/* iSEE project page. One file, no framework, system fonts, no external request. */
:root{
  --fg:#1b1d1f; --muted:#5d636a; --faint:#8a9097; --line:#e3e5e8; --soft:#f5f6f7;
  --accent:#1c7c45; --slot:#29A85A; --hid:#9aa0a6; --dark:#1f2328;
  --text:760px; --wide:1040px;
  color-scheme:light;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{margin:0;background:#fff;color:var(--fg);
  font:16px/1.6 system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
img,video{display:block;max-width:100%;height:auto}
.wrap{max-width:var(--wide);margin:0 auto;padding:0 24px}
.text{max-width:var(--text);margin-inline:auto}

/* header */
.hero{text-align:center;padding:64px 0 0}
h1{font-size:clamp(28px,4.4vw,44px);line-height:1.15;margin:0;font-weight:700;letter-spacing:-.012em;text-wrap:balance}
.authors{margin:20px 0 0;font-size:18px;display:flex;flex-wrap:wrap;justify-content:center;gap:4px 22px}
.authors a,.authors span{color:var(--fg)}
.authors sup{color:var(--muted);font-size:11px;margin-left:1px}
.affils{margin:6px 0 0;color:var(--muted);font-size:15px}
.affils sup{font-size:10px;margin-right:2px}
.venue{margin:8px 0 0;font-weight:600;font-size:16px}
.logos{display:flex;justify-content:center;align-items:center;gap:28px;margin:18px 0 0}
.logos img{height:60px;width:auto}
.buttons{display:flex;flex-wrap:wrap;justify-content:center;gap:10px;margin:24px 0 0}
.btn{display:inline-flex;align-items:center;gap:8px;padding:8px 17px;border-radius:999px;
  background:var(--dark);color:#fff;font-size:15px;font-weight:500;line-height:1.4}
.btn:hover{background:#000;text-decoration:none}
.btn svg{width:17px;height:17px;fill:currentColor;flex:none}
.btn[aria-disabled=true]{background:var(--soft);color:var(--faint);box-shadow:inset 0 0 0 1px var(--line);cursor:default}
.btn .soon{font-size:12px}

/* sections */
section{padding:56px 0 0}
h2{font-size:26px;line-height:1.25;margin:0 0 18px;text-align:center;font-weight:700;letter-spacing:-.005em}
h3{font-size:18px;line-height:1.3;margin:40px 0 14px;text-align:center;font-weight:600}
p{margin:0 0 14px}
.lead{font-size:18px;line-height:1.55;text-align:center;margin:22px auto 0;max-width:var(--text);text-wrap:pretty}
.abstract p{text-wrap:pretty}
figure{margin:0}
.fig img{width:100%}
.caption,figcaption.caption{font-size:14.5px;line-height:1.55;color:var(--muted);margin:12px auto 0;max-width:var(--text)}
.caption b{color:var(--fg);font-weight:600}
.method-list{margin:22px auto 0;max-width:var(--text);padding:0;list-style:none;display:grid;gap:14px}
.method-list li{padding-left:16px;border-left:3px solid var(--slot)}
.method-list b{font-weight:650}
.figrow{display:flex;align-items:center;gap:26px}
.figrow .sep{align-self:stretch;width:1px;background:var(--line);flex:none}

/* object-permanence hook */
.hook{text-align:center;padding-top:60px}
.kicker{margin:0 0 10px;font-size:13px;font-weight:650;letter-spacing:.14em;text-transform:uppercase;color:var(--accent)}
.display{font-size:clamp(34px,5.6vw,56px);line-height:1.05;font-weight:800;letter-spacing:-.025em;margin:0}
.hook .lead{margin-top:18px}
.ytgrid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px;margin:34px auto 0;text-align:left}
.yt{display:block;position:relative;width:100%;aspect-ratio:16/9;border:0;border-radius:8px;overflow:hidden;background:#111}
.yt img{width:100%;height:100%;object-fit:cover}
.yt .play{position:absolute;left:50%;top:50%;width:60px;height:42px;transform:translate(-50%,-50%);transition:transform .15s}
a.yt:hover .play{transform:translate(-50%,-50%) scale(1.08)}
.ytfig figcaption{font-size:14.5px;line-height:1.45;color:#33373b;margin-top:8px}
.ytfig .credit{display:block;font-size:12.5px;color:var(--faint);margin-top:2px}
.pivot{max-width:var(--text);margin:40px auto 0;font-size:19px;line-height:1.5;text-wrap:pretty}
.hook .note{margin:10px auto 0}
.hook + .teaser{margin-top:30px}

/* legend */
.legend{display:flex;flex-wrap:wrap;justify-content:center;gap:8px 22px;margin:0 auto 26px;font-size:14px;color:var(--muted)}
.legend .li{display:inline-flex;align-items:center;gap:7px}
.legend svg{flex:none;display:block}
.note{font-size:14px;color:var(--faint);text-align:center;margin:-12px auto 22px;max-width:var(--text)}

/* clips */
.grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:30px 22px}
.clip{min-width:0}
.clip .frame{position:relative;background:#8E8F8C;border-radius:6px;overflow:hidden}
.clip video,.clip img{width:100%;height:auto}
.clip figcaption{font-size:14.5px;color:#33373b;text-align:center;margin-top:7px}
.clip figcaption .dur{color:var(--faint)}
.tl{position:relative;height:8px;margin-top:8px;border-radius:4px;background:var(--line);overflow:hidden;cursor:pointer;touch-action:manipulation}
.tl i{position:absolute;top:0;bottom:0;background:var(--hid)}
.tl .ph{position:absolute;top:0;bottom:0;left:0;width:2px;margin-left:-1px;background:var(--fg)}
.quad .lab{position:absolute;font-size:12.5px;line-height:1;color:#fff;background:rgba(0,0,0,.55);
  padding:4px 7px;border-radius:3px;pointer-events:none}
.quad .lab.ours{background:var(--slot)}
.teaser{max-width:880px;margin:44px auto 0}
.teaser.single{max-width:720px}
.grid>:last-child:nth-child(odd){grid-column:1/-1;justify-self:center;width:calc(50% - 11px)}

/* comparison tabs (JS adds .js-tabs; without JS every clip is shown) */
.tabbar{display:flex;justify-content:center;flex-wrap:wrap;gap:8px;margin:0 0 16px}
.tabbar button{font:inherit;font-size:14.5px;padding:6px 14px;border-radius:999px;border:1px solid var(--line);
  background:#fff;color:var(--fg);cursor:pointer}
.tabbar button[aria-selected=true]{background:var(--dark);border-color:var(--dark);color:#fff}
.stack{display:grid;gap:32px;max-width:880px;margin:0 auto}

/* table */
.tablewrap{overflow-x:auto;max-width:var(--text);margin:0 auto}
table{border-collapse:collapse;width:100%;min-width:560px;font-size:14.5px;font-variant-numeric:tabular-nums}
thead tr:first-child th{border-top:2px solid var(--fg)}
th,td{padding:5px 8px;text-align:center;white-space:nowrap}
th:first-child,td:first-child{text-align:left}
thead th{font-weight:600}
thead tr:last-child th{border-bottom:1px solid var(--fg);font-weight:500;color:var(--muted)}
thead .grp{border-bottom:1px solid var(--line)}
tbody.g+tbody.g tr:first-child td{border-top:1px solid var(--line)}
tbody:last-child tr:last-child td{border-bottom:2px solid var(--fg)}
tr.priv td{color:var(--faint);background:var(--soft)}
tr.ours td{font-weight:500}
td b{font-weight:700}

/* failures */
details{max-width:var(--wide);margin:0 auto}
summary{cursor:pointer;list-style:none;text-align:center;font-size:26px;font-weight:700;line-height:1.25}
summary::-webkit-details-marker{display:none}
summary::after{content:"";display:inline-block;width:9px;height:9px;margin:0 0 5px 12px;border-right:2.5px solid currentColor;
  border-bottom:2.5px solid currentColor;transform:rotate(45deg);transition:transform .15s}
details[open] summary::after{transform:rotate(225deg);margin-bottom:0}
summary .count{color:var(--faint);font-weight:500}
details .inner{padding-top:22px}

/* bibtex */
.bib{position:relative;max-width:var(--text);margin:0 auto}
.bib pre{margin:0;padding:16px 18px;background:var(--soft);border:1px solid var(--line);border-radius:8px;
  font:13.5px/1.55 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;overflow-x:auto;white-space:pre}
.bib button{position:absolute;top:10px;right:10px;font:inherit;font-size:13px;padding:4px 11px;border-radius:6px;
  border:1px solid var(--line);background:#fff;color:var(--fg);cursor:pointer}

footer{margin:72px 0 0;padding:22px 0 40px;border-top:1px solid var(--line);text-align:center;font-size:13.5px;color:var(--faint)}

@media (max-width:720px){
  .wrap{padding:0 16px}
  .hero{padding-top:40px}
  .authors{font-size:16.5px}
  .logos img{height:48px}
  section{padding-top:44px}
  h2,summary{font-size:22px}
  .grid{grid-template-columns:minmax(0,1fr)}
  .grid>:last-child:nth-child(odd){width:100%}
  .ytgrid{grid-template-columns:none;grid-auto-flow:column;grid-auto-columns:80%;gap:14px;overflow-x:auto;
    scroll-snap-type:x mandatory;margin-inline:-16px;padding:0 16px 6px;scroll-padding-inline:16px}
  .ytfig{scroll-snap-align:start}
  .hook .lead,.pivot{text-align:left}
  .pivot{font-size:17px}
  .hook .note{text-align:left}
  .figrow{flex-direction:column;gap:18px}
  .figrow .sep{display:none}
  .quad .lab{font-size:10px;padding:3px 4px}
  .lead{font-size:16.5px}
}