/* ============================================================================
   VeriPhy project page - design system
   Dark by intent: the clips are the brightest thing on screen and everything
   else recedes. Colour never carries meaning alone; every state is worded.
   ========================================================================= */

:root{
  /* surfaces */
  --page:#0a0b0e;
  --panel:#14161b;
  --panel-2:#1b1e25;
  --line:rgba(148,163,184,.16);
  --line-2:rgba(148,163,184,.30);

  /* ink - all >= 4.5:1 on --page */
  --fg-1:#f0f2f5;
  --fg-2:#a8afbd;
  --fg-3:#737b8a;

  /* One accent. Baseline is neutral, VeriPhy is accented: a neutral-vs-accent
     pair survives every form of colour blindness, which red/green does not. */
  --accent:#22d3a5;
  --accent-soft:rgba(34,211,165,.12);
  --accent-line:rgba(34,211,165,.42);
  --warn:#fab219;
  --serious:#ec835a;

  --ui:Inter,ui-sans-serif,system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;

  --r:12px;
  --gap:20px;
  --maxw:1240px;

  /* First-viewport guarantee. The stage is sized from the height actually left
     over, so the clip switcher is always reachable without scrolling. */
  --chrome:470px;
  --vid-h:clamp(170px,calc(100svh - var(--chrome)),400px);
  --stage-w:calc(var(--vid-h) * 32 / 9 + var(--gap));
}
@media (max-width:900px){ :root{ --chrome:392px; --gap:12px; } }

*{box-sizing:border-box}
html{scroll-behavior:smooth}
@media (prefers-reduced-motion:reduce){ html{scroll-behavior:auto} }
body{
  margin:0;background:var(--page);color:var(--fg-1);
  font:16px/1.65 var(--ui);
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
h1,h2,h3,h4{margin:0;line-height:1.12;letter-spacing:-.022em;font-weight:680}
p{margin:0 0 1em}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:4px}
.wrap{max-width:var(--maxw);margin-inline:auto;padding-inline:24px}
.sr{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;
  clip:rect(0 0 0 0);white-space:nowrap;border:0}

/* ---------------------------------------------------------------- nav ---- */
nav{position:sticky;top:0;z-index:60;background:rgba(10,11,14,.82);
  backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);
  border-bottom:1px solid var(--line)}
nav .wrap{display:flex;align-items:center;gap:20px;height:56px}
.brand{display:flex;align-items:center;gap:9px;font-weight:750;font-size:17px;
  color:var(--fg-1);letter-spacing:-.03em}
.brand:hover{text-decoration:none}
.brand svg{width:24px;height:24px;flex:none}
nav .links{display:flex;gap:20px;margin-left:auto;font-size:14px}
nav .links a{color:var(--fg-2)}
nav .links a:hover{color:var(--fg-1);text-decoration:none}
nav .links a[aria-current=page]{color:var(--fg-1)}
@media (max-width:860px){ nav .links{display:none} }

.btn{display:inline-flex;align-items:center;gap:7px;padding:8px 13px;border-radius:9px;
  border:1px solid var(--line-2);background:rgba(255,255,255,.03);color:var(--fg-1);
  font:600 13.5px/1 var(--ui);white-space:nowrap;cursor:pointer;
  transition:background-color .13s,border-color .13s,color .13s}
.btn:hover{background:rgba(255,255,255,.07);text-decoration:none}
.btn.primary{background:var(--accent);border-color:transparent;color:#04211a}
.btn.primary:hover{filter:brightness(1.07)}
.btn svg{width:15px;height:15px}

/* --------------------------------------------------------------- hero ---- */
.hero{padding:28px 0 0;position:relative}
.hero::before{content:"";position:absolute;inset:-140px 0 auto;height:520px;pointer-events:none;
  background:radial-gradient(60% 60% at 50% 0%,rgba(34,211,165,.10),transparent 70%)}
.hero .wrap{position:relative}
.eyebrow{display:inline-flex;align-items:center;gap:8px;font:600 11px/1 var(--mono);
  letter-spacing:.16em;text-transform:uppercase;color:var(--accent);margin-bottom:14px}
.eyebrow i{width:5px;height:5px;border-radius:50%;background:var(--accent)}
.hero h1{font-size:clamp(34px,4.6vw,56px);font-weight:760;letter-spacing:-.04em;margin-bottom:4px}
.hero .subtitle{font-size:clamp(17px,1.9vw,22px);font-weight:480;color:var(--fg-1);
  letter-spacing:-.018em;line-height:1.25;margin-bottom:11px;max-width:none}
.hero .deck{font-size:clamp(16px,1.5vw,18.5px);color:var(--fg-2);max-width:96ch;margin-bottom:12px;
  font-weight:420;letter-spacing:-.008em}
.hero .deck b{color:var(--fg-1);font-weight:600}
.byline{font-size:12.5px;color:var(--fg-2);line-height:1.55;max-width:none}
.byline sup{color:var(--accent);font-size:9.5px}
.byline .aff{color:var(--fg-3);font-size:11.5px}

/* -------------------------------------------------------------- stage ---- */
.stage-sec{padding:18px 0 0}
.stage-hd{display:flex;align-items:baseline;gap:14px;flex-wrap:wrap;margin-bottom:12px}
.stage-hd h2{font-size:clamp(21px,2.3vw,29px);letter-spacing:-.028em}
.stage-hd{flex-direction:column;align-items:flex-start;gap:5px}
.stage-hd .sub{font-size:14.5px;color:var(--fg-2)}

.stage,.stage-w{width:min(var(--maxw),var(--fit-w,var(--stage-w)),100% - 48px);margin-inline:auto}
.pair-labels{display:grid;grid-template-columns:1fr 1fr;gap:var(--gap);margin-bottom:7px}
.pair-labels div{display:flex;align-items:baseline;gap:8px;font-size:12.5px;min-width:0}
.pair-labels .nm{font:650 12px/1 var(--mono);letter-spacing:.09em;text-transform:uppercase}
.pair-labels .base .nm{color:var(--fg-2)}
.pair-labels .veri .nm{color:var(--accent)}
.pair-labels .note{color:var(--fg-3);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}

.pair{display:grid;grid-template-columns:1fr 1fr;gap:var(--gap)}
.frame{position:relative;aspect-ratio:16/9;width:100%;border-radius:var(--r);overflow:hidden;
  background:#000 center/cover no-repeat;border:1px solid var(--line);
  contain:layout paint;isolation:isolate;cursor:pointer}
.frame video{position:absolute;inset:0;width:100%;height:100%;display:block;object-fit:cover;
  opacity:0;transition:opacity .22s linear}
[data-ready="1"] .frame video{opacity:1}
@media (prefers-reduced-motion:reduce){ .frame video{transition-duration:1ms} }
.frame .side{position:absolute;left:9px;top:9px;z-index:2;
  font:650 10.5px/1 var(--mono);letter-spacing:.1em;text-transform:uppercase;
  padding:5px 8px;border-radius:6px;background:rgba(6,8,11,.72);
  backdrop-filter:blur(6px);-webkit-backdrop-filter:blur(6px)}
.frame.base .side{color:var(--fg-2);border:1px solid var(--line)}
.frame.veri .side{color:var(--accent);border:1px solid var(--accent-line)}

.transport{display:flex;align-items:center;gap:12px;margin-top:11px}
.pp{width:34px;height:34px;flex:none;display:grid;place-items:center;border-radius:8px;
  border:1px solid var(--line-2);background:rgba(255,255,255,.04);color:var(--fg-1);cursor:pointer}
.pp:hover{background:rgba(255,255,255,.08)}
.pp svg{width:13px;height:13px;fill:currentColor}
.pp .i-pause{display:none}
.pp[data-state=playing] .i-play{display:none}
.pp[data-state=playing] .i-pause{display:block}
.transport input[type=range]{flex:1;height:4px;-webkit-appearance:none;appearance:none;
  background:var(--line-2);border-radius:2px;cursor:pointer}
.transport input[type=range]::-webkit-slider-thumb{-webkit-appearance:none;width:13px;height:13px;
  border-radius:50%;background:var(--accent);border:none;cursor:pointer}
.transport input[type=range]::-moz-range-thumb{width:13px;height:13px;border-radius:50%;
  background:var(--accent);border:none;cursor:pointer}
.transport .t{font:500 12px/1 var(--mono);color:var(--fg-3);
  font-variant-numeric:tabular-nums;min-width:84px;text-align:right}

/* -------------------------------------------------------- switcher rail -- */
.rail{display:grid;grid-template-columns:repeat(auto-fit,minmax(148px,1fr));gap:8px;margin-top:14px}
.chip{display:flex;align-items:center;gap:7px;min-height:40px;padding:8px 12px;
  border:1px solid var(--line);border-radius:999px;background:var(--panel);
  font:500 13.5px/1.2 var(--ui);color:var(--fg-2);text-align:left;cursor:pointer;min-width:0;
  transition:background-color .12s,border-color .12s,color .12s}
.chip:hover{background:var(--panel-2);color:var(--fg-1)}
.chip .lb{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
/* Selected changes colour only - never weight, padding or border-width - so the
   row cannot reflow and shove the next chip out from under the cursor. */
.chip[aria-pressed=true]{background:var(--accent-soft);border-color:var(--accent-line);color:var(--fg-1)}
.chip.ghost{border-style:dashed;color:var(--fg-2);justify-content:center}
.chip.ghost:hover{color:var(--accent);border-color:var(--accent-line);text-decoration:none}
@media (max-width:720px){
  .rail{display:flex;overflow-x:auto;scroll-snap-type:x proximity;scrollbar-width:none;padding-bottom:2px}
  .rail::-webkit-scrollbar{display:none}
  .chip{flex:0 0 auto;scroll-snap-align:start}
  .rail::after{content:"";flex:0 0 8px}
}

/* ------------------------------------------------------- clip metadata --- */
.meta{margin-top:26px}
.watch{display:flex;align-items:flex-start;gap:10px;font-size:16px;color:var(--fg-1);
  min-height:2.6rem;margin-bottom:16px}
.watch .eye{flex:none;margin-top:3px;color:var(--accent)}
.metagrid{display:grid;grid-template-columns:1.25fr 1fr;gap:var(--gap)}
@media (max-width:900px){ .metagrid{grid-template-columns:1fr} }
.card{background:var(--panel);border:1px solid var(--line);border-radius:var(--r);padding:18px 19px}
.card h3{font:650 11px/1 var(--mono);letter-spacing:.13em;text-transform:uppercase;
  color:var(--fg-3);margin-bottom:11px}
.prompt{font-size:14.5px;color:var(--fg-1);line-height:1.62;min-height:3.1rem}
.scores{display:flex;flex-wrap:wrap;gap:8px;margin-top:14px}
.pill{display:inline-flex;align-items:center;gap:7px;padding:6px 11px;border-radius:999px;
  border:1px solid var(--line);background:var(--panel-2);font:500 12.5px/1 var(--ui);color:var(--fg-2)}
.pill b{color:var(--fg-1);font-weight:650;font-variant-numeric:tabular-nums}
.pill.up{border-color:var(--accent-line);color:var(--fg-1)}
.pill.up b{color:var(--accent)}

.fails{list-style:none;margin:0;padding:0;display:grid;gap:12px}
.fails li{display:grid;grid-template-columns:auto 1fr;gap:10px;align-items:start;
  font-size:13.5px;line-height:1.55;color:var(--fg-2)}
.fails .eid{font:600 10.5px/1.5 var(--mono);color:var(--serious);
  border:1px solid rgba(236,131,90,.35);border-radius:5px;padding:2px 6px;white-space:nowrap}
.fails .as{color:var(--fg-1);display:block;margin-bottom:3px}
/* The claim is that every verdict keeps its receipt, so the measurement is
   always present - clamped to three lines until asked for, never removed. */
.fails .why{display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}
.card:has(details.records[open]) .fails .why{-webkit-line-clamp:unset;overflow:visible}
details.disclose{margin-top:16px;border-top:1px solid var(--line);padding-top:14px}
details.disclose summary{cursor:pointer;font:600 13px/1 var(--ui);color:var(--fg-2);
  list-style:none;display:flex;align-items:center;gap:8px}
details.disclose summary::-webkit-details-marker{display:none}
details.disclose summary::before{content:"+";font-family:var(--mono);color:var(--accent);font-size:15px}
details.disclose[open] summary::before{content:"\2013"}
details.disclose summary:hover{color:var(--fg-1)}
.newprompt{margin-top:12px;font-size:13.5px;line-height:1.65;color:var(--fg-2);
  background:var(--panel-2);border:1px solid var(--line);border-radius:9px;padding:14px 15px}

/* ------------------------------------------------------------ sections --- */
section{padding:76px 0}
.sec-k{font:650 11px/1 var(--mono);letter-spacing:.15em;text-transform:uppercase;
  color:var(--accent);margin-bottom:13px}
.sec-h{font-size:clamp(25px,3.1vw,38px);letter-spacing:-.03em;margin-bottom:14px;max-width:22ch}
.sec-d{font-size:17px;color:var(--fg-2);max-width:70ch}
.alt{background:linear-gradient(180deg,rgba(148,163,184,.035),transparent);
  border-top:1px solid var(--line);border-bottom:1px solid var(--line)}

/* The bridge: one sentence, no heading, turning the page from demo to method. */
.bridge{padding:64px 0;text-align:center}
.bridge p{font-size:clamp(20px,2.6vw,31px);line-height:1.35;letter-spacing:-.028em;
  color:var(--fg-2);max-width:27ch;margin:0 auto;font-weight:500}
.bridge b{color:var(--fg-1);font-weight:650}

.beats{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--gap);margin-top:38px}
@media (max-width:1000px){ .beats{grid-template-columns:repeat(2,1fr)} }
@media (max-width:620px){ .beats{grid-template-columns:1fr} }
.beat{background:var(--panel);border:1px solid var(--line);border-radius:var(--r);padding:20px}
.beat .n{font:600 10.5px/1 var(--mono);letter-spacing:.13em;color:var(--fg-3);margin-bottom:13px}
.beat h3{font-size:17px;margin-bottom:9px;letter-spacing:-.02em}
.beat p{font-size:14px;color:var(--fg-2);margin:0;line-height:1.6}
.verdict-words{display:flex;gap:6px;flex-wrap:wrap;margin-top:13px}
.vw{font:600 11px/1 var(--mono);padding:5px 8px;border-radius:6px;border:1px solid var(--line);color:var(--fg-2)}
.vw.ok{color:var(--accent);border-color:var(--accent-line)}
.vw.no{color:var(--serious);border-color:rgba(236,131,90,.35)}
.vw.ab{color:var(--warn);border-color:rgba(250,178,25,.35)}

.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:var(--gap);margin-top:36px}
@media (max-width:1000px){ .stats{grid-template-columns:repeat(2,1fr)} }
@media (max-width:560px){ .stats{grid-template-columns:1fr} }
.stat{background:var(--panel);border:1px solid var(--line);border-radius:var(--r);padding:18px 19px}
.stat .v{font-size:33px;font-weight:700;letter-spacing:-.035em;font-variant-numeric:tabular-nums;
  line-height:1.05;margin-bottom:5px}
.stat .v small{font-size:15px;font-weight:500;color:var(--fg-3);margin-left:5px;letter-spacing:-.01em}
.stat .l{font-size:13.5px;color:var(--fg-2);line-height:1.5;min-height:2.9em}
.stat .track{height:4px;border-radius:2px;background:rgba(148,163,184,.16);margin-top:13px;overflow:hidden}
.stat .track i{display:block;height:100%;border-radius:2px;background:var(--accent)}
.stat.muted .v{color:var(--fg-2)}
.stat.muted .track i{background:var(--fg-3)}

table.cmp{width:100%;border-collapse:collapse;margin-top:16px;font-size:13.5px}
table.cmp th,table.cmp td{padding:9px 10px;text-align:right;border-bottom:1px solid var(--line);
  font-variant-numeric:tabular-nums}
table.cmp th:first-child,table.cmp td:first-child{text-align:left;color:var(--fg-2)}
table.cmp thead th{font:650 11px/1.35 var(--mono);letter-spacing:.06em;text-transform:uppercase;
  color:var(--fg-3);vertical-align:bottom}
table.cmp tbody td{color:var(--fg-1)}
table.cmp tr.hl td{background:rgba(148,163,184,.05)}
.fine{font-size:12.5px;color:var(--fg-3);line-height:1.6;margin-top:14px}

/* Single-hue comparison bars: this is magnitude, so one hue with the subject
   emphasised - not a categorical palette. */
.bars{display:grid;gap:15px;margin-top:20px}
.bar-row .top{display:flex;justify-content:space-between;align-items:baseline;gap:12px;
  font-size:13.5px;color:var(--fg-2);margin-bottom:7px}
.bar-row .top b{color:var(--fg-1);font-weight:650;font-variant-numeric:tabular-nums}
.bar-row .track{height:9px;border-radius:5px;background:rgba(148,163,184,.13);overflow:hidden}
.bar-row .track i{display:block;height:100%;border-radius:5px;background:rgba(148,163,184,.45)}
.bar-row.me .top{color:var(--fg-1)}
.bar-row.me .track i{background:var(--accent)}

/* ------------------------------------------------------------- footer ---- */
footer{border-top:1px solid var(--line);padding:58px 0 70px;background:rgba(148,163,184,.02)}
footer .cols{display:grid;grid-template-columns:1.35fr 1fr;gap:44px}
@media (max-width:860px){ footer .cols{grid-template-columns:1fr} }
footer h4{font:650 11px/1 var(--mono);letter-spacing:.13em;text-transform:uppercase;
  color:var(--fg-3);margin-bottom:14px}
pre.bib{margin:0;background:var(--panel);border:1px solid var(--line);border-radius:var(--r);
  padding:16px;overflow-x:auto;font:12px/1.65 var(--mono);color:var(--fg-2);white-space:pre}
footer ul{list-style:none;margin:0 0 18px;padding:0;display:grid;gap:9px;font-size:14px}
footer ul a{color:var(--fg-2)}
footer ul a:hover{color:var(--accent)}

/* ------------------------------------------------------------ gallery ---- */
.group{margin-top:52px}
.group h3{font-size:clamp(20px,2.2vw,26px);letter-spacing:-.028em;margin-bottom:7px}
.group .gloss{font-size:14.5px;color:var(--fg-2);max-width:66ch;margin-bottom:20px}
.cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(268px,1fr));gap:var(--gap);
  content-visibility:auto;contain-intrinsic-size:auto 320px}
.gcard{display:flex;flex-direction:column;background:var(--panel);border:1px solid var(--line);
  border-radius:var(--r);overflow:hidden;text-align:left;cursor:pointer;color:inherit;padding:0;
  transition:border-color .13s,transform .13s;font:inherit}
.gcard:hover{border-color:var(--accent-line);text-decoration:none;transform:translateY(-2px)}
@media (prefers-reduced-motion:reduce){ .gcard:hover{transform:none} }
.gcard .shots{display:grid;grid-template-columns:1fr 1fr;gap:2px;background:var(--line)}
.gcard .shot{position:relative;aspect-ratio:16/9;background:#000 center/cover no-repeat}
.gcard .shot span{position:absolute;left:6px;top:6px;font:650 9px/1 var(--mono);letter-spacing:.09em;
  text-transform:uppercase;padding:4px 6px;border-radius:4px;background:rgba(6,8,11,.74);color:var(--fg-2)}
.gcard .shot.veri span{color:var(--accent)}
.gcard .body{display:block;padding:14px 15px 16px}
.gcard .lb{display:block;font-size:15px;font-weight:640;letter-spacing:-.018em;margin-bottom:5px}
.gcard .wt{display:block;font-size:13px;color:var(--fg-2);line-height:1.5}
.gcard .play{margin-top:11px;font:600 12px/1 var(--ui);color:var(--accent);display:flex;align-items:center;gap:6px}

/* On a phone two 16:9 clips plus labels and transport cannot leave room for the
   rail below the fold, so the rail moves above the stage. The transport stays
   with the clips it drives. */
/* The rail is a control strip, not part of the picture, so it keeps the full
   page measure even when the stage has been narrowed to fit the fold —
   otherwise the chip labels, which carry the argument, start truncating. */
.stage-sec{display:flex;flex-direction:column}
.stage-sec > .stage-hd{order:1}
.stage-sec > .stage{order:2}
.stage-sec > .railwrap{order:3}
.stage-sec > .meta{order:4}
.railwrap{width:min(var(--maxw),100% - 48px);margin:14px auto 0}
.railwrap .rail{margin-top:0}
@media (max-width:720px){
  .stage-sec > .stage-hd{order:0}
  .stage-sec > .railwrap{order:1;margin:0 auto 14px}
  .pair{grid-template-columns:1fr}
}

/* Short laptops: the fold has to hold the demo AND the switcher, so the hero
   gives up its ornament rather than the clip giving up its size. The in-frame
   badges already name each side, so the label row above the stage is redundant
   here. */
@media (min-width:721px) and (max-height:850px){
  .hero{padding-top:16px}
  .hero .eyebrow{display:none}
  .hero h1{font-size:clamp(26px,3.4vw,38px);margin-bottom:2px}
  .hero .subtitle{font-size:17px;margin-bottom:7px}
  .hero .deck{font-size:15.5px;margin-bottom:9px;max-width:118ch}
  .byline{font-size:11.5px;line-height:1.45}
  .byline .aff{font-size:10.5px}
  .stage-sec{padding-top:10px}
  .stage-hd{margin-bottom:8px}
  .stage-hd h2{font-size:clamp(18px,2vw,23px)}
  .pair-labels{display:none}
  .transport{margin-top:9px}
  .rail{margin-top:10px}
}

@media (max-width:720px){
  /* the in-frame badges already name each side; the label row only wraps here */
  .pair-labels{display:none}
  .hero{padding-top:20px}
  .hero .deck{font-size:16px;line-height:1.5}
  .hero .subtitle{font-size:17px;max-width:none}
  .byline{font-size:11.5px;line-height:1.5}
  .byline .aff{font-size:10.5px}
  .stage-hd h2{font-size:20px}
  .stage-hd .sub{display:none}
  section{padding:52px 0}
  .bridge{padding:44px 0}
  .metagrid{gap:14px}
}