/* Layout: frontier-lab restraint. Every section pairs its copy with a live, monochrome visual: the hero diagram, four step vignettes, a drift chart, an exploded view of the base, status bars, the calculator, a memory chart. Numbers that change roll digit by digit. The logo is the only colour. */
:root {
  --bg: #0A0A0A;
  --panel: #111111;
  --card: #151515;
  --line: rgba(255, 255, 255, 0.08);
  --line-2: rgba(255, 255, 255, 0.14);
  --fg: #FAFAFA;
  --fg-2: #A3A3A3;
  --fg-3: #6B6B6B;
  --sans: "Inter", system-ui, -apple-system, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --word: "Outfit", "Inter", system-ui, sans-serif;
  --roll: cubic-bezier(0.16, 1, 0.3, 1);
  --move: cubic-bezier(0.65, 0, 0.35, 1);
  color-scheme: dark;
}
* { box-sizing: border-box; }
html { background: var(--bg); }
body { background: var(--bg); color: var(--fg); font: 400 15px/1.55 var(--sans); font-optical-sizing: auto; -webkit-font-smoothing: antialiased; overflow-x: hidden; margin: 0; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; }
:focus-visible { outline: 2px solid var(--fg); outline-offset: 3px; border-radius: 8px; }
[hidden] { display: none !important; }
.wrap { width: 100%; max-width: 1240px; margin-inline: auto; padding-left: max(16px, env(safe-area-inset-left, 0px)); padding-right: max(16px, env(safe-area-inset-right, 0px)); }
.mono { font-family: var(--mono); }
.tab { font-variant-numeric: tabular-nums; }
body::before { content: ""; position: fixed; inset: 0 0 auto; height: env(safe-area-inset-top, 0px); z-index: 30; background: var(--bg); }

/* rolling digits */
.roll { position: relative; display: inline-flex; vertical-align: top; height: var(--lh, 1.2em); line-height: var(--lh, 1.2em); font-variant-numeric: tabular-nums; white-space: nowrap; }
.rl { display: inline-flex; }
.rd, .rc { display: inline-block; height: var(--lh, 1.2em); }
.rd { overflow: hidden; -webkit-mask-image: linear-gradient(transparent, #000 18%, #000 82%, transparent); mask-image: linear-gradient(transparent, #000 18%, #000 82%, transparent); }
.rs { display: flex; flex-direction: column; transition: transform 0.6s var(--roll); }
.rs span { display: block; height: var(--lh, 1.2em); text-align: center; }
.sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.rcol, .rstrip { transition: transform 0.6s var(--roll); }

/* nav */
.nav { position: sticky; top: env(safe-area-inset-top, 0px); z-index: 20; background: rgba(10,10,10,0.75); backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px); }
.nav-in { display: flex; align-items: center; justify-content: space-between; gap: 20px; height: 64px; }
.brand { display: flex; align-items: center; gap: 9px; font: 600 19px/1 var(--word); letter-spacing: -0.01em; }
.brand svg { width: 21px; height: 21px; }
.brand-sm { font-size: 16px; }
.brand-sm svg { width: 17px; height: 17px; }
.links { display: flex; gap: 28px; font-size: 14px; color: var(--fg-2); }
.links a { transition: color 0.15s; }
.links a:hover { color: var(--fg); }
.nav-r { display: flex; gap: 8px; }
.pill { display: inline-flex; align-items: center; justify-content: center; height: 36px; padding: 0 16px; border-radius: 999px; font: 500 14px/1 var(--sans); white-space: nowrap; transition: background 0.15s, transform 0.12s; border: 0; cursor: pointer; }
.pill:active { transform: scale(0.97); }
.pill-w { background: var(--fg); color: #0A0A0A; }
.pill-w:hover { background: #FFFFFF; }
.pill-g { background: #1E1E1E; color: var(--fg); }
.pill-g:hover { background: #2A2A2A; }
.pill-lg { height: 44px; padding: 0 22px; font-size: 15px; }

/* hero */
.hero { padding-block: 96px 0; text-align: center; }
.badge { display: inline-flex; align-items: center; gap: 8px; height: 30px; padding: 0 14px; border-radius: 999px; border: 1px solid var(--line-2); font-size: 13px; color: var(--fg-2); }
.badge b { font: 500 11px/1 var(--mono); letter-spacing: 0.08em; color: var(--fg); }
h1 { margin: 28px auto 0; max-width: 16ch; font: 450 clamp(44px, 6.2vw, 84px)/1.0 var(--sans); letter-spacing: -0.035em; text-wrap: balance; }
.sub { margin: 24px auto 0; max-width: 58ch; color: var(--fg-2); font-size: 18px; text-wrap: balance; }
.ctas { display: flex; justify-content: center; flex-wrap: wrap; gap: 10px; margin-top: 30px; }

/* the diagram */
.diagram { margin-top: 64px; border-radius: 24px; border: 1px solid var(--line); background: radial-gradient(55% 60% at 50% 42%, rgba(255,255,255,0.045), transparent 70%), var(--panel); overflow: hidden; }
.diagram-top { display: flex; justify-content: space-between; align-items: center; gap: 16px; padding: 14px 20px; border-bottom: 1px solid var(--line); font: 400 12px/1 var(--mono); color: var(--fg-3); }
.diagram-top b { color: var(--fg); font-weight: 500; }
.diagram-top .roll { --lh: 1.4em; }
.dt-r { display: flex; align-items: center; gap: 22px; }
.live { display: inline-flex; align-items: center; gap: 8px; }
.live i { width: 6px; height: 6px; border-radius: 99px; background: var(--fg); animation: blink 1.4s ease-in-out infinite; }
@keyframes blink { 50% { opacity: 0.2; } }
.scroll { overflow-x: auto; }
.scroll svg { display: block; width: 100%; height: auto; }
#dia { min-width: 880px; }
.legend { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px 26px; padding: 14px 20px 18px; border-top: 1px solid var(--line); font-size: 13px; color: var(--fg-3); }
.legend span { display: inline-flex; align-items: center; gap: 8px; }
.legend b { color: var(--fg-2); font-weight: 500; }
.key { display: inline-block; width: 22px; height: 12px; border-radius: 6px; }
.key-w { background: #1C1C1C; border: 1px solid #3A3A3A; }
.key-r { background: var(--fg); }

/* svg text */
.n-name { font: 500 14px var(--sans); fill: var(--fg); }
.n-sub { font: 400 11px var(--mono); fill: var(--fg-3); }
.b-head { font: 500 11px var(--mono); fill: var(--fg-3); letter-spacing: 0.06em; }
.b-tag { font: 500 10px var(--mono); fill: var(--fg-2); letter-spacing: 0.06em; }
.b-count { font: 450 30px var(--sans); fill: var(--fg); letter-spacing: -0.02em; font-variant-numeric: tabular-nums; }
.b-last { font: 400 12px var(--mono); fill: var(--fg-2); }
.h-label { font: 600 15px var(--word); fill: var(--fg); }
.h-sub { font: 400 11px var(--mono); fill: var(--fg-3); }
.chip-t { font: 400 11px var(--mono); fill: var(--fg); }
.flow { stroke-dasharray: 2 9; animation: flow 1.2s linear infinite; }
@keyframes flow { to { stroke-dashoffset: -11; } }
.orbit { transform-origin: 600px 236px; animation: spin 40s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

/* small visuals */
.vz-t { font: 400 10px var(--mono); fill: var(--fg-3); }
.vz-l { font: 400 12px var(--mono); fill: var(--fg-3); }
.vz-w { fill: var(--fg); }
.vz-w2 { fill: var(--fg-2); }
.vz-n { font: 500 12px var(--sans); fill: var(--fg); }
.vz-v { font: 450 17px var(--sans); fill: var(--fg); letter-spacing: -0.01em; }
.vz-name { font: 500 14px var(--sans); fill: var(--fg); }
.mv { transition: transform 0.8s var(--move), opacity 0.3s ease; }
.fl { transition: fill 0.5s ease, stroke 0.5s ease; }
.fade { transition: opacity 0.4s ease; }
.sx { transform-box: fill-box; transform-origin: 0 50%; transition: transform 0.5s var(--move); }
.dr { stroke-dasharray: var(--L); stroke-dashoffset: var(--L); }
.on .dr { stroke-dashoffset: 0; transition: stroke-dashoffset 1.8s var(--move); }
.on .dr2 { transition-delay: 0.9s; }
.lbl { opacity: 0; }
.on .lbl { opacity: 1; transition: opacity 0.5s ease 1.5s; }
.brt { animation: breathe 5s ease-in-out infinite alternate; }
@keyframes breathe { from { transform: translateY(calc(var(--dy) * -1)); } to { transform: translateY(var(--dy)); } }
.iso:not(.vis) .brt { animation-play-state: paused; }
.dp-h { display: flex; justify-content: space-between; gap: 12px; font: 400 11px/1 var(--mono); color: var(--fg-3); letter-spacing: 0.06em; }

/* sections */
.sec { padding-block: 128px 0; }
.eyebrow { font-size: 14px; color: var(--fg-2); }
h2 { margin: 12px 0 0; max-width: 20ch; font: 450 clamp(34px, 4.2vw, 54px)/1.06 var(--sans); letter-spacing: -0.025em; text-wrap: balance; }
.lede { margin: 16px 0 0; max-width: 56ch; color: var(--fg-2); font-size: 17px; }
.box { border-radius: 20px; border: 1px solid var(--line); background: var(--card); }

/* how it works */
.steps { margin-top: 44px; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.step { border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); display: flex; flex-direction: column; }
.step .viz { display: block; width: 100%; height: auto; background: var(--panel); border-bottom: 1px solid var(--line); }
.step-b { padding: 20px 24px 28px; display: flex; flex-direction: column; gap: 10px; }
.step .no { font: 400 12px var(--mono); color: var(--fg-3); }
.step h3 { margin: 4px 0 0; font: 450 22px/1.2 var(--sans); letter-spacing: -0.015em; }
.step p { margin: 0; color: var(--fg-2); font-size: 15px; }
.also { margin-top: 14px; display: flex; align-items: center; gap: 14px; padding: 18px 22px; border-radius: 16px; background: var(--panel); border: 1px solid var(--line); color: var(--fg-2); font-size: 15px; }
.also b { color: var(--fg); font-weight: 500; }
.also .mono { font-size: 11px; letter-spacing: 0.08em; color: var(--fg-3); flex-shrink: 0; }

/* drift */
.drift { margin-top: 44px; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.dp { border-radius: 20px; border: 1px solid var(--line); background: var(--panel); padding: 18px 20px 8px; }
.dp svg { display: block; width: 100%; height: auto; margin-top: 8px; }
.vs { margin-top: 12px; border-radius: 20px; border: 1px solid var(--line); overflow: hidden; }
.vs-row { display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 1fr) minmax(0, 1fr); border-top: 1px solid var(--line); }
.vs-row:first-child { border-top: 0; }
.vs-row > div { padding: 20px 22px; min-width: 0; }
.vs-row > div + div { border-left: 1px solid var(--line); }
.vs-h > div { padding-block: 14px; font-size: 13px; color: var(--fg-3); background: var(--panel); }
.vs-h > div:last-child { color: var(--fg); }
.q { font-size: 15px; color: var(--fg); }
.without { color: var(--fg-3); font-size: 15px; }
.with { color: var(--fg); font-size: 15px; }

/* spec sheet */
.spec-wrap { margin-top: 44px; display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 12px; align-items: stretch; }
.iso-box { padding: 18px 20px 10px; background: var(--panel); }
.iso { display: block; width: 100%; height: auto; margin-top: 6px; }
.spec { margin: 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); grid-auto-rows: 1fr; border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.spec div { padding: 22px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); display: flex; flex-direction: column; gap: 10px; }
.spec dt { font: 400 12px var(--mono); color: var(--fg-3); }
.spec dd { margin: 0; font: 450 20px/1.25 var(--sans); letter-spacing: -0.015em; color: var(--fg); }

/* status */
.status { margin-top: 44px; border-radius: 20px; border: 1px solid var(--line); background: var(--panel); overflow: hidden; }
.st-top { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 18px 22px; border-bottom: 1px solid var(--line); }
.st-top b { font-weight: 500; }
.st-top span { font-size: 13px; color: var(--fg-3); text-align: right; }
.st-row { padding: 18px 22px; border-bottom: 1px solid var(--line); display: grid; grid-template-columns: minmax(0, 240px) minmax(0, 1fr) minmax(0, 190px); gap: 22px; align-items: center; }
.st-row:last-child { border-bottom: 0; }
.st-name { font-size: 15px; }
.st-note { font-size: 13px; color: var(--fg-3); text-align: right; }
.bars { display: flex; gap: 2px; height: 28px; min-width: 0; }
.bars i { flex: 1; border-radius: 2px; background: #E5E5E5; }
.bars i.dim { background: #3A3A3A; }
.bars i.mid { background: #8A8A8A; }

/* the calculator: everything you set and everything you pay on one screen */
.calc { margin-top: 40px; display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr); gap: 12px; align-items: stretch; }
.inputs { padding: 22px 24px; display: flex; flex-direction: column; gap: 16px; }
.w-top { display: flex; justify-content: space-between; align-items: center; gap: 10px 16px; flex-wrap: wrap; }
.f-label, .mf label, .tg-top span { font-size: 13px; color: var(--fg-2); }
.f-hint { font-size: 12px; color: var(--fg-3); line-height: 1.45; }
.f-hint b { color: var(--fg-2); font-weight: 400; }
.big { display: block; width: 100%; margin: -4px 0 0; padding: 0; border: 0; background: none; color: var(--fg); font: 450 44px/1.1 var(--sans); letter-spacing: -0.03em; font-variant-numeric: tabular-nums; outline: none; }
.range { -webkit-appearance: none; appearance: none; display: block; width: 100%; height: 22px; margin: 0; background: transparent; cursor: pointer; }
.range::-webkit-slider-runnable-track { height: 4px; border-radius: 4px; background: linear-gradient(to right, #FAFAFA var(--p, 0%), #2A2A2A var(--p, 0%)); }
.range::-moz-range-track { height: 4px; border-radius: 4px; background: #2A2A2A; }
.range::-moz-range-progress { height: 4px; border-radius: 4px; background: #FAFAFA; }
.range::-webkit-slider-thumb { -webkit-appearance: none; width: 20px; height: 20px; margin-top: -8px; border-radius: 99px; background: #FAFAFA; border: 4px solid #151515; box-shadow: 0 0 0 1px #FAFAFA; }
.range::-moz-range-thumb { width: 12px; height: 12px; border-radius: 99px; background: #FAFAFA; border: 4px solid #151515; box-shadow: 0 0 0 1px #FAFAFA; }
.ticks { position: relative; height: 18px; margin: 4px 10px 0; font: 400 11px/18px var(--mono); color: var(--fg-3); }
.ticks span { position: absolute; top: 0; padding-left: 6px; border-left: 1px solid #333; white-space: nowrap; overflow: hidden; transition: color 0.2s; }
.ticks span.on { color: var(--fg); border-left-color: #8A8A8A; }
.presets { display: flex; flex-wrap: wrap; gap: 6px; }
.preset { height: 28px; padding: 0 11px; border-radius: 99px; border: 1px solid var(--line-2); background: none; color: var(--fg-2); font-size: 12px; cursor: pointer; transition: background 0.15s, color 0.15s, border-color 0.15s; }
@media (hover: hover) { .preset:hover { color: var(--fg); border-color: #3A3A3A; } }
.preset[aria-pressed="true"] { background: var(--fg); color: #0A0A0A; border-color: var(--fg); }
.mini3, .mini2 { display: grid; gap: 14px; padding-top: 16px; border-top: 1px solid var(--line); }
.mini3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.mini2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.mf, .tg { display: flex; flex-direction: column; gap: 6px; min-width: 0; }
.num-w { position: relative; display: block; }
.num { width: 100%; height: 38px; padding: 0 12px; border-radius: 10px; border: 1px solid var(--line-2); background: #0F0F0F; color: var(--fg); font: 400 16px var(--sans); font-variant-numeric: tabular-nums; outline: none; transition: border-color 0.15s; }
.num:focus { border-color: #5A5A5A; }
.num-w .num { padding-right: 38px; }
.num-w .u { position: absolute; right: 12px; top: 0; line-height: 38px; font-size: 13px; color: var(--fg-3); pointer-events: none; }
.tg-top { display: flex; justify-content: space-between; align-items: center; gap: 10px; min-height: 26px; }
.sw { position: relative; flex-shrink: 0; width: 44px; height: 26px; border-radius: 99px; border: 0; background: #2A2A2A; cursor: pointer; transition: background 0.18s; }
.sw::after { content: ""; position: absolute; top: 3px; left: 3px; width: 20px; height: 20px; border-radius: 99px; background: #8A8A8A; transition: transform 0.18s cubic-bezier(0.2, 0, 0, 1), background 0.18s; }
.sw[aria-checked="true"] { background: var(--fg); }
.sw[aria-checked="true"]::after { transform: translateX(18px); background: #0A0A0A; }
.commit { display: flex; align-items: center; gap: 8px; font-size: 12px; color: var(--fg-3); }
.commit .num-w { width: 108px; }
.commit .num { height: 32px; padding-left: 22px; padding-right: 10px; }
.commit .cur { position: absolute; left: 10px; top: 0; line-height: 32px; font-size: 13px; color: var(--fg-3); pointer-events: none; }
.warn { color: var(--fg); }

.bill { padding: 20px 22px; display: flex; flex-direction: column; }
.bill-top { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; padding-bottom: 12px; border-bottom: 1px solid var(--line); }
.bill-top b { font-weight: 500; font-size: 15px; }
.bill-top span { font: 400 11px var(--mono); color: var(--fg-3); }
.ln { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 2px 16px; padding: 10px 0; border-bottom: 1px solid var(--line); font-variant-numeric: tabular-nums; }
.ln .k, .ln .v { font-size: 15px; }
.ln .v { text-align: right; }
.ln .roll { --lh: 1.55em; }
.ln .d { grid-column: 1 / -1; font-size: 12px; color: var(--fg-3); }
.ln.off .k, .ln.off .v { color: var(--fg-3); }
.bands { grid-column: 1 / -1; margin-top: 4px; display: grid; gap: 2px; }
.band { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 16px; font: 400 11px/1.5 var(--mono); color: var(--fg-3); }
.band .roll { --lh: 1.5em; }
.band.on { color: var(--fg-2); }
.band span:last-child { text-align: right; }
.total { margin-top: auto; padding-top: 14px; display: flex; justify-content: space-between; align-items: flex-end; gap: 16px; }
.total .k { font-size: 15px; color: var(--fg-2); padding-bottom: 6px; }
.total .v { font: 450 50px/1 var(--sans); letter-spacing: -0.04em; }
.total .roll { --lh: 1.08em; }
.unit { margin-top: 10px; font-size: 12px; color: var(--fg-2); line-height: 1.45; }
.free { margin-top: 12px; padding-top: 12px; border-top: 1px solid var(--line); font-size: 12px; color: var(--fg-3); line-height: 1.45; }

/* end */
.end { padding-block: 150px 120px; text-align: center; }
.end h2 { margin-inline: auto; max-width: 17ch; font-size: clamp(40px, 5.6vw, 72px); }
.mem { margin: 44px auto 0; max-width: 1040px; text-align: left; padding: 18px 20px 10px; background: var(--panel); }
.mem svg { min-width: 680px; margin-top: 8px; }
.mk { display: inline-block; width: 14px; height: 2px; margin: 0 6px 3px 14px; vertical-align: middle; }
.mk-a { background: #6B6B6B; }
.mk-s { background: var(--fg); }
.foot { border-top: 1px solid var(--line); padding-block: 32px 44px; }
.foot-in { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 20px; font-size: 13px; color: var(--fg-3); }
.foot-links { display: flex; gap: 22px; flex-wrap: wrap; }
.foot-links a { transition: color 0.15s; }
@media (hover: hover) { .foot-links a:hover { color: var(--fg); } }

@media (max-width: 1100px) {
  .steps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .spec-wrap { grid-template-columns: minmax(0, 1fr); }
}
@media (max-width: 960px) {
  .links { display: none; }
  .st-row { grid-template-columns: minmax(0, 1fr); gap: 10px; }
  .st-note { text-align: left; }
  .calc { grid-template-columns: minmax(0, 1fr); }
  .drift { grid-template-columns: minmax(0, 1fr); }
}
@media (max-width: 640px) {
  .nav-r .pill-g { display: none; }
  .dt-r > span:first-child { display: none; }
  .steps { grid-template-columns: minmax(0, 1fr); }
  .vs-row { grid-template-columns: minmax(0, 1fr); }
  .vs-row > div + div { border-left: 0; border-top: 1px solid var(--line); }
  .vs-h { display: none; }
  .without::before { content: "Without: "; color: var(--fg-3); }
  .with::before { content: "With: "; color: var(--fg-3); }
  .spec { grid-template-columns: minmax(0, 1fr); grid-auto-rows: auto; }
  .inputs { padding: 18px; }
  .bill { padding: 18px; }
  .big { font-size: 38px; }
  .total .v { font-size: 42px; }
  .mini3, .mini2 { grid-template-columns: minmax(0, 1fr); }
  .also { flex-direction: column; align-items: flex-start; gap: 6px; }
}
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation: none !important; transition: none !important; } }