:root{--bg:#E7EAEC;--surface:#F5F6F7;--ink:#15202A;--muted:#56626D;--line:#C8CFD5;--metal:#AEB7BF;--metal-2:#8C979F;--metal-dark:#5E6A74;--bore:#D5DADE;--air:#2E7BD6;--air-deep:#1B55A3;--fire:#FF6A13;--exhaust:#838A91;--ok:#1E8A5A;--bad:#C23B2B;--stroke:var(--air);box-sizing:border-box;padding-top:env(safe-area-inset-top,0px);padding-bottom:env(safe-area-inset-bottom,0px)}@media(prefers-color-scheme:dark){:root:not([data-theme=light]){--bg:#14181B;--surface:#1C2226;--ink:#E6EAED;--muted:#9AA5AE;--line:#2E363C;--metal:#58636C;--metal-2:#6B7780;--metal-dark:#87939C;--bore:#252C31;--air:#4C95EA;--air-deep:#2F6FC4;--fire:#FF7A2B;--exhaust:#8E959C;--ok:#3DB37E;--bad:#E0604F}}*,*:before,*:after{box-sizing:inherit}html{scroll-padding-top:env(safe-area-inset-top,0px)}body{margin:0;background:var(--bg);color:var(--ink);font-family:Readex Pro,system-ui,Segoe UI,Tahoma,sans-serif;font-weight:300;line-height:1.55;-webkit-font-smoothing:antialiased}.wrap{max-width:1100px;margin:0 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var(--line);border-radius:20px;padding:16px}.now{display:flex;justify-content:space-between;align-items:baseline;gap:8px;padding:2px 4px 6px}.now-name{font-size:1.7rem;font-weight:600;color:var(--stroke);transition:color .25s}.now-meta{color:var(--muted);font-size:.85rem;text-align:end}svg.engine{display:block;width:100%;height:auto;max-height:56vh;margin:0 auto;touch-action:manipulation}.controls{display:flex;flex-wrap:wrap;align-items:center;gap:10px;margin-top:10px}.controls .btn{min-width:88px;padding:10px 18px}.speed{display:flex;align-items:center;gap:8px;flex:1;min-width:160px;color:var(--muted);font-size:.85rem}.speed input{flex:1;accent-color:var(--ink)}ol.track{list-style:none;padding:0;margin:14px 0 0;display:grid;grid-template-columns:repeat(4,1fr);gap:6px}ol.track button{width:100%;background:none;border:none;border-top:4px solid var(--line);padding:8px 2px 0;text-align:start;color:var(--muted);font-size:.8rem;line-height:1.25}ol.track button 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0;font-size:.92rem}.msg.err{color:var(--bad)}.msg.ok{color:var(--ok)}.linkbtn{background:none;border:none;padding:0;color:var(--muted);text-decoration:underline;font-size:.88rem;margin-top:14px}.metal{fill:var(--metal)}.metal2{fill:var(--metal-2)}.mdark{fill:var(--metal-dark)}.bore{fill:var(--bore)}.edge{stroke:var(--metal-dark);stroke-width:1}.g-air{fill:var(--air)}.g-deep{fill:var(--air-deep)}.g-fire{fill:var(--fire)}.g-exh{fill:var(--exhaust)}.port-in{fill:var(--air)}.port-ex{fill:var(--exhaust)}.ceramic{fill:#f2f2ee;stroke:var(--metal-dark);stroke-width:1}.part{cursor:pointer;transition:opacity .2s}.has-sel .part:not(.sel){opacity:.35}.part.sel .body{stroke:var(--ink);stroke-width:2.5}#rod.sel line{stroke:var(--ink)}.part:focus{outline:none}.part:focus-visible .body{stroke:var(--air);stroke-width:3}[hidden]{display:none!important}.seg{display:inline-flex;border:1px solid var(--line);border-radius:999px;padding:3px;margin:2px 0 10px;gap:2px}.seg button{border:none;background:none;border-radius:999px;padding:6px 16px;font-weight:500;color:var(--muted)}.seg button[aria-pressed=true]{background:var(--ink);color:var(--surface)}.seg button[disabled]{opacity:.4;cursor:default}.stage3d{position:relative;width:100%;height:min(58vh,540px);min-height:320px;touch-action:none;cursor:grab;border-radius:14px;overflow:hidden;background:radial-gradient(ellipse at 50% 38%,var(--surface),var(--bg))}.stage3d:active{cursor:grabbing}.stage3d canvas{display:block;width:100%;height:100%}.loading3d{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;margin:0;padding:20px;text-align:center;color:var(--muted)}.tools3d{display:flex;flex-wrap:wrap;gap:8px;margin-top:10px}.btn.sm{padding:7px 14px;font-size:.9rem;min-width:0}.hint3d{font-size:.82rem;margin:8px 2px 0}.label3d{position:absolute;transform:translate(-50%,-140%);background:var(--ink);color:var(--surface);padding:4px 12px;border-radius:999px;font-size:.8rem;font-weight:500;pointer-events:none;white-space:nowrap;box-shadow:0 4px 14px #0000002e}.mod small.count{display:block;margin-top:3px;font-size:.78rem}.mod .num{min-width:2.1em}@media(prefers-reduced-motion:reduce){*{transition:none!important}}