/* AI Lab for K12 flipbook.
   Layout: a dark "AI stage" (network canvas, glows) holds a paper book; pages are fixed 560x780 design px,
   scaled with --s. The stage is deliberately single-theme dark; pages carry their own paper/night palettes. */
:root {
  --night: #050a15;
  --night-2: #0a1222;
  --night-3: #0f1a30;
  --nline: rgba(148, 178, 220, .14);
  --nline-2: rgba(148, 178, 220, .26);
  --nink: #eef3fb;
  --nmuted: #98abc6;
  --cyan: #2fd4c4;
  --sky: #5b9dff;
  --grad: linear-gradient(100deg, #34e0cf 0%, #5b9dff 62%, #8ea8ff 100%);
  --rainbow: linear-gradient(90deg, #e1393f 0%, #f08a24 22%, #f2c230 40%, #29a96b 58%, #0b8f86 72%, #1c5fd8 86%, #3a3db0 100%);

  --paper: #fbfcfe;
  --paper-2: #eef3f9;
  --ink: #0e1a2b;
  --muted: #55657a;
  --rule: #dce4ee;
  --accent: #1c5fd8;
  --accent-soft: #e4edfc;
  --teal: #0b8f86;
  --teal-soft: #dff4f1;
  --blue: #1c5fd8;
  --blue-soft: #e4edfc;
  --indigo: #3a3db0;
  --indigo-soft: #e9e9f9;

  --display: "Lexend", "Be Vietnam Pro", system-ui, sans-serif;
  --body: "Be Vietnam Pro", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, Menlo, monospace;
  color-scheme: dark;
}
*, *::before, *::after { box-sizing: border-box; }
html, body { height: 100%; }
body { margin: 0; background: var(--night); color: var(--nink); font-family: var(--body); -webkit-font-smoothing: antialiased;
  display: grid; grid-template-rows: auto minmax(0, 1fr) auto; overflow: hidden; }
button { font: inherit; }
img { display: block; max-width: 100%; }
[hidden] { display: none !important; }
:focus-visible { outline: 2px solid var(--cyan); outline-offset: 2px; }

/* ---------- stage ---------- */
.stage-net { position: fixed; inset: 0; width: 100%; height: 100%; opacity: .5; z-index: 0; pointer-events: none; }
.stage-glow { position: fixed; inset: 0; z-index: 0; pointer-events: none;
  background: radial-gradient(900px 520px at 78% 8%, rgba(47, 212, 196, .13), transparent 60%),
              radial-gradient(900px 560px at 10% 95%, rgba(91, 157, 255, .13), transparent 60%); }
.topbar { position: relative; z-index: 3; display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 10px clamp(12px, 3vw, 24px); border-bottom: 1px solid var(--nline); background: rgba(5, 10, 21, .6);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); }
.topbar::before { content: ""; position: absolute; top: 0; left: 0; right: 0; height: 2px; background: var(--rainbow); }
.tb-brand { display: flex; align-items: center; gap: 12px; text-decoration: none; color: inherit; min-width: 0; }
.tb-brand img { height: 24px; width: auto; flex: none; }
.tb-name { border-left: 1px solid var(--nline-2); padding-left: 12px; line-height: 1.25; min-width: 0; }
.tb-name b { display: block; font-family: var(--display); font-weight: 600; font-size: 13.5px; color: #fff; }
.tb-name span { font-size: 11px; color: var(--nmuted); white-space: nowrap; }
.tb-actions { display: flex; align-items: center; gap: 8px; flex: none; }
.tb-btn { display: inline-flex; align-items: center; gap: 7px; padding: 8px 13px; border-radius: 999px; border: 1px solid var(--nline-2);
  background: rgba(255, 255, 255, .04); color: var(--nink); font-size: 13px; cursor: pointer; }
.tb-btn:hover { border-color: var(--cyan); }
.tb-btn svg { width: 16px; height: 16px; }
.tb-cta { padding: 9px 16px; border-radius: 999px; border: 0; background: var(--grad); color: #04101c; font-family: var(--display);
  font-weight: 600; font-size: 13px; cursor: pointer; box-shadow: 0 8px 26px rgba(47, 212, 196, .25); }
.tb-cta:hover { box-shadow: 0 10px 32px rgba(91, 157, 255, .35); }

.stage { position: relative; z-index: 1; display: grid; place-items: center; padding: 18px 20px; min-height: 0; overflow: hidden; }
.book-fit { position: relative; max-width: 100%; }
.book-fit::before { content: ""; position: absolute; left: 6%; right: 6%; bottom: -14px; height: 40px; border-radius: 50%;
  background: radial-gradient(closest-side, rgba(0, 0, 0, .55), transparent); filter: blur(6px); z-index: -1; }
.book { --s: 1; }
.book:not(.ready) { visibility: hidden; }
.book:not(.ready) .page { position: absolute; left: 0; top: 0; width: 560px; height: 780px; }
.loading { position: absolute; inset: auto 0 50% 0; text-align: center; font-family: var(--mono); font-size: 12px; color: var(--nmuted); letter-spacing: .1em; }

.dock { position: relative; z-index: 3; display: flex; align-items: center; justify-content: center; flex-wrap: wrap; gap: 8px;
  padding: 10px 14px; border-top: 1px solid var(--nline); background: rgba(5, 10, 21, .6);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); }
.dk-btn { width: 38px; height: 38px; border-radius: 11px; border: 1px solid var(--nline-2); background: rgba(255, 255, 255, .04);
  color: var(--nink); display: grid; place-items: center; cursor: pointer; flex: none; }
.dk-btn:hover { border-color: var(--cyan); }
.dk-btn:disabled { opacity: .35; cursor: default; border-color: var(--nline-2); }
.dk-btn svg { width: 18px; height: 18px; }
.dk-ind { font-family: var(--mono); font-size: 12px; color: var(--nink); min-width: 128px; text-align: center; font-variant-numeric: tabular-nums; }
.dk-sep { width: 1px; height: 24px; background: var(--nline-2); }
.dk-grades { display: inline-flex; align-items: center; gap: 4px; }
.dk-lbl { font-family: var(--mono); font-size: 10px; letter-spacing: .12em; text-transform: uppercase; color: var(--nmuted); margin-right: 4px; }
.dchip { --cc: #5fe0d4; width: 30px; height: 30px; border-radius: 9px; border: 1px solid var(--nline-2); background: transparent; color: var(--cc);
  font-family: var(--display); font-weight: 600; font-size: 12.5px; cursor: pointer; font-variant-numeric: tabular-nums; }
.dchip.lv-thcs { --cc: #86b4ff; }
.dchip.lv-thpt { --cc: #aeb0ff; }
.dchip:hover { border-color: var(--cc); }
.dchip.on { background: var(--cc); border-color: var(--cc); color: #04101c; }

.drawer { position: fixed; z-index: 10; top: 0; right: 0; bottom: 0; width: min(360px, 92vw); padding: 16px; overflow-y: auto;
  background: rgba(8, 14, 28, .97); border-left: 1px solid var(--nline-2); box-shadow: -30px 0 80px rgba(0, 0, 0, .5); }
.dr-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 10px; }
.dr-head b { font-family: var(--display); font-size: 16px; color: #fff; }
.dr-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 2px; }
.dr-list button { width: 100%; display: flex; gap: 14px; align-items: baseline; text-align: left; padding: 9px 10px; border-radius: 9px;
  background: none; border: 0; color: var(--nink); font-size: 14px; cursor: pointer; }
.dr-list button::before { content: attr(data-pg); font-family: var(--mono); font-size: 11px; color: var(--cyan); flex: none; width: 1.8em; }
.dr-list button:hover { background: rgba(255, 255, 255, .06); }
.dr-list button.on { background: rgba(47, 212, 196, .1); color: #fff; }

.zoom { position: fixed; inset: 0; z-index: 20; background: rgba(3, 6, 14, .94); display: grid; grid-template-rows: auto minmax(0, 1fr); }
.zm-bar { display: flex; align-items: center; justify-content: space-between; padding: 10px 16px; border-bottom: 1px solid var(--nline); font-family: var(--mono); font-size: 12px; color: var(--nmuted); letter-spacing: .08em; text-transform: uppercase; }
.zm-body { overflow: auto; padding: 20px; display: flex; flex-direction: column; align-items: flex-start; gap: 20px; }
.zm-body > .zm-page { margin-inline: auto; }
.zoom .zm-page { position: relative !important; flex: none; width: calc(560px * var(--s)); height: calc(780px * var(--s)); border-radius: 6px; box-shadow: 0 20px 60px rgba(0, 0, 0, .5); }
@media (max-width: 720px) {
  .tb-name span { display: none; }
  .tb-btn span { display: none; }
  .tb-btn { padding: 8px; }
  .dk-grades, .dk-sep { display: none; }
  .dk-ind { min-width: 110px; }
  .stage { padding: 10px; }
}
@media (max-width: 400px) { .tb-name { display: none; } }

/* ---------- page chrome ---------- */
.page { background: var(--paper); overflow: hidden; color: var(--ink); }
.gutter { position: absolute; top: 0; bottom: 0; width: 44px; pointer-events: none; z-index: 5; }
.page.--left .gutter { right: 0; background: linear-gradient(to left, rgba(10, 20, 40, .14), rgba(10, 20, 40, 0)); }
.page.--right .gutter { left: 0; background: linear-gradient(to right, rgba(10, 20, 40, .14), rgba(10, 20, 40, 0)); }
.pg-in { position: absolute; left: 0; top: 0; width: 560px; height: 780px; transform: scale(var(--s)); transform-origin: 0 0;
  display: flex; flex-direction: column; padding: 24px 36px 20px; font-family: var(--body); font-size: 12px; line-height: 1.5; }
.page:not(.dark) .pg-in::before { content: ""; position: absolute; top: 0; right: 0; width: 240px; height: 190px; pointer-events: none;
  background-image: radial-gradient(rgba(28, 95, 216, .22) 1px, transparent 1.3px); background-size: 12px 12px;
  -webkit-mask-image: radial-gradient(circle at 100% 0, #000 10%, transparent 70%); mask-image: radial-gradient(circle at 100% 0, #000 10%, transparent 70%); }
.pg-head { position: relative; display: flex; justify-content: space-between; gap: 12px; font-family: var(--mono); font-size: 8.5px;
  letter-spacing: .14em; text-transform: uppercase; color: var(--muted); padding-bottom: 9px; border-bottom: 1px solid var(--rule); }
.pg-head::after { content: ""; position: absolute; left: 0; bottom: -1px; width: 64px; height: 1px; background: var(--grad); }
.pg-body { position: relative; flex: 1 1 auto; min-height: 0; display: flex; flex-direction: column; padding-top: 16px; }
.pg-foot { display: flex; justify-content: space-between; font-family: var(--mono); font-size: 8.5px; letter-spacing: .1em; text-transform: uppercase;
  color: var(--muted); padding-top: 9px; margin-top: 10px; border-top: 1px solid var(--rule); }
.pg-n { color: var(--ink); }
.page.dark { background: radial-gradient(420px 300px at 90% 0%, rgba(47, 212, 196, .16), transparent 65%),
  radial-gradient(420px 320px at 0% 100%, rgba(91, 157, 255, .16), transparent 65%), var(--night); color: var(--nink); }
.page.dark .pg-in { color: var(--nink); }
.page.dark .pg-in::before { content: ""; position: absolute; inset: 0; pointer-events: none;
  background-image: linear-gradient(var(--nline) 1px, transparent 1px), linear-gradient(90deg, var(--nline) 1px, transparent 1px);
  background-size: 40px 40px; -webkit-mask-image: radial-gradient(ellipse 80% 60% at 60% 30%, #000 20%, transparent 75%);
  mask-image: radial-gradient(ellipse 80% 60% at 60% 30%, #000 20%, transparent 75%); opacity: .8; }
.page.dark .pg-head, .page.dark .pg-foot { color: var(--nmuted); border-color: var(--nline); }
.page.dark .pg-n { color: #fff; }
.page.dark .gutter { opacity: .6; }
.nodes { position: absolute; left: 0; top: 0; width: 560px; height: 260px; opacity: .55; pointer-events: none; }
.nodes .ln line { stroke: rgba(91, 157, 255, .4); stroke-width: 1; }
.nodes .dt circle { fill: var(--cyan); }
.page button { pointer-events: auto; }
.page button * { pointer-events: none; }

/* ---------- shared page components ---------- */
.kick { display: flex; align-items: center; gap: 8px; margin: 0; font-family: var(--mono); font-size: 9px; font-weight: 500; letter-spacing: .16em; text-transform: uppercase; color: var(--accent); }
.kick::before { content: ""; width: 16px; height: 1px; background: currentColor; }
.kick.sm { margin: 16px 0 8px; font-size: 8.5px; }
.kick-note { margin-left: auto; font-family: var(--body); font-size: 9.5px; font-weight: 400; letter-spacing: 0; text-transform: none; color: var(--muted, #6b7280); white-space: nowrap; }
.kick.on-dark { color: var(--cyan); }
.h2 { margin: 8px 0 12px; font-family: var(--display); font-weight: 600; font-size: 26px; line-height: 1.15; letter-spacing: -.02em; color: var(--ink); text-wrap: balance; }
.h2.sm { font-size: 19px; margin: 6px 0 6px; }
.h2.sm2 { font-size: 18px; margin: 16px 0 8px; }
.h2.on-dark { color: #fff; }
.lead { margin: 0; font-size: 12.5px; color: var(--muted); line-height: 1.6; }
.lead.on-dark { color: var(--nmuted); }
p { margin: 0; }
h3, h4 { margin: 0; font-family: var(--display); font-weight: 600; color: inherit; line-height: 1.3; }
ul, ol { margin: 0; padding: 0; list-style: none; }
.ico { width: 30px; height: 30px; border-radius: 8px; background: var(--accent-soft); color: var(--accent); display: grid; place-items: center; flex: none; }
.ico svg { width: 16px; height: 16px; }
.ico.dk { background: rgba(47, 212, 196, .12); color: var(--cyan); }
.checks { display: grid; gap: 7px; }
.checks li { display: flex; gap: 8px; align-items: flex-start; font-size: 11.5px; }
.checks svg { width: 15px; height: 15px; color: var(--teal); flex: none; margin-top: 1px; }
.ticks { display: grid; gap: 5px; margin-top: 6px; }
.ticks li { display: flex; gap: 6px; align-items: flex-start; font-size: 10.5px; line-height: 1.45; }
.ticks svg { width: 13px; height: 13px; color: var(--teal); flex: none; margin-top: 1px; }
.grad { background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.pulse { width: 7px; height: 7px; border-radius: 50%; background: var(--cyan); box-shadow: 0 0 0 4px rgba(47, 212, 196, .18); }
.lv-th { --c: var(--teal); --c-soft: var(--teal-soft); }
.lv-thcs { --c: var(--blue); --c-soft: var(--blue-soft); }
.lv-thpt { --c: var(--indigo); --c-soft: var(--indigo-soft); }

/* cover */
.cover .pg-in { padding: 30px 38px 26px; }
.cover .pg-body { padding-top: 0; }
.cv-top { position: relative; display: flex; justify-content: space-between; align-items: center; }
.cv-top img { height: 24px; width: auto; }
.cv-top span { font-family: var(--mono); font-size: 9px; letter-spacing: .16em; text-transform: uppercase; color: var(--nmuted); }
.cv-pill { position: relative; align-self: flex-start; display: inline-flex; align-items: center; gap: 8px; margin-top: 52px; padding: 5px 12px; border: 1px solid var(--nline-2); border-radius: 999px; background: rgba(255, 255, 255, .04); font-size: 11px; color: var(--nink); }
.cv-title { position: relative; margin: 16px 0 0; font-family: var(--display); font-weight: 700; font-size: 60px; line-height: 1; letter-spacing: -.035em; color: #fff; }
.cv-sub { position: relative; margin-top: 14px; font-size: 14.5px; line-height: 1.55; color: var(--nmuted); max-width: 430px; text-wrap: balance; }
.cv-fig { position: relative; margin: 24px 0 0; }
.cv-fig img { width: 100%; height: 250px; object-fit: cover; object-position: 50% 45%; border-radius: 14px; border: 1px solid var(--nline-2); box-shadow: 0 20px 60px rgba(0, 0, 0, .45), 0 0 0 4px rgba(47, 212, 196, .06); }
.cv-stats { position: relative; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); margin-top: 22px; padding-top: 14px; border-top: 1px solid var(--nline); }
.cv-stats li { display: grid; gap: 2px; padding-left: 12px; border-left: 1px solid var(--nline); }
.cv-stats li:first-child { padding-left: 0; border-left: 0; }
.cv-stats b { font-family: var(--display); font-weight: 600; font-size: 21px; color: #fff; letter-spacing: -.02em; }
.cv-stats span { font-size: 9.5px; color: var(--nmuted); }
.cv-for { position: relative; margin-top: auto; padding-top: 12px; border-top: 1px solid var(--nline); font-size: 11.5px; color: #d4dfee; }
.cv-hint { position: relative; margin-top: 6px; text-align: right; font-family: var(--mono); font-size: 8.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--cyan); }

/* toc */
.toc { display: grid; }
.toc-row { width: 100%; display: flex; align-items: baseline; gap: 14px; padding: 8px 2px; border: 0; border-bottom: 1px dashed var(--rule); background: none;
  font-family: var(--display); font-weight: 500; font-size: 14px; color: var(--ink); text-align: left; cursor: pointer; }
.toc-row::before { content: attr(data-pg); font-family: var(--mono); font-size: 10.5px; color: var(--accent); width: 1.9em; flex: none; }
.toc-row::after { content: "→"; margin-left: auto; color: var(--muted); font-size: 12px; }
.toc-row:hover { color: var(--accent); }
.gchips { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: 6px; }
.gchip { height: 30px; border-radius: 8px; border: 1px solid transparent; background: var(--c-soft); color: var(--c); font-family: var(--display); font-weight: 600; font-size: 11.5px; cursor: pointer; }
.gchip:hover { border-color: var(--c); }
.figs4 { margin-top: auto; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 8px; }
.figs4 div { padding: 10px 0 0; border-top: 2px solid var(--ink); display: grid; gap: 2px; }
.figs4 b { font-family: var(--display); font-weight: 600; font-size: 17px; letter-spacing: -.02em; }
.figs4 span { font-size: 9.5px; color: var(--muted); line-height: 1.35; }

/* audience */
.auds { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; }
.aud { padding: 14px; border-radius: 12px; border: 1px solid var(--rule); background: #fff; display: grid; gap: 6px; align-content: start; }
.aud h3 { font-size: 13.5px; }
.aud p { font-size: 11px; color: var(--muted); line-height: 1.5; }

/* about */
.mission { margin: 12px 0; padding: 12px 14px; border-radius: 12px; background: var(--night); color: var(--nink); display: grid; gap: 4px; }
.mission b { font-family: var(--display); font-size: 15px; color: #fff; }
.mission p { font-size: 10.8px; color: var(--nmuted); }
.caps { display: grid; gap: 9px; }
.cap { display: flex; gap: 10px; align-items: flex-start; }
.cap h3 { font-size: 12.5px; }
.cap p { font-size: 10.6px; color: var(--muted); line-height: 1.45; margin-top: 1px; }
.figs3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; margin-top: 12px; }
.figs3 div { border-top: 1px solid var(--rule); padding-top: 8px; display: grid; }
.figs3 b { font-family: var(--display); font-weight: 600; font-size: 24px; color: var(--accent); letter-spacing: -.03em; line-height: 1.1; }
.figs3 span { font-size: 10px; color: var(--muted); }
.partners { margin-top: auto; display: flex; flex-wrap: wrap; align-items: center; gap: 6px; }
.partners .kick { margin: 0 6px 0 0; }
.pt { font-family: var(--display); font-weight: 600; font-size: 11.5px; color: var(--muted); padding: 3px 10px; border: 1px solid var(--rule); border-radius: 999px; }

/* philosophy */
.philo li { display: grid; grid-template-columns: 26px minmax(0, 1fr); gap: 8px; padding: 6px 0; border-top: 1px solid var(--rule); }
.philo .pn { font-family: var(--mono); font-size: 10px; color: var(--accent); padding-top: 2px; }
.philo .from { font-size: 10.5px; color: var(--teal); font-weight: 500; }
.philo h3 { font-size: 13.5px; }
.philo p:last-child { font-size: 10.8px; color: var(--muted); line-height: 1.45; }
.arch { margin-top: 8px; padding: 10px 12px; border-radius: 14px; background: radial-gradient(260px 160px at 100% 0%, rgba(91, 157, 255, .2), transparent 65%), var(--night); color: var(--nink); display: grid; gap: 6px; }
.arch-t { font-family: var(--display); font-weight: 600; font-size: 13px; color: #fff; margin-bottom: 2px; }
.tiers { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 6px; }
.tier { border-radius: 9px; padding: 8px 10px; display: grid; gap: 1px; }
.tier b { font-family: var(--display); font-weight: 600; font-size: 11px; color: #fff; line-height: 1.3; }
.tier span { font-size: 9.5px; color: rgba(255, 255, 255, .82); }
.tier.th { background: linear-gradient(135deg, #0b8f86, #0c6e74); }
.tier.tsec { background: linear-gradient(135deg, #1c5fd8, #3a3db0); }
.layer { display: flex; gap: 9px; align-items: center; padding: 5px 9px; border-radius: 9px; background: rgba(255, 255, 255, .04); border: 1px solid var(--nline); }
.layer .ico { width: 26px; height: 26px; }
.layer b { display: block; font-family: var(--display); font-weight: 600; font-size: 11px; color: #fff; }
.layer span { font-size: 9.8px; color: var(--nmuted); }
.pills { margin-top: 8px; display: grid; gap: 4px; }
.pills li { font-size: 10px; padding: 4px 9px; border: 1px dashed var(--rule); border-radius: 8px; }

/* roadmap */
.stair { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: 5px; align-items: end; height: 190px; margin: 16px 0 4px; }
.bar { height: var(--h); border: 0; border-radius: 6px 6px 2px 2px; cursor: pointer; color: #fff; font-family: var(--display); font-weight: 600; font-size: 10.5px;
  display: flex; align-items: flex-end; justify-content: center; padding: 0 0 5px; background: linear-gradient(180deg, var(--c), color-mix(in srgb, var(--c) 45%, #fff)); }
.bar:hover { filter: brightness(1.12); }
.stair-cap { text-align: center; font-family: var(--mono); font-size: 8.5px; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); }
.lvls { display: grid; gap: 8px; margin-top: 14px; }
.lvl { padding: 9px 12px; border-radius: 10px; border: 1px solid var(--rule); border-left: 3px solid var(--c); background: #fff; }
.lvl-h { display: flex; gap: 8px; align-items: baseline; }
.lvl-h b { font-family: var(--display); font-weight: 600; font-size: 13px; }
.lvl-h span { font-size: 10px; color: var(--muted); }
.lvl-h em { margin-left: auto; font-style: normal; font-family: var(--mono); font-size: 10px; color: var(--c); }
.lvl p { font-size: 10.8px; color: var(--muted); margin-top: 2px; line-height: 1.45; }
.flow { margin-top: auto; display: flex; justify-content: center; align-items: center; gap: 8px; }
.flow span { font-family: var(--display); font-weight: 500; font-size: 11.5px; padding: 4px 12px; border-radius: 999px; border: 1px solid var(--rule); background: #fff; }
.flow i { width: 28px; height: 2px; border-radius: 2px; background: linear-gradient(90deg, var(--teal), var(--blue)); }

/* AI lesson demo */
.console { position: relative; margin-top: 4px; border-radius: 12px; border: 1px solid var(--nline-2); overflow: hidden;
  background: linear-gradient(180deg, rgba(18, 30, 54, .95), rgba(9, 16, 31, .95)); box-shadow: 0 24px 60px rgba(0, 0, 0, .45); }
.console::before { content: ""; position: absolute; top: 0; left: 12%; right: 12%; height: 1px; background: linear-gradient(90deg, transparent, rgba(91, 157, 255, .9), transparent); }
.c-bar { display: flex; align-items: center; gap: 8px; padding: 8px 12px; border-bottom: 1px solid var(--nline); }
.c-dots { display: inline-flex; gap: 4px; }
.c-dots i { width: 7px; height: 7px; border-radius: 50%; background: rgba(255, 255, 255, .18); }
.c-title { flex: 1; display: inline-flex; align-items: center; gap: 5px; font-family: var(--display); font-weight: 500; font-size: 11.5px; color: #fff; }
.c-title svg { width: 12px; height: 12px; color: var(--cyan); }
.c-badge { font-family: var(--mono); font-size: 7.5px; letter-spacing: .08em; text-transform: uppercase; padding: 2px 6px; border: 1px solid var(--nline-2); border-radius: 5px; color: var(--nmuted); }
.c-body { padding: 10px 12px; display: grid; gap: 7px; }
.c-ctx { display: flex; flex-wrap: wrap; gap: 4px; }
.c-ctx span { font-size: 9px; padding: 2px 7px; border-radius: 5px; background: rgba(91, 157, 255, .14); color: #c2d6ff; }
.c-user { justify-self: end; max-width: 86%; background: rgba(255, 255, 255, .07); border: 1px solid var(--nline); border-radius: 10px 10px 3px 10px; padding: 6px 10px; font-size: 10.5px; color: #e8eff9; }
.c-ai { display: flex; gap: 7px; align-items: center; font-size: 10.5px; color: #cfdcf0; }
.c-av { width: 18px; height: 18px; border-radius: 5px; background: var(--grad); color: #04101c; font-family: var(--mono); font-size: 7.5px; display: grid; place-items: center; flex: none; }
.c-steps { display: grid; gap: 5px; }
.c-steps li { display: grid; grid-template-columns: 18px minmax(0, 1fr); gap: 8px; padding: 8px 9px; border-radius: 8px; border: 1px solid var(--nline); background: rgba(255, 255, 255, .03); }
.c-dot { width: 18px; height: 18px; border-radius: 50%; border: 1px solid rgba(47, 212, 196, .55); color: var(--cyan); font-family: var(--mono); font-size: 8.5px; display: grid; place-items: center; }
.c-h { display: flex; gap: 6px; align-items: baseline; }
.c-h b { font-family: var(--display); font-weight: 600; font-size: 11.8px; color: #fff; }
.c-h span { font-family: var(--mono); font-size: 8px; color: var(--nmuted); }
.c-h em { margin-left: auto; font-style: normal; font-family: var(--mono); font-size: 8.5px; color: var(--cyan); white-space: nowrap; }
.c-d { font-size: 10.5px; color: #a8bad2; line-height: 1.4; }
.c-status { display: flex; gap: 6px; align-items: center; font-size: 10px; color: #ffd58a; }
.led { width: 7px; height: 7px; border-radius: 50%; background: #ffc24b; box-shadow: 0 0 8px rgba(255, 194, 75, .8); }
.how { position: relative; margin-top: auto; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; padding-top: 12px; }
.how li { padding: 10px; border-radius: 10px; border: 1px solid var(--nline); background: rgba(255, 255, 255, .03); }
.how b { display: block; font-family: var(--display); font-size: 18px; font-weight: 700; background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.how span { font-size: 10.5px; color: var(--nmuted); line-height: 1.4; display: block; }

/* grade spread: left */
.grade-l .pg-body { padding-top: 0; }
.g-band { position: relative; height: 205px; margin: 0 -36px; overflow: hidden; flex: none; }
.g-band img { width: 100%; height: 100%; object-fit: cover; }
.g-ov { position: absolute; inset: 0; background: linear-gradient(180deg, rgba(5, 10, 21, 0) 35%, rgba(5, 10, 21, .78)); }
.g-num { position: absolute; left: 36px; bottom: 14px; font-family: var(--display); font-weight: 700; font-size: 60px; line-height: .9; letter-spacing: -.04em; color: #fff; font-variant-numeric: tabular-nums; }
.g-num span { display: block; font-size: 14px; font-weight: 600; letter-spacing: 0; margin-bottom: 4px; opacity: .9; }
.g-lv { position: absolute; right: 36px; bottom: 18px; font-size: 10px; font-weight: 500; padding: 4px 10px; border-radius: 999px; background: var(--c); color: #fff; }
.g-main { flex: 1 1 auto; min-height: 0; display: flex; flex-direction: column; padding-top: 14px; }
.g-theme { margin: 0; font-family: var(--display); font-weight: 600; font-size: 21px; line-height: 1.2; letter-spacing: -.015em; text-wrap: balance; }
.g-desc { margin-top: 6px; font-size: 11.5px; color: var(--muted); line-height: 1.55; }
.g-facts { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 10px; }
.g-facts span { font-size: 9.5px; font-weight: 500; padding: 3px 9px; border-radius: 999px; background: var(--c-soft); color: var(--c); }
.grade-l .kick { color: var(--c); }
.feats { flex: 1 1 auto; min-height: 0; overflow: hidden; display: grid; gap: .7em; align-content: start; font-size: 13px; }
.feat { display: grid; grid-template-columns: 8.4em minmax(0, 1fr); gap: .9em; padding: .7em; border: 1px solid var(--rule); border-radius: 10px; background: #fff; }
.feat img { width: 8.4em; height: 6.3em; object-fit: cover; border-radius: 7px; }
.f-meta { display: flex; gap: .5em; align-items: center; font-family: var(--mono); font-size: .78em; color: var(--c); }
.code { background: var(--paper-2); color: var(--ink); padding: 1px 5px; border-radius: 4px; }
.feat h3 { font-size: 1.12em; margin: .15em 0 .2em; }
.f-c { font-size: .9em; color: var(--muted); line-height: 1.45; }
.f-app { font-size: .84em; color: var(--c); font-weight: 500; margin-top: .25em; }

/* grade spread: right */
.grade-r .kick { color: var(--c); }
.orient { font-size: 10.5px; color: var(--muted); margin-bottom: 10px; line-height: 1.5; }
.orient b { color: var(--ink); font-weight: 600; }
.terms { flex: 1 1 auto; min-height: 0; overflow: hidden; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 14px; font-size: 13px; align-content: start; }
.term { min-width: 0; }
.term-h { display: flex; justify-content: space-between; align-items: baseline; font-family: var(--display); font-weight: 600; font-size: 1.08em; padding-bottom: .45em; border-bottom: 2px solid var(--c); }
.term-h span { font-family: var(--mono); font-weight: 500; font-size: .74em; color: var(--muted); }
.rm li { display: grid; grid-template-columns: 2.5em minmax(0, 1fr); gap: .5em; padding: .5em 0; border-bottom: 1px solid var(--rule); }
.r-t { font-family: var(--mono); font-size: .8em; color: var(--c); padding-top: .15em; font-variant-numeric: tabular-nums; }
.rm h4 { font-size: .98em; line-height: 1.3; }
.rm p { font-size: .85em; color: var(--muted); line-height: 1.4; margin-top: .1em; }
.rm .r-app { color: var(--c); font-weight: 500; }
.note { margin-top: 8px; font-size: 9.5px; color: var(--muted); }

/* platform & packs */
.pf { display: grid; grid-template-columns: minmax(0, 1.08fr) minmax(0, 1fr); gap: 14px; align-items: center; margin-top: 8px; padding-top: 12px; border-top: 1px solid var(--rule); }
.pf:first-of-type { border-top: 0; }
.pf h3 { font-size: 15px; margin-bottom: 5px; }
.pf p { font-size: 11.5px; color: var(--muted); line-height: 1.5; }
.win { border-radius: 10px; border: 1px solid var(--rule); overflow: hidden; background: #fff; box-shadow: 0 14px 34px rgba(14, 26, 43, .14); }
.win-bar { display: flex; align-items: center; gap: 8px; padding: 5px 8px; background: var(--paper-2); border-bottom: 1px solid var(--rule); font-family: var(--mono); font-size: 8px; color: var(--muted); }
.win .c-dots i { width: 6px; height: 6px; background: var(--rule); }
.win img { width: 100%; height: 205px; object-fit: cover; object-position: top center; }
.roles { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px; }
.role { padding: 13px; border-radius: 10px; border: 1px solid var(--rule); background: #fff; display: grid; gap: 5px; align-content: start; }
.role h3 { font-size: 13.5px; }
.role p { font-size: 11.3px; color: var(--muted); line-height: 1.45; }
.packs { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px; }
.pack { padding: 14px; border-radius: 12px; border: 1px solid var(--rule); background: #fff; display: grid; gap: 4px; align-content: start; }
.pack.hi { border: 1.5px solid transparent; background: linear-gradient(#fff, #fff) padding-box, linear-gradient(120deg, #2fd4c4, #5b9dff) border-box; box-shadow: 0 12px 30px rgba(28, 95, 216, .12); }
.pack-k { font-family: var(--mono); font-size: 8.5px; letter-spacing: .12em; text-transform: uppercase; color: var(--accent); }
.pack h3 { font-size: 14px; }
.pack > p:not(.pack-k) { font-size: 11.3px; color: var(--muted); }
.pack .ticks { margin-top: 6px; padding-top: 8px; border-top: 1px solid var(--rule); }

/* security */
.sec-grid { position: relative; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px; margin-top: 14px; }
.sec { display: flex; gap: 10px; align-items: flex-start; padding: 12px; border-radius: 10px; border: 1px solid var(--nline); background: rgba(255, 255, 255, .03); }
.sec .ico { width: 26px; height: 26px; }
.sec h3 { font-size: 12.5px; color: #fff; }
.sec p { font-size: 11px; color: var(--nmuted); line-height: 1.4; margin-top: 1px; }
.longt { position: relative; margin-top: auto; display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 8px; }
.longt li { padding: 9px 10px; border-radius: 0 0 10px 10px; border-top: 2px solid var(--cyan); background: rgba(255, 255, 255, .04); }
.longt b { display: block; font-family: var(--display); font-weight: 600; font-size: 11px; color: #fff; }
.longt span { font-size: 9.5px; color: var(--nmuted); }

/* why */
.cmp { border-radius: 12px; border: 1px solid var(--rule); overflow: hidden; background: #fff; }
.cmp-r { display: grid; grid-template-columns: minmax(0, .5fr) minmax(0, 1.3fr) minmax(0, 1.15fr); border-top: 1px solid var(--rule); }
.cmp-r > span { padding: 9px 10px; font-size: 11.3px; line-height: 1.45; }
.cmp-h { border-top: 0; background: var(--paper-2); }
.cmp-h > span { font-family: var(--display); font-weight: 600; }
.cmp-h .us { color: var(--accent); }
.cmp .us { background: color-mix(in srgb, var(--accent-soft) 60%, #fff); }
.cmp .us svg { width: 12px; height: 12px; color: var(--teal); margin-right: 5px; vertical-align: -1px; }
.cmp .k { font-family: var(--display); font-weight: 600; }
.cmp .them { color: var(--muted); }
.tl { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; }
.tl li { position: relative; padding-top: 18px; display: grid; gap: 3px; align-content: start; }
.tl li::before { content: ""; position: absolute; top: 2px; left: 0; width: 11px; height: 11px; border-radius: 50%; border: 2.5px solid var(--accent); background: var(--paper); }
.tl li::after { content: ""; position: absolute; top: 7px; left: 16px; right: -6px; height: 2px; background: linear-gradient(90deg, var(--accent), rgba(28, 95, 216, .1)); }
.tl li:last-child::after { display: none; }
.tl-n { font-family: var(--mono); font-size: 8.5px; color: var(--accent); }
.tl h3 { font-size: 12.5px; }
.tl p { font-size: 10.5px; color: var(--muted); line-height: 1.45; }

/* back cover */
.back .pg-in { padding: 34px 38px 26px; }
.back .pg-body { padding-top: 110px; }
.bk-title { position: relative; margin: 10px 0 14px; font-family: var(--display); font-weight: 700; font-size: 36px; line-height: 1.1; letter-spacing: -.03em; color: #fff; }
.bk-mail { position: relative; margin: 26px 0 22px; display: grid; gap: 6px; }
.bk-mail .kick { margin: 0; }
.addr { font-family: var(--display); font-weight: 600; font-size: 26px; color: #fff; text-decoration: none; justify-self: start; border-bottom: 1px solid var(--cyan); }
.bk-off { position: relative; display: grid; gap: 10px; }
.bk-glob { font-family: var(--display); font-weight: 600; font-size: 12.5px; color: #fff; padding-bottom: 8px; border-bottom: 1px solid var(--nline); }
.bk-off b { display: block; font-family: var(--display); font-weight: 600; font-size: 12px; color: #fff; }
.bk-off span { font-size: 10.5px; color: var(--nmuted); }
.bk-foot { position: relative; margin-top: auto; display: flex; justify-content: space-between; align-items: center; gap: 10px; padding-top: 12px; border-top: 1px solid var(--nline); }
.bk-foot img { height: 22px; width: auto; }
.bk-foot span { font-size: 9px; color: var(--nmuted); }

.nw { white-space: nowrap; }
.strip { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 8px; margin-top: 12px; }
.strip figure { margin: 0; position: relative; }
.strip img { width: 100%; height: auto; aspect-ratio: 4 / 3; object-fit: cover; border-radius: 9px; }
.strip figcaption { position: absolute; left: 6px; bottom: 6px; font-family: var(--display); font-weight: 600; font-size: 9.5px; color: #fff; padding: 2px 7px; border-radius: 999px; background: rgba(5, 10, 21, .65); }
.cta-box { margin-top: auto; display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 14px 16px; border-radius: 14px; background: radial-gradient(260px 120px at 100% 0%, rgba(47, 212, 196, .22), transparent 70%), var(--night); color: var(--nink); }
.cta-box b { display: block; font-family: var(--display); font-weight: 600; font-size: 14px; color: #fff; }
.cta-box span { font-size: 10.5px; color: var(--nmuted); }
.cta-btn { flex: none; padding: 8px 14px; border-radius: 999px; border: 0; background: var(--grad); color: #04101c; font-family: var(--display); font-weight: 600; font-size: 11.5px; cursor: pointer; }

/* language switch */
.lang-sw { display: inline-flex; align-items: center; border: 1px solid var(--nline-2); border-radius: 999px; padding: 2px; background: rgba(255, 255, 255, .04); }
.lang-sw button { border: 0; background: transparent; color: var(--nmuted); font-family: var(--mono); font-size: 11.5px; letter-spacing: .06em; padding: 6px 10px; border-radius: 999px; cursor: pointer; }
.lang-sw button:hover { color: #fff; }
.lang-sw button[aria-pressed="true"] { background: var(--grad); color: #04101c; font-weight: 500; }
.nojs { display: none; position: relative; z-index: 2; padding: 32px 20px; text-align: center; color: var(--nink); font-size: 15px; line-height: 1.6; }
@media (max-width: 600px) { .tb-name { display: none; } .tb-cta { padding: 8px 12px; font-size: 12px; } }
@media (max-width: 430px) { .tb-cta { display: none; } }

/* centre the lone front / back cover in two-page view */
.book-fit { transition: transform .55s cubic-bezier(.3,.7,.2,1); }
.book-fit.at-cover { transform: translateX(-25%); }
.book-fit.at-back { transform: translateX(25%); }
.book-fit::before { transition: left .55s cubic-bezier(.3,.7,.2,1), right .55s cubic-bezier(.3,.7,.2,1); }
.book-fit.at-cover::before { left: 53%; right: 3%; }
.book-fit.at-back::before { left: 3%; right: 53%; }
.book-fit.instant, .book-fit.instant::before { transition: none; }
@media (prefers-reduced-motion: reduce) { .book-fit, .book-fit::before { transition: none; } }