Stacked pull requests

<div class="demo files"><div class="heading"><strong>STACKED PRS</strong><span class="live">LIVE</span></div><div class="scene"><div class="diagram stack">
      <span class="box cue layer" data-cue="0">main</span><span class="box cue layer" data-cue="1">PR A · schema</span><span class="box cue layer" data-cue="2">PR B · API</span><span class="box cue layer" data-cue="3">PR C · UI</span>
      <span class="stack-note">each PR targets the layer below</span></div></div><div class="caption" id="caption"></div><div class="ticks"><i></i><i></i><i></i><i></i></div></div>

.demo{box-sizing:border-box;width:min(96vw,760px);height:min(94vh,330px);padding:clamp(9px,2vmin,18px);display:flex;flex-direction:column;gap:clamp(4px,1.2vmin,8px);border:1px solid var(--line);border-radius:13px;background:var(--surface);color:var(--fg);font:500 clamp(12px,3.4vmin,16px)/1.2 var(--font-sans,-apple-system),sans-serif}
.demo *{box-sizing:border-box}.heading{display:flex;align-items:center;justify-content:space-between;gap:8px;flex:none;min-height:18px}.heading strong{color:var(--accent);font-size:1em;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.live{flex:none;font:600 12px ui-monospace,monospace;color:var(--accent);letter-spacing:.08em}.live:before{content:'';display:inline-block;width:5px;height:5px;margin-right:4px;border-radius:50%;background:var(--accent);animation:blink 1.2s infinite}@keyframes blink{50%{opacity:.2}}
.scene{flex:1;min-height:0;overflow:hidden}.diagram{width:100%;height:100%;min-height:0;display:flex;align-items:center;justify-content:center;gap:4px}.box{display:flex;align-items:center;justify-content:center;min-width:0;min-height:25px;padding:3px 5px;border:1px solid var(--line);border-radius:6px;background:var(--bg);text-align:center;white-space:pre-line;overflow-wrap:anywhere;transition:background .25s,border-color .25s,transform .25s}.box.active,.cue.active{border-color:var(--accent);background:color-mix(in srgb,var(--accent) 16%,var(--surface));color:var(--fg)}.box.active{transform:scale(1.03)}.arrow{flex:none;color:var(--accent);font:700 17px/1 var(--font-sans),sans-serif}.caption{flex:none;min-height:2.3em;display:flex;align-items:center;justify-content:center;text-align:center;font-size:clamp(12px,3vmin,15px)}.ticks{flex:none;display:flex;justify-content:center;gap:4px}.ticks i{display:block;width:14px;height:3px;background:var(--line);border-radius:3px}.ticks i.active{background:var(--accent)}
.diagram b{font:700 12px/1.2 var(--font-sans),sans-serif;color:var(--muted)}.diagram small{font:500 12px/1.2 var(--font-sans),sans-serif}.empty{color:var(--muted)}
.worktrees{flex-direction:column;gap:0}.worktrees .store{width:82%;min-height:26px}.fork-line{width:53%;height:12px;border-left:2px solid var(--accent);border-right:2px solid var(--accent);border-top:2px solid var(--accent);transform:rotate(180deg);margin-top:1px}.folders{display:flex;width:100%;gap:7px;min-height:0;flex:1}.folder{display:flex;align-items:center;justify-content:center;gap:5px;flex:1;min-width:0;padding:3px;border:1px solid var(--line);border-radius:7px;background:var(--bg)}.folder .box{padding:2px 4px}.folder small{color:var(--muted)}
.stack{flex-direction:column;align-items:flex-start;gap:2px}.stack .layer{height:22px;min-height:0;justify-content:flex-start;padding-left:9px}.stack .layer:nth-child(1){width:70%}.stack .layer:nth-child(2){width:76%;margin-left:8%}.stack .layer:nth-child(3){width:76%;margin-left:16%}.stack .layer:nth-child(4){width:76%;margin-left:24%}.stack-note{position:absolute;opacity:0}
.context-map{display:grid;grid-template-columns:1.25fr 12px 1fr 12px 1.3fr;grid-template-rows:1fr 1fr;gap:3px}.context-map .diff{grid-column:1;grid-row:1/3}.context-map .arrow-a{grid-column:2;grid-row:1/3}.context-map .arrow-b{grid-column:4;grid-row:1/3}.context-map .arrow{display:grid;place-items:center}.context-map .upload{grid-column:3;grid-row:1}.context-map .sync{grid-column:3;grid-row:2}.context-map .test{grid-column:5;grid-row:1}.context-map .finding{grid-column:5;grid-row:2}.context-map .box{height:100%}
.policy{display:grid;grid-template-columns:1fr 16px 1fr 1.25fr;grid-template-rows:1fr 1fr;gap:3px}.policy .approval{grid-column:1;grid-row:1/3;height:100%}.policy>.arrow{grid-column:2;grid-row:1/3}.policy .ruleset{grid-column:3;grid-row:1/3;height:100%}.decisions{grid-column:4;grid-row:1/3;display:flex;flex-direction:column;gap:4px;height:100%}.decisions .box{flex:1;width:100%}.policy-note{display:none}
.rewrite{flex-direction:column;gap:2px}.history-row{display:flex;align-items:center;justify-content:center;gap:3px;width:100%;flex:1}.history-row>span:first-child{width:45px;flex:none;color:var(--muted)}.history-row .box{flex:1;min-height:22px}.patch{padding:2px 8px;border:1px dashed var(--accent);border-radius:6px;color:var(--accent)}
.configured{display:grid;grid-template-columns:1fr 16px 1.45fr;grid-template-rows:1fr 20px;gap:4px}.configured .event{height:100%}.configured>.arrow{grid-column:2}.hook-list{display:flex;flex-direction:column;gap:4px;height:100%}.hook-list .box{flex:1}.hook-result{grid-column:1/4;text-align:center;color:var(--muted)}
.parallel{flex-direction:column;gap:5px}.lane{display:flex;align-items:center;gap:4px;width:100%;flex:1}.lane>span:first-child{width:28px;color:var(--muted)}.lane .box{width:58px}.run{flex:1;height:4px;border-radius:3px;background:linear-gradient(90deg,var(--accent),var(--line));animation:run 1.2s linear infinite}@keyframes run{50%{background-position:100px 0}}.join{color:var(--accent);min-height:15px}
.transfer{gap:4px}.tray{display:flex;flex-direction:column;align-items:stretch;gap:3px;flex:1;height:100%;min-width:0}.tray b{text-align:center}.tray .box{flex:1;min-height:0}.tray .empty{flex:1;text-align:center;padding-top:5px}.transfer-arrow{flex:none;text-align:center;color:var(--accent)}
.compare{display:grid;grid-template-columns:1fr 16px 1fr;grid-template-rows:1fr 21px;gap:3px}.pane{display:flex;flex-direction:column;gap:3px;padding:4px;border:1px solid var(--line);border-radius:6px;min-width:0;background:var(--bg);font-weight:700;color:var(--muted)}.pane .box{min-height:0;flex:1}.pane code{font:500 12px/1.2 ui-monospace,monospace;color:var(--fg);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.pane .changed{color:var(--accent)}.compare-arrow{align-self:center;text-align:center;color:var(--accent)}.status{grid-column:1/4;text-align:center;color:var(--muted)}
.staging{gap:3px}.bucket{display:flex;flex-direction:column;gap:3px;align-items:stretch;justify-content:flex-start;flex:1;height:calc(100% - 4px);min-width:0;text-align:center}.bucket .box{flex:1;min-height:0}.bucket .empty{flex:1}
.object{gap:5px}.object-fields{display:grid;grid-template-columns:1fr 1fr;gap:4px;flex:1;height:100%}.object-fields .box:last-child{grid-column:1/3}.object .object-id{width:34%;height:100%;font-family:ui-monospace,monospace;font-size:12px}
.pointer,.references,.revert,.graph,.pr-review,.queue,.conflict{flex-direction:column}.pointer-label{border:1px solid var(--accent);border-radius:6px;padding:2px 10px;color:var(--accent)}.commits,.reference-row,.graph-row,.review-steps,.queue-base,.queue-checks,.result,.sides,.state-line{display:flex;align-items:center;justify-content:center;gap:3px;width:100%;flex:1;min-height:0}.commits .box,.reference-row .box,.graph-row .box,.review-steps .box,.queue-base .box,.queue-checks .box,.result .box,.sides .box{flex:1;min-height:22px}.pointer-note{color:var(--muted)}.references{gap:4px}.reference-row{width:100%;padding:2px}.reference-row.detached{border:1px dashed var(--accent);border-radius:6px}.reference-row>span:last-child:not(.box){color:var(--accent)}
.graph{gap:2px}.graph-row b{width:45px;flex:none}.graph-row>span:last-child:not(.box){color:var(--muted)}.replay-arrow{color:var(--accent);line-height:1}.cherry .graph-row .box{flex:1}.revert .state-line{border-top:1px dashed var(--line);color:var(--muted)}.state-line strong{font-weight:600;padding:2px 5px;border-radius:5px}
.conflict{gap:1px}.conflict .sides{flex:1}.conflict-down{color:var(--accent);height:17px}.conflict .result{flex:1}
.pr-review{gap:5px}.diff-card{width:100%;flex:1;min-height:0;padding:4px 8px;border:1px solid var(--line);border-radius:6px;background:var(--bg);display:flex;align-items:center;justify-content:space-between;gap:5px}.diff-card code{font:500 12px ui-monospace,monospace;color:var(--accent)}.review-steps{flex:1;gap:1px}.review-steps .box{padding:3px 1px}.review-steps .arrow{font-size:12px}
.queue{gap:4px}.queue-base,.queue-checks{flex:1}.queue-checks{padding-left:20%;padding-right:4%}.fallback{gap:4px}.fallback .box{flex:1}
.midx,.pickaxe,.hashes,.branch-cleanup{position:relative;flex-direction:column;gap:3px}.midx-row,.cleanup-row{display:flex;align-items:center;gap:4px;width:100%;flex:1;min-height:0}.midx-row b{width:57px;flex:none}.midx-row .box{flex:1;height:100%;min-height:0}.midx-row span:last-child:not(.box){flex:1;color:var(--muted);text-align:center}.midx-old{background:color-mix(in srgb,var(--accent-2) 18%,var(--surface))}.midx-combined{border-style:dashed}
.pickaxe{display:grid;grid-template-columns:1.2fr 1fr;grid-template-rows:1fr 23px;gap:4px}.pickaxe-code,.pickaxe-log{display:flex;flex-direction:column;gap:3px;min-width:0;height:100%;padding:4px;border:1px solid var(--line);border-radius:7px;background:var(--bg)}.pickaxe-code code{font:500 12px/1.2 ui-monospace,monospace;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.pickaxe-code code:first-of-type{color:var(--accent)}.pickaxe-log .box{flex:1;min-height:0}.pickaxe-match{border-style:dashed}.pickaxe-filter{grid-column:1/3;text-align:center;color:var(--accent);padding:2px}
.hashes{flex-direction:row;flex-wrap:wrap;align-content:center}.hash-lane{display:flex;flex-direction:column;justify-content:center;gap:5px;width:37%;min-width:0;height:62%;padding:4px;border:1px solid var(--line);border-radius:7px;background:var(--bg);text-align:center}.hash-lane .box{font:500 12px/1.2 ui-monospace,monospace;min-height:32px}.hash-bridge{width:22%;text-align:center;border-bottom:2px dashed var(--accent);color:var(--muted);font-size:12px}.hash-note{width:100%;text-align:center;color:var(--muted)}
.cleanup-row b{width:53px;flex:none}.cleanup-row>span:not(.box){flex:1;min-width:0;text-align:center;color:var(--muted)}.cleanup-row .box{width:36%;height:100%;min-height:0}.cleanup-preview{width:100%;text-align:center;color:var(--accent);min-height:18px}
.reset-grid{display:flex;flex-direction:column;gap:2px}.reset-head,.reset-row{width:100%;display:grid;grid-template-columns:48px repeat(3,1fr);gap:3px;text-align:center}.reset-head b{width:auto}.reset-row{flex:1;align-items:center;border:1px solid var(--line);border-radius:5px;background:var(--bg)}.reset-row strong{font-weight:600}.reset-row .changed{color:var(--accent)}.reset-row.active{border-color:var(--accent);background:color-mix(in srgb,var(--accent) 14%,var(--surface))}
.stash-shelf{position:relative;gap:5px}.stash-zone{flex:1;align-self:flex-start;min-width:0;height:calc(100% - 23px);display:flex;flex-direction:column;align-items:stretch;justify-content:center;gap:4px;padding:4px;border:1px solid var(--line);border-radius:7px;background:var(--bg);text-align:center}.stash-zone .box{flex:1;min-height:0}.stash-zone .box:not(.active){opacity:.7}.stash-transfer{flex:none;width:48px;text-align:center;color:var(--accent)}.stash-floor{position:absolute;bottom:0;width:100%;text-align:center;color:var(--muted);font-size:12px}
.tracking{flex-direction:column;gap:3px}.tracking-lane{display:flex;align-items:center;gap:4px;width:100%;flex:1;min-height:0}.tracking-lane b{width:52px;flex:none}.tracking-lane .box{width:17%;height:100%;min-height:0}.tracking-lane>span:last-child:not(.box){margin-left:auto;color:var(--muted)}.tracking-note{width:100%;text-align:center;color:var(--accent);min-height:16px}
.bisect-timeline{flex-direction:column;gap:3px}.bisect-ends,.bisect-window{display:flex;justify-content:space-between;width:100%;color:var(--muted)}.bisect-commits{display:flex;align-items:center;justify-content:space-between;gap:2px;width:100%;flex:1}.bisect-commits .box{flex:0 0 clamp(27px,8vmin,43px);min-width:0;min-height:clamp(27px,8vmin,43px);border-radius:50%}.bisect-window{justify-content:center;gap:5px}.bisect-window span{border:1px solid var(--line);border-radius:5px;padding:2px 4px;font-size:12px}.bisect-window span.active{color:var(--accent);border-color:var(--accent)}
@media(max-width:350px){.demo{padding:8px}.diagram{font-size:12px}.folder{gap:2px}.folder small{display:none}.arrow{font-size:15px}.graph-row b{width:38px}.diff-card{padding:3px 5px}}

const moments=[{"focus":0,"label":"All layers start from main"},{"focus":1,"label":"A targets main"},{"focus":2,"label":"B targets A, not main"},{"focus":3,"label":"C targets B; merge from below"}];let n=0;const cues=[...document.querySelectorAll('[data-cue]')],ticks=[...document.querySelectorAll('.ticks i')],caption=document.getElementById('caption'),dynamic=document.querySelector('.dynamic');function show(){const m=moments[n];cues.forEach(el=>el.classList.toggle('active',el.dataset.cue.split(',').includes(String(m.focus))));if(dynamic&&m.cells)dynamic.textContent=m.cells[m.cells.length-1];ticks.forEach((el,i)=>el.classList.toggle('active',i===n));caption.textContent=m.label;n=(n+1)%moments.length}show();let timer=setInterval(show,1050);document.querySelector('.demo').addEventListener('pointerdown',()=>{clearInterval(timer);show()})