*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 12px); }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: var(--lh-body);
  font-feature-settings: 'kern', 'liga';
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}
img, svg, canvas, video { display: block; max-width: 100%; }
button { font: inherit; color: inherit; }
a { color: var(--nv-800); text-decoration: none; background-image: linear-gradient(currentColor, currentColor); background-size: 0% 1px; background-position: 0 100%; background-repeat: no-repeat; transition: background-size 0.3s var(--ease); }
a:hover { background-size: 100% 1px; }
::selection { background: var(--nv-150); color: var(--ink); }
:focus-visible { outline: 2px solid var(--nv-700); outline-offset: 2px; border-radius: 3px; }
.wrap { width: min(var(--w-text), 100% - 2 * var(--gutter)); margin-inline: auto; }
.wide { width: min(var(--w-wide), 100% - 2 * var(--gutter)); margin-inline: auto; }
.full { width: min(var(--w-full), 100% - 2 * var(--gutter)); margin-inline: auto; }
.sec { padding: clamp(72px, 10vw, 128px) 0 clamp(40px, 5vw, 64px); position: relative; }
.sec:last-of-type { padding-bottom: clamp(72px, 10vw, 120px); }
.sec + .sec::before {
  content: ''; position: absolute; top: 0; left: 50%; transform: translateX(-50%);
  width: min(var(--w-wide), 100% - 2 * var(--gutter)); height: 1px; background: var(--hair);
}
.sec.sec--flush::before { display: none; }
.stack > * + * { margin-top: 1.1em; }
.grid-2 { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: clamp(20px, 3vw, 36px); }
.grid-3 { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: clamp(18px, 2.5vw, 28px); }
@media (max-width: 900px) { .grid-3 { grid-template-columns: 1fr 1fr; } }
@media (max-width: 720px) { .grid-2, .grid-3 { grid-template-columns: 1fr; } }
h1, h2, h3, h4 { font-family: var(--font-display); font-weight: 500; color: var(--ink); margin: 0; letter-spacing: -0.01em; font-optical-sizing: auto; }
h2 { font-size: clamp(30px, 4.2vw, 46px); line-height: 1.08; }
h3 { font-size: clamp(22px, 2.4vw, 27px); line-height: 1.2; }
h4 { font-family: var(--font-sans); font-size: 15px; font-weight: 600; letter-spacing: 0; }
p { margin: 0; }
p + p { margin-top: 0.9em; }
strong, b { font-weight: 600; }
em { font-style: italic; }
small, .small { font-size: 14px; }
.muted { color: var(--muted); }
.mono { font-family: var(--font-mono); }
.num { font-variant-numeric: tabular-nums; }
.sec-head { margin-bottom: clamp(28px, 4vw, 48px); }
.kicker {
  display: inline-flex; align-items: center; gap: 10px;
  font-family: var(--font-mono); font-size: 12.5px; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--muted); margin-bottom: 14px;
}
.kicker .kicker-num { color: var(--nv-800); font-weight: 500; }
.kicker::after { content: ''; width: 36px; height: 1px; background: var(--hair-2); }
.sec-head h2 + .lede { margin-top: 18px; }
.lede { font-size: clamp(18px, 1.9vw, 20.5px); line-height: 1.55; color: var(--ink-3); max-width: 62ch; }
.para b.lead, .para strong.lead { color: var(--ink); }
.takeaway {
  position: relative; padding: 14px 18px 14px 20px; margin: 22px 0 0;
  background: var(--nv-50); border: 1px solid var(--nv-150); border-left: 3px solid var(--nv-700); border-radius: 0 var(--radius) var(--radius) 0;
  color: var(--ink-2); font-size: 16px; line-height: 1.55;
}
.takeaway .tk { font-family: var(--font-mono); font-size: 11.5px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--nv-800); display: block; margin-bottom: 4px; }
.caveat { font-size: 14px; color: var(--muted); margin-top: 10px; line-height: 1.5; }
.caveat::before { content: 'Note. '; font-weight: 600; color: var(--ink-3); }
.fig { margin: 0; }
.fig figcaption, .figcap { font-size: 14.5px; line-height: 1.5; color: var(--ink-3); margin-top: 12px; }
.figcap b, .fig figcaption b { color: var(--ink); }
.src { font-family: var(--font-mono); font-size: 11.5px; color: var(--muted); letter-spacing: 0.02em; white-space: nowrap; }
.stage .src { color: var(--stage-muted); }
.chip {
  display: inline-flex; align-items: center; gap: 6px; padding: 3px 10px; border-radius: 999px;
  border: 1px solid var(--hair-2); background: var(--card); font-size: 13px; color: var(--ink-3); line-height: 1.5;
}
.chip--green { border-color: var(--nv-200); background: var(--nv-100); color: var(--nv-900); }
.swatch { display: inline-block; width: 14px; height: 3px; border-radius: 2px; vertical-align: middle; }
.btn {
  display: inline-flex; align-items: center; gap: 8px; padding: 9px 18px; border-radius: 999px;
  background: var(--ink); color: #fff; border: 1px solid var(--ink); font-size: 15px; font-weight: 500; line-height: 1.2;
  background-image: none; transition: background-color 0.25s var(--ease), border-color 0.25s var(--ease), transform 0.25s var(--ease);
}
.btn:hover { background: var(--nv-700); border-color: var(--nv-700); color: #fff; transform: translateY(-1px); }
.btn svg { width: 16px; height: 16px; }
.btn .btn-emoji { font-size: 15px; line-height: 1; }
.btn--ghost { background: transparent; color: var(--ink); border-color: var(--hair-2); }
.btn--ghost:hover { background: var(--nv-100); color: var(--nv-900); border-color: var(--nv-200); }
.btn[aria-disabled='true'] { opacity: 0.45; pointer-events: none; }
.seg { display: inline-flex; padding: 3px; gap: 2px; border-radius: 999px; background: var(--paper-2); border: 1px solid var(--hair); }
.seg button {
  border: 0; background: transparent; padding: 5px 13px; border-radius: 999px; font-size: 13.5px; color: var(--ink-3); cursor: pointer;
  transition: background-color 0.2s var(--ease), color 0.2s var(--ease);
}
.seg button:hover { color: var(--ink); }
.seg button[aria-pressed='true'], .seg button[aria-selected='true'] { background: var(--card); color: var(--ink); box-shadow: 0 1px 2px rgba(0,0,0,.08), 0 0 0 1px var(--hair); }
.stage .seg { background: var(--stage-2); border-color: var(--stage-hair); }
.stage .seg button { color: var(--stage-muted); }
.stage .seg button:hover { color: var(--stage-ink); }
.stage .seg button[aria-pressed='true'], .stage .seg button[aria-selected='true'] { background: var(--stage-3); color: var(--stage-ink); box-shadow: 0 0 0 1px var(--stage-hair); }
.range { -webkit-appearance: none; appearance: none; width: 100%; height: 28px; background: transparent; cursor: pointer; }
.range::-webkit-slider-runnable-track { height: 3px; border-radius: 3px; background: var(--hair-2); }
.range::-moz-range-track { height: 3px; border-radius: 3px; background: var(--hair-2); }
.range::-webkit-slider-thumb { -webkit-appearance: none; width: 18px; height: 18px; border-radius: 50%; background: var(--nv-700); margin-top: -7.5px; border: 3px solid var(--paper); box-shadow: 0 0 0 1px var(--nv-700); }
.range::-moz-range-thumb { width: 14px; height: 14px; border-radius: 50%; background: var(--nv-700); border: 3px solid var(--paper); box-shadow: 0 0 0 1px var(--nv-700); }
.stage .range::-webkit-slider-runnable-track { background: var(--stage-hair); }
.stage .range::-moz-range-track { background: var(--stage-hair); }
.stage .range::-webkit-slider-thumb { background: var(--s-orange); border-color: var(--stage); box-shadow: 0 0 0 1px var(--s-orange); }
.stage .range::-moz-range-thumb { background: var(--s-orange); border-color: var(--stage); box-shadow: 0 0 0 1px var(--s-orange); }
.stage {
  position: relative; background: var(--stage); color: var(--stage-ink); border-radius: var(--radius-lg);
  overflow: hidden; isolation: isolate;
  box-shadow: 0 1px 0 rgba(255,255,255,.04) inset, 0 20px 50px -24px rgba(10, 30, 0, 0.45);
}
.stage::before { 
  content: ''; position: absolute; inset: 0; z-index: -1; pointer-events: none;
  background-image:
    linear-gradient(to right, rgba(237,242,234,.035) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(237,242,234,.035) 1px, transparent 1px);
  background-size: 40px 40px; background-position: -1px -1px;
  -webkit-mask-image: radial-gradient(ellipse at 50% 45%, #000 40%, transparent 85%);
  mask-image: radial-gradient(ellipse at 50% 45%, #000 40%, transparent 85%);
}
.stage a { color: var(--s-green-2); }
.stage .stage-cap, .stage figcaption { color: var(--stage-ink-2); font-size: 14.5px; line-height: 1.5; }
.stage .label, .stage-label { font-family: var(--font-math); fill: var(--stage-ink); color: var(--stage-ink); }
.stage .katex { color: inherit; }
.stage-pad { padding: clamp(18px, 3vw, 36px); }
.stage-toolbar { display: flex; flex-wrap: wrap; align-items: center; gap: 10px 16px; }
.stage-tag { font-family: var(--font-mono); font-size: 11.5px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--stage-muted); }
.t-readout { font-family: var(--font-mono); font-size: 13px; color: var(--s-orange); font-variant-numeric: tabular-nums; }
.c-x { color: var(--s-white); }
.c-e { color: var(--s-blue); }
.c-g { color: var(--s-green); }
.c-t { color: var(--s-orange); }
.on-paper .c-e, .wrap .c-e { color: var(--c2); }
.on-paper .c-g, .wrap .c-g { color: var(--nv-800); }
.on-paper .c-t, .wrap .c-t { color: var(--c3); }
.tbl-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }
.tbl { width: 100%; border-collapse: collapse; font-size: 14.5px; font-variant-numeric: tabular-nums; }
.tbl caption { caption-side: bottom; text-align: left; font-size: 14px; color: var(--ink-3); padding-top: 10px; line-height: 1.5; }
.tbl thead th { font-weight: 600; color: var(--ink); text-align: left; border-top: 1.5px solid var(--ink); border-bottom: 1px solid var(--ink); padding: 8px 10px; white-space: nowrap; }
.tbl tbody td { padding: 6px 10px; border-bottom: 1px solid var(--hair); white-space: nowrap; }
.tbl tbody tr:last-child td { border-bottom: 1.5px solid var(--ink); }
.tbl td.r, .tbl th.r { text-align: right; }
.tbl td.c, .tbl th.c { text-align: center; }
.tbl tr.grp td { font-style: italic; color: var(--muted); background: transparent; padding-top: 12px; font-size: 13.5px; }
.tbl tr.latent td { color: var(--muted); }
.tbl tr.ours td { background: var(--nv-100); color: var(--ink); }
.tbl tr.ours td:first-child { box-shadow: inset 3px 0 0 var(--nv-700); }
.tbl .best { font-weight: 700; }
.tbl .second { text-decoration: underline; text-underline-offset: 3px; }
.chart { position: relative; width: 100%; }
.chart svg { width: 100%; height: auto; overflow: visible; }
.chart .ax text, .chart .tick text { font-family: var(--font-sans); font-size: 12px; fill: var(--muted); font-variant-numeric: tabular-nums; }
.chart .ax-label { font-family: var(--font-sans); font-size: 12.5px; fill: var(--ink-3); }
.chart .grid line { stroke: var(--grid); stroke-width: 1; shape-rendering: crispEdges; }
.chart .axis-line { stroke: var(--axis); stroke-width: 1; shape-rendering: crispEdges; }
.chart .dlabel { font-family: var(--font-sans); font-size: 12.5px; fill: var(--ink-2); font-variant-numeric: tabular-nums; }
.chart .dlabel.strong { font-weight: 600; fill: var(--ink); }
.chart .anno { font-family: var(--font-sans); font-size: 12.5px; fill: var(--ink-3); }
.chart .anno-line { stroke: var(--ink-3); stroke-width: 1; fill: none; }
.chart .crosshair { stroke: var(--ink-3); stroke-width: 1; opacity: 0; transition: opacity .15s; pointer-events: none; }
.chart.is-hover .crosshair { opacity: 0.35; }
.chart--dark .ax text, .chart--dark .tick text { fill: var(--stage-muted); }
.chart--dark .ax-label { fill: var(--stage-ink-2); }
.chart--dark .grid line { stroke: var(--d-grid); }
.chart--dark .axis-line { stroke: var(--d-axis); }
.chart--dark .dlabel { fill: var(--stage-ink-2); }
.chart--dark .dlabel.strong { fill: var(--stage-ink); }
.chart--dark .anno { fill: var(--stage-ink-2); }
.chart--dark .anno-line, .chart--dark .crosshair { stroke: var(--stage-ink-2); }
.chart-head { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 8px 16px; margin-bottom: 8px; }
.chart-title { font-family: var(--font-sans); font-size: 15px; font-weight: 600; color: var(--ink); }
.chart--dark .chart-title { color: var(--stage-ink); }
.legend { display: flex; flex-wrap: wrap; gap: 4px 16px; font-size: 13px; color: var(--ink-3); }
.legend .li { display: inline-flex; align-items: center; gap: 7px; cursor: default; transition: opacity .2s; }
.legend .li svg { width: 22px; height: 10px; overflow: visible; }
.chart--dark .legend { color: var(--stage-ink-2); }
.chart .data-toggle { border: 1px solid var(--hair-2); background: var(--card); color: var(--ink-3); font-size: 12px; font-family: var(--font-mono); padding: 3px 9px; border-radius: 6px; cursor: pointer; }
.chart .data-toggle:hover { color: var(--ink); border-color: var(--ink-3); }
.chart--dark .data-toggle { background: var(--stage-2); border-color: var(--stage-hair); color: var(--stage-muted); }
.chart--dark .data-toggle:hover, .chart--dark .data-toggle[aria-pressed='true'] { color: var(--stage-ink); border-color: var(--stage-muted); background: var(--stage-3); }
.chart .chart-table { display: none; margin-top: 6px; }
.chart.show-table .chart-table { display: block; }
.chart.show-table .chart-svg { display: none; }
.chart--dark .tbl thead th { color: var(--stage-ink); border-color: var(--stage-ink-2); }
.chart--dark .tbl tbody td { border-color: var(--stage-hair); color: var(--stage-ink-2); }
.chart--dark .tbl tbody tr:last-child td { border-bottom-color: var(--stage-ink-2); }
.tip {
  position: fixed; z-index: 1000; pointer-events: none; min-width: 120px; max-width: 280px;
  background: rgba(20, 24, 20, 0.94); color: #f2f5ef; border-radius: 8px; padding: 8px 10px; font-size: 12.5px; line-height: 1.45;
  box-shadow: 0 8px 24px rgba(0,0,0,.22); opacity: 0; transform: translateY(4px); transition: opacity .12s, transform .12s;
  backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px);
}
.tip.on { opacity: 1; transform: none; }
.tip .tt { color: #b9c2b4; font-size: 11.5px; margin-bottom: 3px; }
.tip .tr { display: flex; align-items: center; gap: 8px; white-space: nowrap; }
.tip .tr .k { width: 12px; height: 2px; border-radius: 2px; flex: none; }
.tip .tr .v { font-weight: 600; font-variant-numeric: tabular-nums; min-width: 38px; }
.tip .tr .n { color: #c8d0c3; }
.pd2-js [data-reveal] { opacity: 0; transform: translateY(18px); transition: opacity 0.9s var(--ease), transform 0.9s var(--ease); transition-delay: var(--rd, 0ms); }
.pd2-js [data-reveal].is-in { opacity: 1; transform: none; }
.pd2-js [data-reveal='fade'] { transform: none; }
.pd2-js [data-reveal='left'] { transform: translateX(-22px); }
.pd2-js [data-reveal='right'] { transform: translateX(22px); }
.pd2-js [data-reveal='scale'] { transform: scale(0.97); }
.pd2-js [data-reveal].is-in { opacity: 1; transform: none; }
.pd2-static [data-reveal], .pd2-reduced [data-reveal] { opacity: 1 !important; transform: none !important; transition: none !important; }
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 50; height: var(--nav-h);
  display: flex; align-items: center; background: rgba(252, 252, 252, 0.95);
  backdrop-filter: saturate(1.4) blur(12px); -webkit-backdrop-filter: saturate(1.4) blur(12px);
  border-bottom: 1px solid transparent; transform: translateY(-100%); transition: transform .45s var(--ease), border-color .3s;
}
.nav.is-on, .nav:focus-within { transform: none; border-bottom-color: var(--hair); }
.nav .full { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.nav .nav-brand { flex: none; }
.nav-brand { font-family: var(--font-display); font-size: 21px; font-weight: 600; color: var(--ink); background-image: none; letter-spacing: -0.01em; }
.nav-brand span { background: var(--nv-grad); -webkit-background-clip: text; background-clip: text; color: transparent; }
.nav-links { display: flex; gap: 2px; overflow-x: auto; scrollbar-width: none; min-width: 0; flex: 0 1 auto; margin-left: auto;
  -webkit-mask-image: linear-gradient(90deg, transparent 0, #000 10px, #000 calc(100% - 24px), transparent);
  mask-image: linear-gradient(90deg, transparent 0, #000 10px, #000 calc(100% - 24px), transparent); padding: 0 18px 0 8px; }
.nav-links::-webkit-scrollbar { display: none; }
.nav-links a { font-size: 14px; color: var(--ink-3); padding: 6px 11px; border-radius: 999px; background-image: none; white-space: nowrap; transition: background-color .2s, color .2s; }
.nav-links a:hover { color: var(--ink); background: var(--paper-2); }
.nav-links a.is-active { color: var(--nv-900); background: var(--nv-100); }
.nav-progress { position: absolute; left: 0; bottom: -1px; height: 2px; width: 100%; transform-origin: 0 50%; transform: scaleX(0); background: var(--nv-grad); }
@media (max-width: 760px) { .nav-links a { padding: 6px 8px; font-size: 13px; } .nav-brand { font-size: 18px; } }
.nav-pause { flex: none; display: inline-flex; align-items: center; gap: 7px; border: 1px solid var(--hair-2); background: var(--card); color: var(--ink-3); border-radius: 999px; padding: 5px 11px; font-size: 13px; cursor: pointer; min-height: 32px; }
.nav-pause:hover { color: var(--ink); border-color: var(--ink-3); }
.nav-pause .np-ic { width: 10px; height: 10px; display: inline-block; background: linear-gradient(90deg, currentColor 0 35%, transparent 35% 65%, currentColor 65%); }
.nav-pause[aria-pressed='true'] { background: var(--nv-100); border-color: var(--nv-200); color: var(--nv-900); }
.nav-pause[aria-pressed='true'] .np-ic { background: none; width: 0; height: 0; border-left: 9px solid currentColor; border-top: 5.5px solid transparent; border-bottom: 5.5px solid transparent; }
@media (max-width: 760px) { .nav-pause .np-txt { display: none; } .nav-pause { padding: 5px 10px; } }
.skip-link { position: absolute; left: -9999px; top: 8px; z-index: 100; }
.skip-link:focus { left: 12px; padding: 8px 14px; background: var(--card); color: var(--ink); border-radius: 8px; box-shadow: 0 2px 10px rgba(0,0,0,.15); background-image: none; }
main:focus { outline: none; }
@media (pointer: coarse) { .data-toggle, .btn, .seg button { min-height: 32px; } .nav-brand { padding-block: 6px; } .range { height: 36px; } }
.foot { border-top: 1px solid var(--hair); padding: 36px 0 48px; color: var(--muted); font-size: 13.5px; }
.foot .full { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; }
.katex { font-size: 1.06em; }
.katex-display { margin: 0.9em 0; overflow-x: auto; overflow-y: hidden; padding: 4px 0; }
.eq { font-size: 1.05em; }
.sr-only { position: absolute !important; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }
.center { text-align: center; }
.mt-s { margin-top: 12px; } .mt-m { margin-top: 24px; } .mt-l { margin-top: 44px; } .mt-xl { margin-top: 72px; }
.card { background: var(--card); border: 1px solid var(--hair); border-radius: var(--radius-lg); padding: clamp(18px, 2.4vw, 28px); }
.card--flat { background: transparent; border: 0; padding: 0; }
hr.rule { border: 0; height: 1px; background: var(--hair); margin: 40px 0; }
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}
@media print {
  .nav, .data-toggle, .seg { display: none !important; }
  .stage { box-shadow: none; }
  [data-reveal] { opacity: 1 !important; transform: none !important; }
}
@media (max-width: 600px) { .src, .stage-tag { font-size: 12px; } }