: 28px; border-radius: 3px; background: #f4efe2;
  box-shadow: 0 6px 16px rgba(0,0,0,.5), inset 0 -3px 0 var(--c); pointer-events: none; z-index: 2; }
.wire { list-style: none; margin: 12px 0 0; padding: 10px 12px; background: rgba(0,0,0,.25); border: 1px solid var(--night-line); border-radius: 10px;
  height: 112px; overflow: hidden; display: grid; gap: 6px; align-content: start; font-size: 12.5px;
  -webkit-mask-image: linear-gradient(#000 70%, transparent); mask-image: linear-gradient(#000 70%, transparent); }
.wire li { display: flex; gap: 8px; color: var(--night-soft); min-width: 0; animation: slide .4s ease-out; }
.wire li b { color: var(--c); font-weight: 600; flex: none; }
.wire li span { white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.wire time { color: #5f6a80; font-variant-numeric: tabular-nums; flex: none; }
@keyframes slide { from { transform: translateY(-6px); background: rgba(141,155,255,.12); } }

/* ---- works with ---- */
.works { background: #0a0e15; color: var(--night-soft); border-top: 1px solid var(--night-line); }
.works-row { display: flex; flex-wrap: wrap; gap: 10px 28px; align-items: center; padding-block: 18px; font-size: 14.5px; }
.works-k { color: #5f6a80; font-size: 12px; letter-spacing: .12em; text-transform: uppercase; }
.works-row span:not(.works-k) { color: var(--night-ink); font-weight: 550; }

/* ---- sections ---- */
.section { padding-block: clamp(64px, 9vw, 112px); }
.paper { background-color: var(--surface);
  background-image: linear-gradient(var(--grid) 1px, transparent 1px), linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 30px 30px; background-position: center top; border-bottom: 1px solid var(--rule); }
.sec-head { max-width: 760px; margin-bottom: 44px; }
.kicker { color: var(--seal); font-size: 13px; letter-spacing: .14em; text-transform: uppercase; font-weight: 650; }
.sec-head h2 { font: 600 clamp(1.8rem, 3.4vw, 2.6rem)/1.15 var(--display); margin-top: 12px; }
.sec-lede { color: var(--ink-soft); margin-top: 16px; font-size: 1.06rem; max-width: 40em; }

.track { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: 12px; counter-reset: s; }
.track li { position: relative; background: var(--surface); border: 1px solid var(--rule); border-radius: var(--radius); padding: 18px 16px 20px; display: grid; gap: 8px; align-content: start; }
.track li::after { content: ""; position: absolute; right: -9px; top: 30px; width: 6px; height: 6px; border-top: 2px solid var(--ink-faint); border-right: 2px solid var(--ink-faint); transform: rotate(45deg); }
.track li:last-child::after { display: none; }
.st-n { font: 600 13px/1 var(--mono); color: var(--ink-faint); }
.track h3 { font: 600 1.12rem/1.25 var(--display); }
.track p { color: var(--ink-soft); font-size: 14.5px; }
.stamp { position: absolute; top: 12px; right: 12px; color: var(--seal); border: 2px solid var(--seal); border-radius: 6px; padding: 1px 6px;
  font-size: 11px; font-weight: 700; letter-spacing: .06em; transform: rotate(8deg); opacity: .85; text-transform: uppercase; }

.loop { margin-top: 56px; display: grid; grid-template-columns: minmax(0, .9fr) minmax(0, 1.1fr); gap: 40px; align-items: start;
  background: var(--surface); border: 1px solid var(--rule); border-radius: 14px; padding: clamp(22px, 3.5vw, 36px); }
.loop h3 { font: 600 1.5rem/1.2 var(--display); }
.loop-copy p { color: var(--ink-soft); margin-top: 12px; }
.loop-steps { margin: 0; padding: 0; list-style: none; counter-reset: l; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px 20px; }
.loop-steps li { counter-increment: l; display: flex; gap: 10px; align-items: baseline; font-size: 15px; padding: 6px 0; border-bottom: 1px dashed var(--rule); }
.loop-steps li::before { content: counter(l, decimal-leading-zero); font: 600 12px/1 var(--mono); color: var(--ink-faint); flex: none; width: 22px; }
.loop-steps li.hot { color: var(--seal); font-weight: 600; }

.feats { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 0; border-top: 1px solid var(--rule); }
.feat { padding: 28px 28px 30px 0; border-bottom: 1px solid var(--rule); display: grid; gap: 10px; align-content: start; }
.feat:not(:nth-child(3n + 1)) { padding-left: 28px; border-left: 1px solid var(--rule); }
.feat h3 { font: 600 1.2rem/1.3 var(--display); display: flex; gap: 10px; align-items: center; }
.feat h3::before { content: ""; width: 10px; height: 10px; border-radius: 50%; background: var(--c); flex: none; box-shadow: 0 0 0 4px color-mix(in srgb, var(--c) 22%, transparent); }
.feat p { color: var(--ink-soft); font-size: 15px; }
.langs-line { margin-top: 28px; color: var(--ink-soft); font-size: 15px; }
.langs-line span { color: var(--ink-faint); margin-right: 6px; }

/* ---- download ---- */
.dl { background: var(--surface); border-block: 1px solid var(--rule); }
.dl-grid { display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(0, .8fr); gap: clamp(32px, 6vw, 72px); align-items: start; }
.dl h2 { font: 600 clamp(1.8rem, 3.4vw, 2.5rem)/1.15 var(--display); margin-top: 12px; }
.tabs { display: inline-flex; gap: 4px; padding: 4px; background: var(--bg); border: 1px solid var(--rule); border-radius: 10px; margin-top: 28px; }
.tabs button { font: inherit; font-size: 14.5px; font-weight: 600; border: 0; background: none; color: var(--ink-soft); padding: 8px 16px; border-radius: 7px; cursor: pointer; }
.tabs button[aria-selected="true"] { background: var(--surface); color: var(--ink); box-shadow: 0 1px 3px rgba(0,0,0,.12); }
.steps { list-style: none; margin: 26px 0 0; padding: 0; counter-reset: n; display: grid; gap: 18px; }
.steps li { counter-increment: n; display: grid; grid-template-columns: 36px 1fr; column-gap: 14px; color: var(--ink-soft); }
.steps li::before { content: counter(n); grid-row: span 2; width: 36px; height: 36px; border-radius: 50%; background: var(--accent-wash); color: var(--accent);
  display: grid; place-items: center; font-weight: 700; }
.steps li strong { color: var(--ink); display: block; }
.note { margin-top: 28px; padding: 14px 16px; border-left: 3px solid var(--seal); background: var(--bg); border-radius: 0 8px 8px 0; color: var(--ink-soft); font-size: 15px; }

.file { position: relative; background: var(--bg); border: 1px solid var(--rule); border-radius: 16px; padding: 28px; display: grid; gap: 14px; justify-items: start; }
.file-name { font: 600 1.6rem/1.2 var(--display); margin-top: 6px; }
.file-sub { color: var(--ink-soft); font-size: 15px; }
.file-meta { margin: 6px 0 0; width: 100%; display: grid; gap: 8px; font-size: 14px; }
.file-meta div { display: flex; justify-content: space-between; gap: 12px; border-bottom: 1px solid var(--rule); padding-bottom: 8px; }
.file-meta dt { color: var(--ink-faint); }
.file-meta dd { margin: 0; font-variant-numeric: tabular-nums; }
.file-meta .sha { display: grid; gap: 4px; }
.file-meta .sha code { font-size: 11.5px; overflow-wrap: anywhere; color: var(--ink-soft); }

/* ---- faq ---- */
.faq { display: grid; gap: 10px; }
.faq details { background: var(--surface); border: 1px solid var(--rule); border-radius: var(--radius); padding: 0 20px; }
.faq summary { cursor: pointer; padding: 18px 0; font-weight: 650; font-size: 1.05rem; list-style: none; display: flex; justify-content: space-between; gap: 16px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--seal); font-weight: 400; font-size: 1.4rem; line-height: 1; }
.faq details[open] summary::after { content: "–"; }
.faq details p { color: var(--ink-soft); padding-bottom: 18px; }

.foot { background: var(--night); color: var(--night-soft); padding-block: 28px calc(28px + env(safe-area-inset-bottom, 0px)); font-size: 14px; }
.foot-row { display: flex; flex-wrap: wrap; gap: 12px 24px; align-items: center; }
.foot .brand.small .wordmark { font-size: 18px; }
.foot-ver { margin-left: auto; font-variant-numeric: tabular-nums; }

/* ---- responsive ---- */
@media (max-width: 1020px) {
  .hero-grid, .dl-grid, .loop { grid-template-columns: 1fr; }
  .track { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .track li:nth-child(3)::after { display: none; }
  .feats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .feat:not(:nth-child(3n + 1)) { padding-left: 0; border-left: 0; }
  .feat:nth-child(2n) { padding-left: 24px; border-left: 1px solid var(--rule); }
}
@media (max-width: 720px) {
  .nav { display: none; }
  .lang { margin-left: auto; }
  .desks { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .track { grid-template-columns: 1fr; }
  .track li::after { display: none; }
  .loop-steps { grid-template-columns: 1fr; }
  .feats { grid-template-columns: 1fr; }
  .feat:nth-child(2n) { padding-left: 0; border-left: 0; }
  .feat { padding-right: 0; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}