@font-face{font-family:Lato;src:url('../fonts/Lato-Regular.ttf') format('truetype');font-weight:400;font-display:swap}@font-face{font-family:Lato;src:url('../fonts/Lato-Bold.ttf') format('truetype');font-weight:700;font-display:swap}
:root{--ink:#171c22;--muted:#616972;--line:#e6e4df;--accent:#9b531f;--tint:#f8e9d7;--soft:#faf9f6;--blue:#5d788a;--radius:12px}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:95px}body{margin:0;background:#fff;color:var(--ink);font-family:Lato,Arial,sans-serif;font-size:16px;line-height:1.6}button,a,video{-webkit-tap-highlight-color:transparent}button{font:inherit;cursor:pointer}a{color:inherit;text-decoration:none}button:focus-visible,a:focus-visible,summary:focus-visible{outline:3px solid #d4945e;outline-offset:4px}button{color:var(--ink)}[hidden]{display:none!important}.wrap{max-width:1200px;margin:0 auto;padding:0 32px}header{position:sticky;top:0;z-index:15;background:rgba(255,255,255,.96);border-bottom:1px solid var(--line);backdrop-filter:blur(12px)}.nav-wrap{max-width:1320px;margin:auto;min-height:74px;display:flex;align-items:center;justify-content:space-between;padding:12px 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var(--line);display:flex;justify-content:space-between;align-items:center;font-size:12px;color:var(--muted)}footer .brand{color:var(--ink)}.noscript{text-align:center;background:var(--tint);padding:20px}.video-stage.failed::after{content:'Video unavailable';position:absolute;padding:8px;color:#995d38;background:var(--soft);font-size:12px}
@media(min-width:1200px){.hero-group .video-stage{height:250px}}
@media(max-width:900px){nav{gap:13px;font-size:11px}.brand i{display:none}.nav-wrap{min-height:62px}.wrap{padding-left:24px;padding-right:24px}.hero{padding-top:42px}.cols-5{grid-template-columns:repeat(3,minmax(0,1fr))}.cols-4{grid-template-columns:repeat(2,minmax(0,1fr))}.hero-group .video-stage{height:auto}.mode-selector{grid-template-columns:repeat(4,1fr)}.mode-selector button{display:block}.mode-selector button span{display:block;margin-top:4px}.explanation{gap:25px}.equation strong{font-size:20px}.stage-nav{gap:10px}.stage-nav a{font-size:11px}.section-heading h2{font-size:28px}}
@media(max-width:600px){.nav-wrap{display:block;padding:12px 18px}.brand{font-size:21px}nav{overflow-x:auto;white-space:nowrap;gap:19px;margin-top:7px;padding-bottom:2px;font-size:11px}.wrap{padding-left:18px;padding-right:18px}.hero{padding-top:34px}h1{font-size:55px;letter-spacing:-2.5px}.paper-title{font-size:20px}.intro{font-size:14px}.hero-actions{margin:21px 0}.hero-group .video-grid{gap:6px}.hero-group .video-label{padding:8px 6px}.hero-group .video-label strong{font-size:10px}.hero-group .video-label span{font-size:9px}.stats b{font-size:24px}.stats span{font-size:10px}.stats{margin-top:20px;padding-top:22px}.section{padding-top:43px}.section-heading{gap:12px;padding-top:24px}.section-number{width:30px;height:30px;font-size:11px}.section-heading h2{font-size:25px}.section-heading p{font-size:14px}.mode-selector{grid-template-columns:repeat(2,1fr);gap:7px}.mode-selector button{display:flex;align-items:center;padding:10px}.mode-selector button span{margin:0;font-size:10px}.mode-panel{padding:14px}.mode-heading h3{font-size:17px}.mode-heading p{font-size:12px}.mode-count b{font-size:19px}.mode-count span{font-size:9px}.mode-heading{gap:10px}.cols-5,.cols-3:not(.hero-group .cols-3){grid-template-columns:repeat(2,minmax(0,1fr))}.hero-group .cols-3{grid-template-columns:repeat(3,minmax(0,1fr))}.video-grid{gap:8px}.video-label{padding:8px}.video-label strong{font-size:11px}.video-label span{font-size:9px}.group-note{font-size:10px;text-align:left}.bank-tools{font-size:10px;gap:10px}.bank-tools button{font-size:10px}.subdetails{padding:0 12px}.subdetails summary{font-size:12px}.subdetails summary span{font-size:10px;margin-left:5px}.explanation{grid-template-columns:1fr;padding:20px;gap:20px}.equation{border-left:0;border-top:1px solid var(--line);padding:20px 0 0}.stage-nav{align-items:stretch;padding:13px 10px;gap:7px}.stage-nav a{display:block;font-size:10px;flex:1;text-align:center;line-height:1.3}.stage-nav b{margin:0 auto 5px}.stage-nav>span{align-self:center}.comparison-context{grid-template-columns:1fr;gap:12px}.failure-layout{grid-template-columns:1fr;gap:22px}footer{flex-wrap:wrap;gap:15px}.stage-caption h3{font-size:21px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
.reading-grid{display:grid;grid-template-columns:1fr 1fr;gap:28px;margin:28px 0}.reading-grid article{padding:20px 0;border-top:1px solid var(--line)}.reading-grid h3{font-size:18px;line-height:1.4;margin:6px 0 10px}.reading-grid p{font-size:14px;color:var(--muted);margin:0;line-height:1.75}.bank-intro{margin-top:0}.bank-intro article{border:0;padding-top:0}.scope-note{background:var(--soft);border-left:3px solid #caaa8e;padding:17px 22px;margin:24px 0;font-size:14px;color:var(--muted);line-height:1.75}.scope-note strong{color:var(--ink)}@media(max-width:600px){.reading-grid{grid-template-columns:1fr;gap:6px}.reading-grid article{padding:15px 0}.scope-note{padding:15px 17px}}

.video-stage video{pointer-events:none;user-select:none}.group-note{margin:0 0 9px;text-align:left}

.mode-selector{display:flex;overflow-x:auto;gap:8px;padding-bottom:10px;scroll-snap-type:x proximity}.mode-selector button{flex:0 0 174px;scroll-snap-align:start;display:flex}.mode-panel .video-grid{display:flex;overflow-x:auto;gap:12px;padding-bottom:12px;scroll-snap-type:x proximity}.mode-panel .video-card{flex:0 0 205px;scroll-snap-align:start}.mode-panel .video-stage{height:205px;aspect-ratio:1}.comparison-explanation{grid-template-columns:1fr}.comparison-explanation article{max-width:850px}@media(max-width:600px){.mode-selector button{flex-basis:155px}.mode-panel .video-card{flex-basis:185px}.mode-panel .video-stage{height:185px}}

.hero{padding-top:40px}.hero .authors{margin-bottom:0}.mode-selector a{flex:0 0 180px;display:flex;gap:10px;padding:12px;border:1px solid var(--line);border-radius:8px;align-items:center}.mode-selector a span{font-size:11px;line-height:1.3}.mode-selector a b{color:var(--accent)}.mode-heading{justify-content:flex-start;align-items:center}.mode-heading h3{font-size:18px}.mode-badge{margin:0}.pair-scroll{overflow-x:auto;padding-bottom:12px;margin-top:16px}.pair-scroll h4{position:sticky;left:0;font-size:12px;color:var(--muted);font-weight:400;margin:14px 0 8px;width:max-content}.pose-strip{display:flex;gap:12px;width:max-content}.pose-strip .video-card{width:205px;flex:none}.pose-strip .video-stage{height:205px}.pose-strip .video-label{text-align:center}.horizontal .video-grid{display:flex;overflow-x:auto;gap:12px;padding-bottom:14px;scroll-snap-type:x proximity}.horizontal .video-card{flex:0 0 210px;scroll-snap-align:start}.geometry-strip .video-stage{height:210px;aspect-ratio:1}.scene-strip .video-card{flex-basis:260px}.sequence-control{display:flex;align-items:center;gap:18px;border-bottom:1px solid var(--line);padding:0 0 24px;margin-bottom:28px}.sequence-control label{font-size:13px;font-weight:700}.sequence-control select{font:inherit;font-size:14px;min-width:280px;max-width:100%;padding:12px 40px 12px 14px;border:1px solid #caaa8e;border-radius:7px;background:var(--soft);color:var(--ink)}.sequence-heading{font-size:23px;margin-bottom:0}.sequence-heading span{font-size:12px;margin-left:10px;color:var(--accent)}.paired-stage-headings{display:grid;grid-template-columns:1fr 1fr;gap:12px}.stage-motion .video-stage{aspect-ratio:5/4}.stage-observations .video-stage{aspect-ratio:4/3}.stage-caption h3{font-size:20px}.stage-caption p{font-size:13px}.pipeline-panel{padding-bottom:30px;border-bottom:1px solid var(--line)}.failure-example{max-width:660px}.section> .mode-panel{margin-bottom:24px}.mode-panel{scroll-margin-top:100px}@media(max-width:600px){.pose-strip .video-card{width:170px}.pose-strip .video-stage{height:170px}.horizontal .video-card{flex-basis:185px}.geometry-strip .video-stage{height:185px}.sequence-control{display:block}.sequence-control label{display:block;margin-bottom:8px}.sequence-control select{width:100%;min-width:0}.paired-stage-headings h3{font-size:16px}.paired-stage-headings p{font-size:11px}.mode-heading h3{font-size:16px}.hero{padding-top:30px}}

.paired-stage-headings,.stage-motion,.stage-observations{max-width:680px}

.contents-wrap{margin-top:32px}.contents{display:block;white-space:normal;margin:0;padding:20px 0 0;border-top:1px solid var(--line);font-size:13px}.contents h2{font-size:14px;color:var(--ink);margin:0 0 14px}.contents ol,.contents ul{list-style:none;margin:0;padding:0}.contents-sections{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:12px}.contents-sections a{display:flex;gap:9px;align-items:baseline;color:var(--ink);font-weight:700}.contents-sections a span{color:var(--accent);font-size:11px;font-weight:400}.contents-detail{display:flex;align-items:baseline;gap:18px;margin-top:16px;font-size:12px}.contents-detail>span{flex:0 0 84px;color:var(--muted)}.contents-detail ul{display:flex;flex-wrap:wrap;column-gap:20px;row-gap:8px}.contents a:hover{text-decoration:underline;text-underline-offset:3px}.contents a:focus-visible{outline-offset:3px}
.video-loading{position:absolute;inset:auto auto 12px 50%;transform:translateX(-50%);display:none;align-items:center;gap:7px;white-space:nowrap;border:1px solid var(--line);border-radius:20px;background:rgba(255,255,255,.95);color:var(--muted);padding:6px 10px;font-size:11px;line-height:1.4;pointer-events:none}.video-stage.loading .video-loading{display:flex}.loading-spinner{width:12px;height:12px;flex:none;border:1.5px solid #ded9d2;border-top-color:var(--accent);border-radius:50%;animation:video-loading-spin .85s linear infinite}@keyframes video-loading-spin{to{transform:rotate(360deg)}}
@media(max-width:600px){.contents-sections{grid-template-columns:repeat(2,minmax(0,1fr));gap:12px 16px}.contents-detail{gap:12px;align-items:flex-start}.contents-detail>span{flex-basis:64px}.contents-detail ul{column-gap:14px;row-gap:8px}.contents-wrap{margin-top:26px}.contents-sections a{font-size:12px}}
@media(prefers-reduced-motion:reduce){.loading-spinner{animation:none}}

/* Full-width four-example stage rows. */
.stage-motion,.stage-observations{max-width:none;width:100%;margin-inline:0}.comparison-case{font-size:15px;font-weight:600;margin:24px 0 10px}.stage-caption p:empty{display:none}

.video-card .task-instruction{margin:0;padding:0 12px 14px;text-align:left;font-size:13px;line-height:1.55;color:var(--ink);font-weight:400}.task-instruction>span{display:block;margin-bottom:5px;font-size:11px;color:var(--muted);font-weight:400}