.stack{--surface: #fffdfb;padding-bottom:72px}.stack [hidden]{display:none!important}.controls{display:flex;align-items:center;gap:14px;flex-wrap:wrap;padding:14px 0 18px;border-bottom:1px solid var(--hairline)}.is-tracing .controls{position:sticky;top:0;z-index:2;background:var(--bg)}.controls__go{appearance:none;border:0;cursor:pointer;height:36px;padding:0 16px;border-radius:6px;background:#ce5517;color:#fff;font-family:var(--font-sans);font-size:14px;font-weight:500}.controls__go:hover{background:#b84a0f}.controls__go:disabled{background:var(--dot);cursor:default}.controls__stop{appearance:none;border:0;background:none;cursor:pointer;height:36px;padding:0 6px;font-family:var(--font-sans);font-size:14px;font-weight:500;color:var(--muted)}.controls__stop:hover{color:var(--accent)}.controls__caption{margin:0;flex:1 1 320px;min-width:0;display:flex;gap:12px;align-items:baseline;font-size:15px;line-height:1.5}.controls__step{font-family:var(--font-mono);font-size:12px;font-weight:500;letter-spacing:.08em;color:var(--faint);white-space:nowrap}.controls__step:empty{display:none}.layer{display:grid;grid-template-columns:208px minmax(0,1fr);column-gap:40px;padding:40px 0;border-bottom:1px solid var(--hairline);animation:rise .52s ease both;animation-delay:calc(var(--i) * 90ms)}.layer:last-child{border-bottom:0}@keyframes rise{0%{opacity:0;transform:translateY(10px)}}.rail{display:flex;flex-direction:column;gap:6px}.rail__number{font-family:var(--font-mono);font-size:12px;font-weight:500;letter-spacing:.14em;color:var(--accent)}.rail__name{margin:2px 0 0;font-size:22px;line-height:1.2;font-weight:700;letter-spacing:-.01em}.rail__tagline{margin:0;font-family:var(--font-serif);font-style:italic;font-size:17px;line-height:1.4;color:var(--muted)}.rail__description{margin:8px 0 0;font-size:14px;line-height:1.6;color:var(--muted)}.plane{min-width:0}.micro{font-family:var(--font-mono);font-size:11px;font-weight:500;letter-spacing:.1em;text-transform:uppercase;color:var(--faint)}.micro--accent{color:var(--accent)}.node{display:inline-block;border:1px solid var(--hairline);border-radius:6px;padding:7px 10px;font-family:var(--font-mono);font-size:11px;line-height:1;font-weight:500;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);background:var(--surface);white-space:nowrap}.node--control{border-color:var(--ink);background:var(--ink);color:#f4ede6}.cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:12px}.card{border:1px solid var(--hairline);border-radius:8px;padding:14px 16px 16px;background:var(--surface)}.card__name{margin-top:6px;font-size:15px;font-weight:600;line-height:1.3}.card__detail{margin:6px 0 0;font-size:13px;line-height:1.55;color:var(--muted)}.zone{border:1px dashed var(--dot);border-radius:8px;padding:14px 16px 16px}.solid{border:1px solid var(--hairline);border-radius:8px;padding:14px 16px 16px;background:var(--surface)}.box__name{margin-top:6px;font-size:15px;font-weight:600;line-height:1.3}.box__members{margin-top:4px;font-size:13px;line-height:1.5}.box__detail{margin:6px 0 0;font-size:13px;line-height:1.55;color:var(--muted)}.merge,.down{position:relative}.merge>div,.down:before{position:absolute;background:var(--dot)}.merge__stub{top:0;height:50%;width:1px}.merge__stub--left{left:calc(25% - 3px)}.merge__stub--right{left:calc(75% + 3px)}.merge__bar{left:calc(25% - 3px);right:calc(25% - 3px);top:50%;height:1px}.merge__trunk{left:50%;top:50%;bottom:0;width:1px}.down:before{content:"";left:50%;top:0;bottom:0;width:1px}.rail,[data-id]{transition:opacity .24s ease,border-color .24s ease,background-color .24s ease,box-shadow .24s ease}[data-id]{scroll-margin-top:88px}.is-tracing .layer:not(.is-lit) .rail{opacity:.4}.is-tracing [data-id]:not(.is-lit){opacity:.3}.card.is-lit,.zone.is-lit,.solid.is-lit{border-color:var(--accent);border-style:solid;background:var(--tint);box-shadow:0 0 0 3px #bf4a1024}@media(max-width:720px){.layer{grid-template-columns:minmax(0,1fr);row-gap:20px;padding:32px 0}}@media(prefers-reduced-motion:reduce){.layer{animation:none}.rail,[data-id]{transition:none}}