:root{color-scheme:dark;font:15px/1.5 'Segoe UI',Arial,sans-serif;--bg:#0b1016;--panel:#141c26;--line:#2d3947;--text:#f3f6fa;--muted:#a4b0bd;--accent:#9bb9ff;--orange:#f2a365;color:var(--text);background:var(--bg)}*{box-sizing:border-box}body{margin:0}a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}header{height:76px;display:flex;align-items:center;gap:24px;padding:15px 26px;border-bottom:1px solid var(--line);background:var(--panel)}header img{width:130px;display:block}header strong{font-size:18px}header small{display:block;color:var(--muted);font-size:12px}nav{display:flex;gap:24px;margin-left:auto;font-size:13px}main{height:calc(100dvh - 76px);display:grid;grid-template-columns:370px 1fr}aside{padding:24px;overflow:auto;background:var(--panel);border-right:1px solid var(--line)}.eyebrow{font-size:10px;letter-spacing:.16em;color:var(--accent)}.progress{display:flex;justify-content:space-between;color:var(--muted);font-size:12px;margin-top:18px}h1{font-size:27px;line-height:1.2;letter-spacing:-.03em;margin:12px 0 16px}p{color:var(--muted);font-size:14px}button{font:inherit;color:var(--text);background:#202d3c;border:1px solid var(--line);border-radius:8px;padding:9px 12px;cursor:pointer;font-size:12px}button:hover{border-color:var(--accent)}button:focus-visible,a:focus-visible,input:focus-visible{outline:2px solid var(--accent);outline-offset:3px}button:disabled{opacity:.35;cursor:default}.actions{display:flex;gap:8px;margin-top:23px}#play{flex:1;background:#214fbb;border-color:#2e6bff}.scrub{margin:18px 0 10px}.scrub input{width:100%;accent-color:var(--accent)}.scrub span{display:block;font-size:11px;color:var(--muted);min-height:32px}.check{font-size:12px;color:var(--muted)}details{border-top:1px solid var(--line);margin-top:20px;padding-top:16px}summary{cursor:pointer;font-size:13px;font-weight:600}#steps{padding:0;list-style:none;margin:12px 0;display:grid;gap:4px}#steps button{width:100%;text-align:left;display:flex;gap:9px;border-color:transparent;background:transparent;line-height:1.4}#steps button.active{background:#233a61;border-color:var(--accent)}#steps button span{color:var(--accent);font-variant-numeric:tabular-nums}#hold{padding:12px;border:1px solid #906b3e;border-radius:8px;background:#3a2b1b;color:#ffd6a2;font-size:13px}#hardware{display:grid;gap:6px;font-size:12px}#hardware>div{background:#1b2733;border-radius:7px;padding:10px}.tool{color:var(--accent)}#parts>div{font-size:12px;padding:7px 0;border-bottom:1px solid var(--line)}.viewport{position:relative;min-width:0;background:radial-gradient(ellipse at 50% 50%,#253344,#0b1016)}#canvas{position:absolute;inset:0}canvas{display:block}.tools{position:absolute;top:16px;left:16px;right:16px;display:flex;gap:7px;flex-wrap:wrap}.tools button{background:#14202fe8}.caption{position:absolute;bottom:0;left:0;right:0;display:flex;justify-content:space-between;gap:20px;font-size:11px;padding:13px 18px;background:#0b1016e6;color:var(--muted)}#error{position:absolute;left:10%;right:10%;top:35%;padding:24px;background:var(--panel);border:1px solid var(--orange);border-radius:12px}#evidence{font-size:11px;white-space:pre-line}@media(max-width:850px){header{height:70px;padding:12px 16px;gap:14px}header img{width:95px}nav{display:none}main{height:auto;display:flex;flex-direction:column-reverse}.viewport{height:55dvh;min-height:330px}aside{border-right:0;padding:22px}.caption{font-size:9px}.tools button{font-size:10px}#steps{max-height:260px;overflow:auto}}

#parts{display:grid;gap:6px;margin-top:12px}#parts button{text-align:left;font-size:11px}
.insert-overlay{position:absolute;inset:0;pointer-events:none}.insert-marker{position:absolute;transform:translate(-50%,-50%);pointer-events:auto;font-size:10px;font-weight:700;padding:3px 5px;background:#153d76;border:1px solid #94c2ff;white-space:nowrap}.insert-marker.m3{background:#654321;border-color:#ffc786}.insert-marker.selected,.insert-location.selected{outline:2px solid white}.insert-location-list{margin-top:16px}.insert-location-list h2{font-size:14px}.insert-location-list p{font-size:11px}.insert-location{display:block;width:100%;text-align:left;margin:5px 0;font-size:11px;border-left:3px solid #94c2ff}.insert-location.m3{border-left-color:#ffc786}