:root {
  color-scheme: dark;
  --surface-0: #111110;
  --surface-1: #1a1a19;
  --surface-2: #222220;
  --text-primary: #f0efec;
  --text-secondary: #c3c2b7;
  --text-muted: #8f8e86;
  --grid: #2a2a28;
  --axis: #3d3d3a;
  --series-1: #3987e5;
  --series-2: #d95926;
  --series-3: #199e70;
  --series-4: #c98500;
  --curve-mix: #fff;
  --accent: #3987e5;
  --radius: 14px;
  --column: 720px;
  --wide: 1120px;
}

* { box-sizing: border-box; }
/* Anchors land below the sticky nav (52px and its border), with some room. */
html { background: var(--surface-0); scroll-padding-top: 76px; scroll-behavior: smooth; }
body {
  margin: 0; color: var(--text-primary); background: var(--surface-0);
  font: 16.5px/1.65 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: #7fb2f0; text-underline-offset: 3px; }
a:hover { color: #a9cbf6; }
code { font: 0.9em ui-monospace, "SF Mono", Menlo, monospace; background: var(--surface-2); padding: 1px 6px; border-radius: 6px; }
pre { background: var(--surface-1); border-radius: 10px; padding: 14px 16px; overflow-x: auto; box-shadow: 0 0 0 1px var(--grid) inset; font-size: 13.5px; line-height: 1.55; }
pre code { background: none; padding: 0; }

.page { padding: 0 24px 96px; }
.column { max-width: var(--column); margin: 0 auto; }
.wide { max-width: var(--wide); margin: 0 auto; }

nav.top {
  position: sticky; top: 0; z-index: 5; backdrop-filter: blur(12px);
  background: color-mix(in srgb, var(--surface-0) 82%, transparent);
  border-bottom: 1px solid var(--grid); margin: 0 -24px; padding: 0 24px;
}
nav.top .wide { display: flex; align-items: center; gap: 22px; height: 52px; overflow-x: auto; scrollbar-width: none; }
nav.top a { color: var(--text-secondary); text-decoration: none; font-size: 14px; white-space: nowrap; }
nav.top a:hover { color: var(--text-primary); }
nav.top .brand { color: var(--text-primary); font-weight: 650; margin-right: auto; display: inline-flex; align-items: center; gap: 9px; }
nav.top .brand img { width: 24px; height: 24px; border-radius: 22%; flex: none; }

.hero { padding: 72px 0 28px; }
.kicker { color: var(--text-muted); font-size: 13.5px; letter-spacing: 0.06em; text-transform: uppercase; margin: 0 0 12px; }
h1 { font-size: clamp(34px, 5.4vw, 56px); line-height: 1.06; letter-spacing: -0.025em; margin: 0 0 18px; font-weight: 720; }
.lede { font-size: 19px; color: var(--text-secondary); max-width: 640px; margin: 0; }
h2 { font-size: 28px; letter-spacing: -0.015em; margin: 72px 0 6px; line-height: 1.2; }
h2 .num { color: var(--text-muted); font-weight: 500; margin-right: 10px; }
h3 { font-size: 18px; margin: 32px 0 6px; }
p { margin: 12px 0; }
.dim { color: var(--text-secondary); }
.muted { color: var(--text-muted); font-size: 13.5px; }
.byline { color: var(--text-muted); font-size: 14px; margin-top: 22px; }

.card { position: relative; background: var(--surface-1); border-radius: var(--radius); padding: 20px 22px; box-shadow: 0 0 0 1px var(--grid) inset; }
.card h3 { margin-top: 0; font-size: 16px; }
.figure { margin: 26px auto; }
.figure .caption { color: var(--text-muted); font-size: 13.5px; margin: 10px 2px 0; }
.grid-2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(440px, 1fr)); gap: 14px; }
.grid-4 { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 14px; }
@media (max-width: 520px) { .grid-2 { grid-template-columns: 1fr; } }

/* The converter */
.converter { margin-top: 40px; display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr); gap: 0; padding: 0; overflow: hidden; }
.converter .controls { padding: 24px 26px; }
.converter .answer { padding: 24px 26px; background: var(--surface-2); display: flex; flex-direction: column; justify-content: center; }
@media (max-width: 760px) { .converter { grid-template-columns: 1fr; } }
.label { color: var(--text-secondary); font-size: 13.5px; margin-bottom: 8px; }
.segmented { position: relative; display: inline-grid; grid-auto-flow: column; grid-auto-columns: 1fr; background: var(--surface-0); border-radius: 11px; padding: 4px; box-shadow: 0 0 0 1px var(--grid) inset; }
.segmented button { position: relative; z-index: 1; border: 0; background: none; color: var(--text-secondary); font: inherit; font-size: 14px; padding: 7px 14px; cursor: pointer; border-radius: 8px; display: inline-flex; gap: 7px; align-items: center; justify-content: center; }
.segmented button[aria-pressed='true'] { color: var(--text-primary); }
.segmented button i { width: 8px; height: 8px; border-radius: 50%; }
.segmented .slide { position: absolute; z-index: 0; top: 4px; bottom: 4px; border-radius: 8px; background: var(--surface-2); box-shadow: 0 0 0 1px var(--axis) inset; transition: left 0.35s cubic-bezier(0.22, 1, 0.36, 1), width 0.35s cubic-bezier(0.22, 1, 0.36, 1); }
.rating-row { display: flex; align-items: baseline; gap: 10px; margin-top: 22px; }
.rating-row input[type='number'] {
  width: 120px; font: 650 34px/1 system-ui, sans-serif; color: var(--text-primary); background: none; border: 0;
  border-bottom: 2px solid var(--axis); padding: 2px 0; font-variant-numeric: tabular-nums; letter-spacing: -0.02em;
}
.rating-row input[type='number']:focus { outline: none; border-color: var(--accent); }
input[type='range'] { width: 100%; margin-top: 14px; accent-color: var(--accent); }
.answer .big { font-size: 56px; font-weight: 720; letter-spacing: -0.03em; line-height: 1; font-variant-numeric: tabular-nums; }
.answer .big small { font-size: 22px; color: var(--text-muted); font-weight: 500; margin-right: 6px; }
.answer .range { margin-top: 12px; color: var(--text-secondary); font-size: 14.5px; }
.answer .range b { color: var(--text-primary); font-variant-numeric: tabular-nums; }
.meter { position: relative; height: 10px; border-radius: 5px; background: var(--surface-0); margin-top: 16px; }
.meter .iqr { position: absolute; top: 0; bottom: 0; border-radius: 5px; opacity: 0.45; transition: left 0.3s, width 0.3s; }
.meter .dot { position: absolute; top: 50%; width: 14px; height: 14px; margin: -7px 0 0 -7px; border-radius: 50%; box-shadow: 0 0 0 3px var(--surface-2); transition: left 0.3s; }

.tiles { display: grid; grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); gap: 12px; margin-top: 14px; }
.tile .value { font-size: 28px; font-weight: 680; letter-spacing: -0.02em; font-variant-numeric: tabular-nums; }
.tile .note { color: var(--text-muted); font-size: 13px; }

/* Charts */
.legend { display: flex; gap: 16px; flex-wrap: wrap; margin: 4px 0 8px; font-size: 13px; color: var(--text-secondary); }
.legend span { display: inline-flex; align-items: center; gap: 7px; }
.legend i { width: 16px; height: 3px; border-radius: 2px; display: inline-block; }
.legend i.dot { width: 8px; height: 8px; border-radius: 50%; }
.legend i.ring { width: 9px; height: 9px; border-radius: 50%; background: none !important; box-shadow: 0 0 0 2px var(--text-primary) inset; }
.legend i.band { height: 10px; opacity: 0.3; }
.legend i.dash { background: repeating-linear-gradient(90deg, var(--text-muted) 0 4px, transparent 4px 7px); }
.chart { position: relative; }
.chart svg { display: block; width: 100%; height: auto; overflow: visible; }
.grid-line { stroke: var(--grid); stroke-dasharray: 3 4; }
.axis-line { stroke: var(--axis); }
.tick { fill: var(--text-muted); font-size: 11px; font-variant-numeric: tabular-nums; }
.axis-title { fill: var(--text-secondary); font-size: 11.5px; }
.direct { fill: var(--text-secondary); font-size: 12px; font-variant-numeric: tabular-nums; }
.tooltip {
  position: absolute; pointer-events: none; padding: 8px 11px; border-radius: 10px; font-size: 13px; line-height: 1.45;
  background: color-mix(in srgb, var(--surface-2) 86%, transparent); backdrop-filter: blur(8px);
  box-shadow: 0 0 0 1px var(--axis) inset, 0 8px 24px rgb(0 0 0 / 0.3); white-space: nowrap; opacity: 0; transition: opacity 0.12s;
  font-variant-numeric: tabular-nums; z-index: 3;
}
.tooltip b { font-weight: 650; }
.tooltip .row { display: flex; align-items: center; gap: 7px; }
.tooltip i { width: 8px; height: 8px; border-radius: 50%; display: inline-block; }
.panel-head { display: flex; justify-content: space-between; align-items: baseline; gap: 10px; flex-wrap: wrap; }
.panel-head h3 { margin: 0; }
.badges { display: flex; gap: 6px; flex-wrap: wrap; margin-top: 10px; }
.badge { font-size: 12px; padding: 2px 9px; border-radius: 999px; box-shadow: 0 0 0 1px var(--grid) inset; color: var(--text-secondary); font-variant-numeric: tabular-nums; }

/* Copying a figure as an image */
.card.exportable > h3, .card.exportable > .panel-head { padding-right: 70px; }
.figure-tools { position: absolute; top: 11px; right: 12px; z-index: 2; display: flex; gap: 2px; opacity: 0; transition: opacity 0.15s; }
.card:hover .figure-tools, .figure-tools:focus-within { opacity: 1; }
@media (hover: none) { .figure-tools { opacity: 1; } }
.figure-tools button {
  display: grid; place-items: center; width: 30px; height: 30px; padding: 0; border: 0; border-radius: 8px;
  background: none; color: var(--text-muted); cursor: pointer;
}
.figure-tools button:hover { color: var(--text-primary); background: var(--surface-2); }
.figure-tools button:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }
.figure-tools button.done { color: var(--series-3); }
.figure-tools button.failed { color: var(--series-2); }
.figure-tools svg { fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

/* Tables */
.table-wrap { overflow-x: auto; }
table { border-collapse: collapse; width: 100%; font-variant-numeric: tabular-nums; font-size: 14px; }
th, td { padding: 7px 12px; text-align: right; border-bottom: 1px solid var(--grid); white-space: nowrap; }
th { color: var(--text-secondary); font-weight: 600; font-size: 13px; }
th:first-child, td:first-child { text-align: left; }
td .spread { color: var(--text-muted); font-size: 12.5px; margin-left: 4px; }
th i { width: 8px; height: 8px; border-radius: 50%; display: inline-block; margin-right: 6px; }
tbody tr:hover td { background: var(--surface-2); }

/* The funnel */
.funnel { display: grid; gap: 9px; }
.funnel .step { display: grid; grid-template-columns: minmax(180px, 280px) 1fr; gap: 14px; align-items: center; }
.funnel .name { color: var(--text-secondary); font-size: 14px; line-height: 1.35; }
.funnel .name small { display: block; color: var(--text-muted); font-size: 12.5px; }
.funnel .track { position: relative; height: 26px; }
.funnel .bar { height: 100%; border-radius: 0 4px 4px 0; background: var(--series-1); min-width: 3px; }
.funnel .bar.pairs { background: var(--series-2); }
.funnel .count { position: absolute; top: 3px; font-size: 13.5px; font-variant-numeric: tabular-nums; color: var(--text-primary); }
@media (max-width: 600px) { .funnel .step { grid-template-columns: 1fr; gap: 4px; } }

/* Math and notes */
.math-block { overflow-x: auto; overflow-y: hidden; padding: 4px 0; }
.katex { font-size: 1.08em; }
.katex-display { margin: 18px 0; }
.note-box { border-left: 3px solid var(--axis); padding: 2px 0 2px 16px; color: var(--text-secondary); margin: 18px 0; }
ul, ol { padding-left: 22px; }
li { margin: 6px 0; }
dl.defs { display: grid; grid-template-columns: max-content 1fr; gap: 6px 18px; }
dl.defs dt { font-family: ui-monospace, Menlo, monospace; font-size: 13.5px; color: var(--text-primary); }
dl.defs dd { margin: 0; color: var(--text-secondary); }
footer { margin-top: 96px; padding-top: 24px; border-top: 1px solid var(--grid); color: var(--text-muted); font-size: 14px; }

@media (max-width: 520px) {
  .page { padding: 0 16px 72px; }
  nav.top { margin: 0 -16px; padding: 0 16px; }
  .converter .controls, .converter .answer { padding: 18px; }
  .segmented { display: grid; width: 100%; }
  .segmented button { padding: 7px 4px; font-size: 13px; gap: 5px; }
  .answer .big { font-size: 46px; }
  .card:not(.converter) { padding: 16px; }
}