/* Incrementality Calculator: explorable explanation. Warm white page, violet = test group / what the ads caused,
   tomato = control group / what would have happened anyway. Fraunces, Figtree, Martian Mono. Light mode only. */
:root {
  --bg: #fbf7f0;
  --panel: #f3ece0;
  --ink: #1d1a2b;
  --muted: #625b70;
  --rule: #e2d8c7;
  --violet: #4c2a8f;
  --violet-2: #7d5cc4;
  --violet-t: #e7dff5;
  --tomato: #d9472f;
  --tomato-t: #f5c9bf;
  --sand: #d8cbb3;
  --serif: "Fraunces", Georgia, serif;
  --sans: "Figtree", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "Martian Mono", ui-monospace, Menlo, monospace;
  --read: 700px;
  --wide: 1040px;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 17px/1.62 var(--sans); overflow-x: hidden; }
a { color: var(--violet); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: var(--tomato); }
h1, h2, h3 { font-family: var(--serif); font-weight: 600; line-height: 1.15; letter-spacing: -0.01em; font-variation-settings: "opsz" 72; }
h1 { font-size: clamp(34px, 6vw, 56px); margin: 0 0 14px; font-weight: 500; }
h1 em { font-style: italic; color: var(--violet); }
h2 { font-size: clamp(25px, 3.6vw, 34px); margin: 0 0 14px; }
h3 { font-size: 21px; margin: 26px 0 8px; }
p { margin: 0 0 14px; }
code, .num, .mono { font-family: var(--mono); font-size: 0.82em; }
.wrap { max-width: var(--wide); margin: 0 auto; padding: 0 20px; }
.read { max-width: var(--read); margin: 0 auto; padding: 0 20px; }

/* header */
header.top { border-bottom: 1px solid var(--rule); background: var(--bg); }
header.top .wrap { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 60px; flex-wrap: wrap; }
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); font-family: var(--serif); font-size: 19px; font-weight: 600; }
.brand:hover { color: var(--ink); }
.brand svg { flex: none; }
nav.main { display: flex; gap: 20px; font-size: 15px; }
nav.main a { color: var(--ink); text-decoration: none; padding: 4px 0; border-bottom: 2px solid transparent; }
nav.main a[aria-current] { border-color: var(--tomato); }
nav.main a:hover { color: var(--violet); }

/* hero */
.hero { padding: 54px 0 24px; }
.crumb { font: 12px/1.4 var(--mono); color: var(--muted); margin-bottom: 18px; }
.crumb a { color: var(--muted); }
.lede { font-size: 20px; color: var(--muted); max-width: 640px; }
.answer { margin: 26px 0 6px; padding: 18px 20px 6px; border-left: 4px solid var(--violet); background: #fff; }
.answer .lbl, .kicker { display: block; font: 600 11px/1 var(--mono); letter-spacing: 0.08em; text-transform: uppercase; color: var(--violet); margin-bottom: 10px; }

/* sections: numbered steps down a single reading line */
.step { padding: 40px 0 18px; border-top: 1px solid var(--rule); }
.step .kicker { color: var(--tomato); }
.step:first-of-type { border-top: 0; }
.prose ul, .prose ol, .read ul, .read ol { padding-left: 22px; margin: 0 0 16px; }
.prose li, .read li { margin-bottom: 6px; }
.prose h2 { margin-top: 38px; }
.prose table, table.t { border-collapse: collapse; width: 100%; font-size: 15px; margin: 8px 0 18px; }
.tw { overflow-x: auto; -webkit-overflow-scrolling: touch; margin: 0 0 18px; }
table.t th, table.t td, .prose th, .prose td { text-align: left; padding: 8px 10px; border-bottom: 1px solid var(--rule); vertical-align: top; }
table.t th, .prose th { font: 600 11px/1.3 var(--mono); text-transform: uppercase; letter-spacing: 0.05em; color: var(--muted); border-bottom: 1.5px solid var(--ink); }
table.t td.n { font-family: var(--mono); font-size: 13px; white-space: nowrap; }
.callout { border-left: 3px solid var(--tomato); padding: 2px 0 2px 16px; margin: 18px 0; }
.formula { font-family: var(--mono); font-size: 13.5px; line-height: 1.7; background: #fff; border: 1px solid var(--rule); padding: 12px 14px; margin: 10px 0 16px; overflow-wrap: anywhere; }
.formula b { color: var(--violet); font-weight: 600; }

/* sample-data label: hatched edge so it reads as "not real" */
.sample { display: flex; gap: 10px; align-items: flex-start; font: 12px/1.5 var(--mono); color: var(--muted); margin: 0 0 14px; padding: 6px 10px 6px 0; }
.sample::before { content: ""; flex: none; width: 14px; height: 18px; background: repeating-linear-gradient(135deg, var(--tomato) 0 2px, transparent 2px 5px); }

/* labs */
.lab { background: var(--panel); border-top: 2px solid var(--ink); border-bottom: 1px solid var(--rule); margin: 18px 0 26px; }
.lab-head { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; flex-wrap: wrap; padding: 12px 20px; border-bottom: 1px solid var(--rule); }
.lab-head b { font: 600 12px/1.3 var(--mono); text-transform: uppercase; letter-spacing: 0.06em; }
.lab-head span { font: 12px/1.3 var(--mono); color: var(--muted); }
.lab-body { display: grid; grid-template-columns: minmax(0, 300px) minmax(0, 1fr); gap: 0; }
.lab-body > * { min-width: 0; }
.controls { padding: 18px 20px; border-right: 1px solid var(--rule); }
.stage { padding: 18px 20px; }
.ctl { margin-bottom: 16px; }
.ctl label { display: flex; justify-content: space-between; gap: 8px; font-size: 14px; font-weight: 600; margin-bottom: 4px; }
.ctl label output, .ctl label .v { font: 500 13px/1.4 var(--mono); color: var(--violet); }
.ctl small { display: block; color: var(--muted); font-size: 13px; line-height: 1.4; margin-top: 2px; }
input[type=range] { width: 100%; -webkit-appearance: none; appearance: none; background: transparent; height: 26px; margin: 0; }
input[type=range]::-webkit-slider-runnable-track { height: 3px; background: var(--ink); }
input[type=range]::-moz-range-track { height: 3px; background: var(--ink); }
input[type=range]::-webkit-slider-thumb { -webkit-appearance: none; width: 20px; height: 20px; border-radius: 50%; background: var(--violet); border: 3px solid var(--bg); margin-top: -9px; box-shadow: 0 0 0 1px var(--violet); }
input[type=range]::-moz-range-thumb { width: 16px; height: 16px; border-radius: 50%; background: var(--violet); border: 3px solid var(--bg); }
input[type=range].ctrl::-webkit-slider-thumb { background: var(--tomato); box-shadow: 0 0 0 1px var(--tomato); }
input[type=number] { width: 100%; font: 15px var(--mono); padding: 8px 10px; border: 1px solid var(--sand); background: #fff; color: var(--ink); border-radius: 0; }
input[type=number]:focus, input[type=range]:focus-visible, button:focus-visible { outline: 2px solid var(--violet); outline-offset: 2px; }
.pair { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.grp { font: 600 11px/1.3 var(--mono); text-transform: uppercase; letter-spacing: 0.06em; margin: 4px 0 10px; display: flex; align-items: center; gap: 8px; }
.grp i { width: 10px; height: 10px; display: inline-block; }
.grp.t i, .key .t { background: var(--violet); }
.grp.c i, .key .c { background: var(--tomato); }
.btns { display: flex; gap: 10px; flex-wrap: wrap; }
button { font: 600 13px/1 var(--sans); padding: 10px 14px; border: 1.5px solid var(--ink); background: #fff; color: var(--ink); cursor: pointer; border-radius: 0; }
button:hover { background: var(--ink); color: #fff; }
.readout { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); border-top: 1px solid var(--rule); border-left: 1px solid var(--rule); margin: 14px 0; }
.readout div { padding: 10px 12px; border-right: 1px solid var(--rule); border-bottom: 1px solid var(--rule); background: var(--bg); }
.readout dt { font-size: 12px; color: var(--muted); line-height: 1.3; }
.readout dd { margin: 4px 0 0; font: 500 17px/1.3 var(--mono); }
.readout .t dd { color: var(--violet); }
.readout .c dd { color: var(--tomato); }
.verdict { background: #fff; border-left: 4px solid var(--violet); padding: 12px 14px; font-size: 15.5px; margin: 0; }
.key { display: flex; flex-wrap: wrap; gap: 6px 16px; font-size: 13px; color: var(--muted); margin: 6px 0 10px; }
.key span { display: inline-flex; align-items: center; gap: 6px; }
.key i { width: 12px; height: 12px; display: inline-block; }
.key .o { background: var(--tomato-t); }
.key .line { height: 0; border-top: 2px dashed var(--ink); width: 16px; }
.key .band { background: var(--violet-t); }
.chart svg, .ex-grid svg { width: 100%; height: auto; display: block; }
.ex-grid { max-width: 560px; margin: 8px 0; }
.lab noscript p, .static-note { font-size: 13px; color: var(--muted); }
.lab .static { padding: 0 20px 14px; }
.lab.live .static { display: none; }

/* svg marks */
svg .ax { font: 10.5px var(--mono); fill: var(--muted); }
svg .grid { stroke: var(--rule); stroke-width: 1; }
svg .zero { stroke: var(--ink); stroke-width: 1.2; }
svg .band { fill: var(--violet-t); }
svg .est { fill: none; stroke: var(--violet); stroke-width: 2; }
svg .pt { fill: var(--bg); stroke: var(--violet); stroke-width: 1.5; }
svg .pt.sig { fill: var(--violet); }
svg .ring { fill: none; stroke: var(--tomato); stroke-width: 2; }
svg .truth { stroke: var(--ink); stroke-dasharray: 5 4; stroke-width: 1.3; }
svg .truth-t { fill: var(--ink); }
svg .plan { stroke: var(--tomato); stroke-dasharray: 2 3; stroke-width: 1.5; }
svg .plan-t { fill: var(--tomato); }
svg .ci { fill: var(--sand); }
svg .ci.clear { fill: var(--violet); }
svg .mid { stroke: var(--ink); stroke-width: 2.5; }
svg .push { fill: #fff; }
svg .b-organic, svg .d-organic { fill: var(--tomato-t); }
svg .b-claimed, svg .d-claimed { fill: var(--tomato); }
svg .b-caused, svg .d-caused { fill: var(--violet); }
svg .baseline { fill: none; stroke: var(--ink); stroke-width: 1.2; stroke-dasharray: 4 3; }

/* lists of pages */
.index { list-style: none; padding: 0; margin: 0; border-top: 1px solid var(--rule); }
.index li { border-bottom: 1px solid var(--rule); }
.index a { display: grid; grid-template-columns: 52px 1fr; gap: 4px 14px; padding: 16px 0; text-decoration: none; color: var(--ink); }
.index a:hover b { color: var(--violet); }
.index .no { font: 500 13px/1.6 var(--mono); color: var(--tomato); grid-row: span 2; }
.index b { font-family: var(--serif); font-weight: 600; font-size: 20px; line-height: 1.25; }
.index span:not(.no) { color: var(--muted); font-size: 15px; }

/* glossary */
dl.terms dt { font-family: var(--serif); font-weight: 600; font-size: 19px; margin-top: 20px; }
dl.terms dd { margin: 4px 0 0; }

/* FAQ */
.faq details { border-bottom: 1px solid var(--rule); padding: 12px 0; }
.faq details:first-child { border-top: 1px solid var(--rule); }
.faq summary { cursor: pointer; font-weight: 600; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-family: var(--mono); color: var(--tomato); }
.faq details[open] summary::after { content: "\2212"; }
.faq p { margin: 10px 0 0; color: #36304a; }

/* footer */
footer.site { margin-top: 60px; border-top: 2px solid var(--ink); padding: 34px 0 40px; font-size: 14px; color: var(--muted); }
footer .cols { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 24px; }
footer h4 { font: 600 11px/1.3 var(--mono); text-transform: uppercase; letter-spacing: 0.06em; color: var(--ink); margin: 4px 0 10px; }
footer ul { list-style: none; padding: 0; margin: 0; }
footer li { margin-bottom: 6px; }
footer a { color: var(--muted); }

@media (max-width: 820px) {
  .lab-body { grid-template-columns: 1fr; }
  .controls { border-right: 0; border-bottom: 1px solid var(--rule); }
  footer .cols { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 520px) {
  body { font-size: 16px; }
  .wrap, .read { padding: 0 16px; }
  .controls, .stage, .lab-head { padding-left: 16px; padding-right: 16px; }
  .lab .static { padding: 0 16px 12px; }
  nav.main { gap: 14px; font-size: 14px; }
  .hide-sm { display: none; }
  .hero { padding-top: 36px; }
  .lede { font-size: 18px; }
  .readout { grid-template-columns: 1fr 1fr; }
  footer .cols { grid-template-columns: 1fr; }
  .index a { grid-template-columns: 38px 1fr; }
}
svg .truth-t, svg .plan-t { paint-order: stroke; stroke: var(--panel); stroke-width: 4px; stroke-linejoin: round; }

/* Linkrunner credit (26 Oct 2026): header byline, footer line and link row, quiet "Run this on your own data" panel */
.brandrow { display: flex; align-items: center; gap: 4px 12px; flex-wrap: wrap; }
.by { font: 500 11px/1.3 var(--mono); color: var(--muted); text-decoration: none; letter-spacing: 0.02em; border-bottom: 1px solid var(--sand); padding-bottom: 1px; }
.by:hover { color: var(--violet); border-color: var(--violet); }
footer .made { color: var(--ink); }
footer .made a { color: var(--violet); }
.lr-row { list-style: none; display: flex; flex-wrap: wrap; gap: 6px 22px; margin: 26px 0 0; padding: 16px 0 0; border-top: 1px solid var(--rule); }
.lr-row li { margin: 0; }
.panel-step { border-top: 0; padding-top: 8px; }
.panel { background: #fff; border: 1px solid var(--sand); border-left: 3px solid var(--violet); padding: 14px 18px 6px; }
.panel .lbl { font: 600 11px/1.3 var(--mono); letter-spacing: 0.08em; text-transform: uppercase; color: var(--violet); margin: 0 0 8px; }
.panel p { font-size: 15.5px; }
.read .panel ul { list-style: none; padding: 0; margin: 0 0 10px; display: flex; flex-wrap: wrap; gap: 4px 20px; font-size: 15px; }
.read .panel li { margin: 0; }

/* Three users, one week (#three-users). Tomato tint = organic shown as organic, tomato = organic credited to an ad,
   violet = caused by the ad, same as the explorable's dots. */
.tu { background: var(--panel); border-top: 2px solid var(--ink); border-bottom: 1px solid var(--rule); margin: 18px 0 26px; }
.tu-body { padding: 16px 20px 18px; }
.tu-toggle { display: inline-flex; border: 1.5px solid var(--ink); margin: 0 0 14px; }
.tu-toggle button { border: 0; background: #fff; padding: 10px 16px; }
.tu-toggle button + button { border-left: 1.5px solid var(--ink); }
.tu-toggle button[aria-pressed="true"] { background: var(--ink); color: #fff; }
.tu-days { list-style: none; margin: 0 0 4px 172px; padding: 0; display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 8px; font: 600 11px/1.3 var(--mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--muted); }
.tu-row { display: grid; grid-template-columns: 150px minmax(0, 1fr); gap: 4px 8px; padding: 12px 0 12px 10px; border-top: 1px solid var(--rule); border-left: 4px solid var(--tomato-t); }
.tu-row.u-c { border-left-color: var(--tomato); }
.tu-row.u-t { border-left-color: var(--violet); }
.who b { display: block; font: 600 22px/1.1 var(--serif); }
.who span { display: block; font: 600 11px/1.35 var(--mono); letter-spacing: 0.04em; text-transform: uppercase; color: var(--muted); margin-top: 4px; }
.u-c .who span { color: var(--tomato); }
.u-t .who span { color: var(--violet); }
.track { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: 8px; }
.track .day { margin: 0; min-height: 40px; border-left: 1px dashed var(--sand); padding-left: 6px; }
.track .dl { display: none; }
.ev { background: #fff; border: 1.5px solid var(--rule); padding: 6px 8px; margin: 0 0 6px; font-size: 13px; line-height: 1.35;
      transition: background-color .45s ease, color .45s ease, border-color .45s ease, opacity .45s ease, transform .45s ease; }
.ev b { display: block; font: 600 10px/1.3 var(--mono); letter-spacing: 0.05em; text-transform: uppercase; color: var(--muted); margin-bottom: 2px; }
.u-c .ev.ad { border-color: var(--tomato); }
.u-t .ev.ad { border-color: var(--violet); }
.u-o .ev.inst { background: var(--tomato-t); border-color: var(--tomato-t); }
.u-c .ev.inst { background: var(--tomato); border-color: var(--tomato); color: #fff; }
.u-t .ev.inst { background: var(--violet); border-color: var(--violet); color: #fff; }
.u-c .ev.inst b, .u-t .ev.inst b { color: rgba(255, 255, 255, .85); }
.tu-row .rec { grid-column: 2; margin: 2px 0 0; font-size: 14px; }
.tu-row .ghost { grid-column: 2; margin: 4px 0 0; font-size: 13px; color: var(--muted); border: 1px dashed var(--sand); padding: 4px 8px; }
.tu .wo { display: none; }
.tu[data-state="without"] .w { display: none; }
.tu[data-state="without"] .wo { display: inline; }
.tu[data-state="without"] .ev.ad { border-style: dashed; background: transparent; opacity: .8; }
.tu[data-state="without"] .u-c .ev.inst { background: var(--tomato-t); border-color: var(--tomato-t); color: var(--ink); }
.tu[data-state="without"] .u-c .ev.inst b { color: var(--muted); }
.tu[data-state="without"] .u-t .ev.inst { background: transparent; border: 1.5px dashed var(--violet); color: var(--muted); opacity: .6; transform: scale(.94); }
.tu[data-state="without"] .u-t .ev.inst b { color: var(--violet); }
.tu-tally { margin: 12px 0 0; padding: 10px 14px; background: #fff; border-left: 4px solid var(--violet); font-size: 15px; }
.story-t .r-c th { color: var(--tomato); }
.story-t .r-t th { color: var(--violet); }
.story-t tr.tot th, .story-t tr.tot td { font-weight: 700; border-bottom: 1.5px solid var(--ink); }
table.t.story-t tbody th { font: 15px/1.4 var(--sans); text-transform: none; letter-spacing: 0; border-bottom: 1px solid var(--rule); }
@media (max-width: 760px) {
  .tu-days { display: none; }
  .tu-row { grid-template-columns: 1fr; padding-left: 12px; }
  .track { grid-template-columns: 1fr; gap: 4px; margin-top: 6px; }
  .track .day { border-left: 0; padding-left: 0; min-height: 0; display: grid; grid-template-columns: 50px minmax(0, 1fr); gap: 0 8px; }
  .track .day.empty { display: none; }
  .track .dl { display: block; font: 600 11px/2 var(--mono); text-transform: uppercase; color: var(--muted); grid-row: span 3; }
  .track .ev { grid-column: 2; }
  .tu-row .rec, .tu-row .ghost { grid-column: 1; }
  .tu-body { padding: 14px 16px 16px; }
}
@media (max-width: 520px) {
  .brand { font-size: 17px; }
  .tu-toggle { display: flex; }
  .tu-toggle button { flex: 1; padding: 10px 8px; }
}