:root{color-scheme:dark;--night:#102c37;--deep:#0b222c;--paper:#eee9dd;--muted:#a8bdba;--gold:#efd49a;--rule:#ede8d82e;--mint:#8dcfc1}
.footer-ad{display:flex;justify-content:center;align-items:flex-start;min-width:0;margin:0 0 28px;overflow:hidden;text-align:center}
.footer-ad-content{flex:none;width:max-content;transform-origin:top center}
*{box-sizing:border-box}body{margin:0;background:var(--night);color:var(--paper);font-family:"Hiragino Kaku Gothic ProN","Yu Gothic",Meiryo,sans-serif;-webkit-font-smoothing:antialiased}body::before{content:"";position:fixed;inset:0;pointer-events:none;opacity:.2;background-image:radial-gradient(#f6e9c52b .5px,transparent .5px);background-size:6px 6px;mask-image:linear-gradient(130deg,transparent 10%,#000 80%)}
button,input{font:inherit}button,a,input{-webkit-tap-highlight-color:transparent}button:focus-visible,a:focus-visible,input:focus-visible{outline:2px solid var(--gold);outline-offset:4px}button{cursor:pointer;border:1px solid var(--rule);background:transparent;color:var(--paper);border-radius:2px;min-height:44px}button:hover:not(:disabled){border-color:var(--gold);color:var(--gold)}button:disabled{opacity:.4;cursor:not-allowed}a{color:inherit;text-decoration:none}a:hover{color:var(--gold)}
.shell{position:relative;max-width:1540px;margin:auto;padding:0 clamp(22px,5.2vw,82px)}.topbar{height:96px;display:flex;align-items:center;justify-content:space-between;gap:20px;border-bottom:1px solid var(--rule)}.brand{display:flex;align-items:center;gap:12px;font-size:11px;letter-spacing:.12em;font-weight:700}.sun-mark{width:17px;height:17px;border:1px solid var(--gold);border-radius:50%;box-shadow:inset 0 0 0 4px var(--night);background:var(--gold);flex:none}.divider{color:var(--muted)}.edition{font:11px Georgia,serif;letter-spacing:.15em;color:var(--muted)}.edition span{color:var(--gold);margin-left:18px}
.intro{display:flex;align-items:center;gap:clamp(48px,9vw,150px);padding:53px 0 44px}.eyebrow{color:var(--gold);font:10px Georgia,serif;letter-spacing:.24em;margin:0 0 21px}.eyebrow::before{content:"";display:inline-block;vertical-align:middle;width:26px;height:1px;background:var(--gold);margin-right:13px}h1{font:clamp(76px,8.4vw,124px)/.9 Georgia,serif;letter-spacing:-.06em;margin:0}h1 span{color:var(--gold)}h2{font-size:16px;letter-spacing:.08em;font-weight:500;margin:0}.intro-copy h2{font-size:21px;letter-spacing:.14em}.intro-copy p{color:var(--muted);font-size:12px;line-height:2.2;margin:16px 0 0}
.workspace{display:grid;grid-template-columns:280px minmax(0,1fr);gap:38px;align-items:start}.controls{border-top:1px solid var(--gold);padding-top:21px}.section-heading{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:22px}.section-heading h2{font-size:14px}.section-heading>span{font:9px Georgia,serif;letter-spacing:.1em;color:var(--muted)}.help,.field small{color:var(--muted);font-size:11px;line-height:1.9}.help{margin:0 0 18px}.presets{display:grid;grid-template-columns:repeat(3,1fr);gap:6px;margin-bottom:25px}.presets button{font-size:10px;padding:8px 3px}.field{margin:0 0 23px}.field label{display:flex;justify-content:space-between;font-size:12px}.field output{color:var(--gold);font-variant-numeric:tabular-nums}.field input{display:block;width:100%;height:24px;margin:12px 0 5px;accent-color:var(--gold)}.field small{font-size:10px}.side-button,.primary{width:100%;display:flex;align-items:center;justify-content:space-between;padding:14px;font-size:12px}.side-button{margin-bottom:11px}.primary{background:var(--gold);color:var(--deep);border-color:var(--gold);font-weight:700}.primary:hover:not(:disabled){background:#ffe9b7;color:var(--deep)}.history-actions{display:flex;gap:12px;margin-top:9px}.history-actions button{flex:1;border:0;font-size:11px}.reset{border:0;border-bottom:1px solid var(--rule);font-size:11px;display:block;margin:0 auto;padding:0 4px}
.paper-panel{min-width:0;padding:24px 25px 18px;background:radial-gradient(ellipse at 50% 35%,#21485280,#0d2a3570);border:1px solid #efd49a38;box-shadow:0 22px 60px #000c111a}.paper-panel .section-heading{margin-bottom:18px}.board-toolbar{display:flex;justify-content:space-between;gap:8px;align-items:center;color:var(--muted);font-size:11px}.board-toolbar>span{color:var(--gold);font-variant-numeric:tabular-nums}.board-toolbar label{display:flex;align-items:center;gap:5px;min-height:32px;cursor:pointer}.board-toolbar input{accent-color:var(--gold);width:16px;height:16px}#board{display:block;width:100%;height:clamp(320px,36vw,500px);touch-action:none;cursor:crosshair;user-select:none;margin:10px 0 18px}.original-sheet{fill:none;stroke:#a8bdba66;stroke-width:.3;stroke-dasharray:1.5 1.5}.paper-face{stroke:#284749;stroke-width:.35;stroke-linejoin:round}.paper-face.front{fill:var(--gold)}.paper-face.back{fill:var(--paper)}.crease-line{stroke:var(--mint);stroke-width:2;stroke-dasharray:7 5;vector-effect:non-scaling-stroke;pointer-events:none}.crease-center{fill:var(--mint);stroke:var(--deep);stroke-width:.4;pointer-events:none}.legend{display:flex;gap:12px 18px;flex-wrap:wrap;color:var(--muted);font-size:10px}.legend span{display:inline-flex;align-items:center;gap:6px}.legend .front::before,.legend .back::before{content:"";width:10px;height:10px;background:var(--gold)}.legend .back::before{background:var(--paper)}.legend .line::before{content:"";width:16px;border-top:1px dashed var(--mint)}#status{font-size:12px;line-height:1.9;color:var(--gold);min-height:46px;border-top:1px solid var(--rule);padding-top:13px;margin:18px 0 0}
.notes{display:grid;grid-template-columns:280px minmax(0,1fr);gap:38px;border-top:1px solid var(--rule);padding:34px 0 40px;margin-top:42px}.notes h2{font-size:16px;line-height:1.8}.notes h3{font-size:12px;font-weight:500;color:var(--paper);margin:0 0 9px}.notes p:not(.eyebrow){font-size:12px;color:var(--muted);line-height:2.1;margin:0 0 20px}footer{display:flex;flex-wrap:wrap;gap:16px;border-top:1px solid var(--rule);padding:23px 0 28px;color:var(--muted);font-size:10px;letter-spacing:.06em}.disclaimer{flex:0 0 100%;font-size:12px;line-height:1.9}.disclaimer h2{margin:0 0 6px;color:var(--gold);font-size:12px}.disclaimer p{margin:0;overflow-wrap:anywhere}
@media(max-width:1050px){.workspace,.notes{grid-template-columns:250px minmax(0,1fr);gap:24px}.shell{padding:0 28px}.paper-panel{padding:22px 17px}.edition{font-size:9px}}
@media(max-width:760px){.shell{padding:0 22px}.topbar{height:72px}.brand{font-size:10px;gap:9px}.edition{display:none}.intro{padding:36px 0 31px;display:block}.intro-copy{margin-top:25px}.intro-copy h2{font-size:18px}.intro-copy p{margin-top:12px}.workspace{display:flex;flex-direction:column;gap:25px}.controls,.paper-panel{width:100%}.paper-panel{order:-1;padding:19px 13px 13px}#board{height:320px;max-height:85vw}.board-toolbar{font-size:10px}.controls .help br{display:none}.presets button{font-size:11px}.notes{grid-template-columns:1fr;gap:18px;margin-top:31px;padding:29px 0}.notes p:not(.eyebrow){font-size:12px}.legend{gap:10px;font-size:9px}}
select{font:inherit;background:var(--deep);color:var(--paper);border:1px solid var(--rule);border-radius:2px;min-height:44px;padding:8px;min-width:0}select:focus-visible{outline:2px solid var(--gold);outline-offset:4px}.field select{width:100%;font-size:11px;margin-top:8px}.sheet-picker{display:grid;grid-template-columns:1fr 1fr;gap:8px;align-items:center;margin-bottom:14px}.sheet-picker label{font-size:11px}.sheet-picker select{font-size:12px}.sheet-picker button{font-size:11px;padding:8px}.mode-buttons{display:flex;gap:8px;margin:10px 0}.mode-buttons button{flex:1;font-size:12px}.mode-buttons [aria-pressed="true"]{border-color:var(--gold);color:var(--gold);background:#efd49a12}.arrangement{border-top:1px solid var(--rule);padding-top:20px;margin-top:24px}.arrangement h2{font-size:14px;margin-bottom:12px}.sheet-actions{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin-top:8px}.sheet-actions button{font-size:11px}.nudge-actions{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.paper-face.front.sheet-2{fill:#8dcfc1}.paper-face.front.sheet-3{fill:#d3a6b8}.paper-face.front.sheet-4{fill:#a9b7e3}.paper-face.selected{stroke:#274e56;stroke-width:1;vector-effect:non-scaling-stroke}.paper-face:not(.selected){stroke-width:.25}.fold-hatch{pointer-events:none}#board.move-mode{cursor:grab}#board.move-mode:active{cursor:grabbing}.board-toolbar{flex-wrap:wrap}.legend .front::before{background:linear-gradient(90deg,var(--gold) 50%,var(--mint) 50%)}
@media(min-width:761px){.paper-panel{position:sticky;top:12px}}@media(max-width:380px){.history-actions{gap:4px}.history-actions button{font-size:10px}.shell{padding:0 16px}}
.snap-toolbar{display:flex;align-items:center;gap:12px;margin:12px 0}.snap-toolbar button{flex:none;padding:8px 12px;font-size:11px}.snap-toolbar [aria-pressed="true"]{border-color:var(--mint);color:var(--mint);background:#8dcfc112}.snap-toolbar p{margin:0;color:var(--muted);font-size:10px;line-height:1.8}#snap-guides{pointer-events:none;fill:none;stroke:var(--mint)}#snap-guides>*{vector-effect:non-scaling-stroke;stroke-width:1.5}#snap-guides line{stroke-dasharray:3 4}@media(max-width:380px){.snap-toolbar{align-items:flex-start;gap:8px}.snap-toolbar button{padding:8px}}
.gesture-help{font-size:11px;line-height:1.8;color:var(--mint);margin:7px 0}.crease-hit{stroke:transparent;stroke-width:28;vector-effect:non-scaling-stroke;pointer-events:stroke;cursor:move}.handle-hit{fill:transparent;pointer-events:all}.handle-dot{fill:var(--deep);stroke:var(--mint);stroke-width:2;vector-effect:non-scaling-stroke;pointer-events:none}.center-dot{fill:var(--mint)}#crease-handles [data-handle]{cursor:crosshair}#crease-handles [data-handle="slide"]{cursor:move}.crease-fine{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:0 0 18px}.crease-fine>div{display:flex;align-items:center;gap:6px}.crease-fine span{font-size:10px;color:var(--muted)}.crease-fine button{flex:1;font-size:11px;min-width:0}.crease-fine[hidden]{display:none}@media(max-width:380px){.crease-fine{gap:6px}.crease-fine>div{gap:4px}.crease-fine button{font-size:10px}}
.view3d-open{display:flex;align-items:center;justify-content:space-between;width:100%;margin-top:16px;padding:12px 16px;color:var(--mint);border-color:#8dcfc166;font-size:12px;background:#8dcfc10b}.viewer-dialog{width:min(960px,calc(100vw - 28px));max-height:calc(100dvh - 28px);padding:24px;border:1px solid #efd49a66;border-radius:4px;background:var(--night);color:var(--paper);box-shadow:0 24px 90px #0009;overflow:auto}.viewer-dialog::backdrop{background:#04171dcc;backdrop-filter:blur(4px)}.viewer-dialog[open]{display:flex;flex-direction:column;gap:12px}.viewer-heading{display:flex;align-items:center;justify-content:space-between;gap:16px}.viewer-heading .eyebrow{margin-bottom:10px}.viewer-heading h2{font-size:18px}.viewer-heading button{font-size:11px;padding:8px 14px;flex:none}.viewer-dialog .help{margin:0}.viewer-presets{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}.viewer-presets button{font-size:12px}#view3d-canvas{display:block;width:100%;height:clamp(220px,44vh,480px);flex:none;background:radial-gradient(ellipse at center,#21485280,#0b222c);border:1px solid var(--rule);border-radius:2px;touch-action:none;cursor:grab}#view3d-canvas:active{cursor:grabbing}#view3d-canvas:focus-visible{outline:2px solid var(--mint);outline-offset:2px}.viewer-options{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:16px}.viewer-zoom{display:flex;align-items:center;gap:10px;font-size:11px}.viewer-zoom button{width:44px;font-size:18px}.viewer-zoom output{min-width:40px;text-align:center;color:var(--gold)}.viewer-spread{display:flex;align-items:center;gap:10px;font-size:11px}.viewer-spread input{width:140px;accent-color:var(--mint);min-height:32px}.viewer-spread input:disabled{opacity:.4}#view3d-status{font-size:12px;line-height:1.8;color:var(--gold);margin:0}.viewer-key-help{font-size:10px}@media(max-width:600px){.viewer-dialog{padding:16px;gap:10px}.viewer-heading{align-items:flex-start;gap:8px}.viewer-heading h2{font-size:14px;line-height:1.7}.viewer-heading .eyebrow{font-size:8px}.viewer-heading button{padding:8px;font-size:10px}.viewer-options{gap:8px}.viewer-spread{width:100%}.viewer-spread input{flex:1;min-width:0}.viewer-presets{gap:6px}}

.viewer-dialog{width:min(1160px,calc(100vw - 28px))}.solid-layout{display:grid;grid-template-columns:minmax(0,1fr) 270px;gap:24px;align-items:start}.solid-stage{min-width:0;display:flex;flex-direction:column;gap:12px;position:sticky;top:0}.solid-controls{min-width:0;border-left:1px solid var(--rule);padding-left:24px}.solid-controls .field{margin-bottom:14px}.solid-controls .field input{margin:5px 0;height:30px}.solid-controls .field small{display:block}.solid-selects{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin-bottom:14px}.solid-selects label{font-size:11px;min-width:0}.solid-selects select{display:block;width:100%;margin-top:5px;font-size:11px}.solid-controls h3{font-size:14px;color:var(--gold);font-weight:500;margin:0 0 12px}.solid-controls .help{margin:12px 0}.solid-limit{border-top:1px solid var(--rule);padding-top:12px}#solid-reimport{font-size:10px;width:100%;padding:8px}.solid-controls .history-actions{gap:4px}.solid-controls .history-actions button{font-size:10px}.solid-stage #view3d-canvas{height:clamp(260px,47vh,500px)}[hidden]{display:none!important}@media(max-width:760px){.solid-layout{display:block}.solid-stage{display:contents}.solid-controls{padding:16px 0 0;border-left:0;border-top:1px solid var(--rule)}.solid-stage #view3d-canvas{height:clamp(160px,28dvh,230px);position:sticky;top:0;z-index:2;background-color:var(--night);margin:12px 0}.solid-stage .viewer-options{margin:12px 0}.solid-stage .viewer-key-help{margin:10px 0}.solid-controls .field input{height:36px}}

.crane-action{border-top:1px solid var(--rule);padding:14px 0 0;margin-top:12px}.crane-action .eyebrow{margin-bottom:8px}.crane-action h3{font-size:15px;color:var(--gold);font-weight:500;margin:0 0 8px}.crane-action .help{margin-bottom:10px}.crane-action .field{margin:12px 0}.crane-action .field input{margin-top:4px}.crane-steps{padding-left:22px;margin:0 0 22px}.crane-steps li{padding:8px 0;color:var(--muted);font-size:12px;line-height:1.7;border-bottom:1px solid var(--rule)}.crane-steps .done{color:var(--mint)}.crane-steps .next{color:var(--gold);font-weight:700}#view3d-panel{margin:12px 0}#view3d-panel #view3d-canvas{height:clamp(230px,36vh,360px);margin:10px 0}#view3d-panel .help{margin:8px 0;font-size:10px}#spatial-controls .field{margin-bottom:16px}#spatial-controls select{width:100%}#box-controls h2{margin-bottom:20px}@media(max-width:760px){.crane-action h3{font-size:14px}#view3d-panel #view3d-canvas{height:240px}.crane-steps li{padding:6px 0}}

#crane-controls .crane-action{border:0;padding:0;margin:0 0 18px}#crane-controls .crane-action .field small{font-size:10px}.in-recipe #view3d-canvas{height:clamp(260px,43vh,340px)!important}.in-recipe .viewer-spread{display:none}@media(max-width:760px){.in-recipe #view3d-canvas{height:260px!important}}

.manual-folds{border-bottom:1px solid var(--rule);margin-bottom:20px}.manual-folds select{width:100%;margin-top:8px;font-size:12px}.manual-folds .help{font-size:11px}.manual-active #view3d-canvas{height:clamp(300px,48vh,430px)!important}

.panel-selection{border:1px solid var(--rule);padding:10px;margin:0 0 12px}.panel-selection legend{font-size:12px;color:var(--muted)}#panel-faces{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));max-height:176px;overflow:auto}#panel-faces label{display:flex;align-items:center;gap:8px;min-height:44px;font-size:12px}#panel-faces input{accent-color:var(--mint);width:18px;height:18px}#panel-controls select{width:100%;margin-top:8px}#panel-controls .field{margin-bottom:16px}
.fold-shadow{fill:#071b24;stroke:none;pointer-events:none}.folding #board,.folding #view3d-canvas{pointer-events:none;cursor:wait}.folding #crease-handles,.folding #crease-hit,.folding #snap-guides{visibility:hidden}.folding #fold{opacity:1}
.view-mode{display:flex;gap:8px;margin:10px 0}.view-mode button{flex:1;min-width:0;padding:8px;font-size:11px}.view-mode [aria-pressed="true"]{border-color:var(--mint);color:var(--mint);background:#8dcfc112}

.viewer-surface{position:relative;margin:10px 0}#view3d-panel .viewer-surface #view3d-canvas{margin:0}#view3d-handles{position:absolute;inset:0;width:100%;height:100%;pointer-events:none}.folding #view3d-handles{visibility:hidden}
.paper-face{filter:url(#layer-shadow)}
.tutorial-highlight{animation:tutorial-pulse 1.5s ease-in-out infinite}
@keyframes tutorial-pulse{0%,100%{outline-offset:4px;filter:drop-shadow(0 0 2px #8dcfc144)}50%{outline-offset:9px;filter:drop-shadow(0 0 9px #8dcfc1aa)}}
.tutorial-callout{position:fixed;z-index:20;width:max-content;max-width:min(340px,calc(100vw - 24px));padding:12px 16px;border:1px solid var(--mint);border-radius:6px;background:#0b222cf5;box-shadow:0 8px 28px #0007;pointer-events:none}.tutorial-callout::before{content:"";position:absolute;top:-7px;left:50%;width:12px;height:12px;background:var(--deep);border-top:1px solid var(--mint);border-left:1px solid var(--mint);transform:rotate(45deg)}.tutorial-callout.above::before{top:auto;bottom:-7px;transform:rotate(225deg)}.tutorial-callout span{display:block;color:var(--mint);font-size:11px;line-height:1.6}.tutorial-callout p{margin:6px 0 0;color:var(--paper);font-size:13px;line-height:1.8}
@media(prefers-reduced-motion:reduce){.tutorial-highlight{animation:none}}
.folding .tutorial-callout{visibility:hidden}
.tutorial{grid-column:1 / -1;width:100%;padding:22px 24px;border:1px solid #8dcfc166;background:#0b222c;margin-bottom:2px}.tutorial-heading{display:flex;align-items:center;justify-content:space-between;gap:20px}.tutorial .eyebrow{margin-bottom:10px}.tutorial h2{font-size:17px}.tutorial h3{font-size:16px;color:var(--gold);margin:8px 0}.tutorial p:not(.eyebrow){font-size:12px;line-height:1.9;color:var(--muted);margin:12px 0 0}.tutorial button{padding:9px 14px;font-size:12px}.tutorial #tutorial-progress{color:var(--mint);font:12px Georgia,serif;letter-spacing:.12em}.tutorial #tutorial-hint{color:var(--paper)}.tutorial progress{display:block;width:100%;height:6px;margin:18px 0;accent-color:var(--mint)}.tutorial-actions{display:flex;gap:10px;flex-wrap:wrap}#tutorial-start,#tutorial-locate,#tutorial-keep{border-color:var(--mint);color:var(--mint);background:#8dcfc110}.tutorial-highlight{outline:3px solid var(--mint)!important;outline-offset:5px;box-shadow:0 0 0 8px #8dcfc126!important;scroll-margin:24px}.tutorial-active .presets{grid-template-columns:repeat(2,1fr)}.presets{grid-template-columns:repeat(2,1fr)}
@media(max-width:760px){.tutorial{order:-2;padding:18px 16px}.tutorial-heading{align-items:flex-start;flex-direction:column;gap:16px}.tutorial-heading button{width:100%}.tutorial-actions button{flex:1 1 140px}.tutorial-active .controls{order:-1}.tutorial-active .paper-panel{order:0}.tutorial-active .arrangement{display:none}}
.panel-pins { max-height: 24rem; overflow: auto; margin: 12px 0; }
.panel-pins fieldset { display: grid; grid-template-columns: repeat(3,minmax(0,1fr)); gap: 8px; border: 1px solid #688487; border-radius: 8px; padding: 10px; margin: 8px 0; }
.panel-pins label { min-width: 0; font-size: .8rem; }
.panel-pins input { width: 100%; min-width: 0; padding: 6px; }
.panel-pins button { grid-column: 1 / -1; }