:root{--mux-blue:#1675d1;--mux-green:#078e60;--mux-red:#e43a2f;--mux-black:#111617}
.mux-hero svg{width:100%;height:100%}.hero-stream,.hero-select{fill:none;stroke:#5be4d0;stroke-width:5;stroke-linecap:round;stroke-linejoin:round}.hero-stream{fill:#142a47aa}.hero-select{stroke:#ffd36a}.route-dot{fill:#fff;filter:drop-shadow(0 0 6px #61ffe4)}
.lab4-circuits{grid-template-columns:1fr!important}.gate-choice{gap:10px}.mini-route{display:grid;place-items:center;min-width:42px;height:28px;border:2px solid currentColor;border-radius:7px;font-weight:900}.gate-choice.coming-soon{opacity:.58}.gate-choice small{margin-left:auto}
.mux-board{width:min(100%,610px);aspect-ratio:2/3}.mux-board #placed-layers,.mux-board .mux-layer{position:absolute;inset:0;width:100%;height:100%;pointer-events:none}.mux-board #placed-layers{z-index:2}.mux-chip{position:absolute;z-index:2;filter:drop-shadow(2px 5px 4px rgba(0,0,0,.32));overflow:visible}.mux-chip-name{position:absolute;z-index:7;transform:translateX(-50%);padding:3px 8px;border:1px solid #b4c8d8;border-radius:6px;background:#f8fbff;color:#18304a;font:700 clamp(7px,.85vw,10px)/1 Arial,sans-serif;box-shadow:0 1px 3px #0002}.chip-symbol .gate-fill{fill:#dff5fb}.chip-symbol{vector-effect:non-scaling-stroke}
.mux-wire-shadow,.mux-wire-sheath,.mux-wire-highlight,.mux-metal,.mux-metal-highlight{fill:none;stroke-linecap:round;stroke-linejoin:round}.mux-wire-shadow{stroke:rgba(0,0,0,.28);stroke-width:12;transform:translate(1.4px,2px)}.mux-wire-sheath{stroke-width:8}.mux-wire-highlight{stroke:rgba(255,255,255,.32);stroke-width:1.6;transform:translate(-.8px,-1px)}.mux-metal{stroke:#aeb2b0;stroke-width:4;filter:drop-shadow(.7px 1px .45px rgba(45,49,48,.42))}.mux-metal-highlight{stroke:rgba(255,255,255,.78);stroke-width:.8;transform:translate(-.35px,-.6px)}
.mux-wire.green .mux-wire-sheath{stroke:#078e60}.mux-wire.blue .mux-wire-sheath{stroke:#1675d1}.mux-wire.red .mux-wire-sheath{stroke:#e43a2f}.mux-wire.black .mux-wire-sheath{stroke:#111617}
.mux-wire.green .mux-wire-shadow{stroke-width:7.2}.mux-wire.green .mux-wire-sheath{stroke-width:4.8}.mux-wire.green .mux-wire-highlight{stroke-width:.96}.mux-wire.green .mux-metal{stroke-width:2}.mux-wire.green .mux-metal-highlight{stroke-width:.4}
.mux-board .mux-wire.black{z-index:3}.mux-board .mux-wire.green{z-index:5}
.mux-label{position:absolute;z-index:8;color:#0d1418;text-shadow:0 1px 2px #fff,0 0 5px #fff;font:500 clamp(8px,1.05vw,13px)/1 Arial,sans-serif;pointer-events:none}.mux-label.strong{font-weight:700}
.mux-led{position:absolute;z-index:6;width:15%;height:11%;background:transparent;filter:drop-shadow(1px 3px 2px rgba(0,0,0,.24));pointer-events:none}.mux-led>img{position:absolute;inset:0;width:100%;height:100%;object-fit:fill;background:transparent}.mux-led[data-state="off"]{filter:grayscale(.35) brightness(.85)}
.m-led-s .led-image-main{clip-path:polygon(0 0,100% 0,100% 100%,88% 100%,88% 70.3%,0 70.3%)}
.m-led-i0 .led-image-main{clip-path:polygon(0 0,100% 0,100% 100%,88% 100%,88% 50%,0 50%)}
.m-led-i1 .led-image-main{clip-path:polygon(0 0,100% 0,100% 100%,88% 100%,88% 50%,0 50%)}
.m-led-y .led-image-main{clip-path:polygon(0 0,100% 0,100% 100%,88% 100%,88% 72.8%,0 72.8%)}
.demux-led .led-image-main{clip-path:polygon(0 0,100% 0,100% 100%,88% 100%,88% 50%,0 50%)}
.demux-led.d-led-y1 .led-image-main{clip-path:polygon(0 0,100% 0,100% 74.55%,88% 74.55%,88% 50%,0 50%)}
.demux-output-label{position:absolute;z-index:10;left:98%;color:#0d1418;text-shadow:0 1px 2px #fff,0 0 5px #fff;font:700 clamp(8px,1.05vw,13px)/1 Arial,sans-serif;white-space:nowrap}.d-led-y0 .demux-output-label{top:105%}.d-led-y1 .demux-output-label{top:74%}
.led-straight-return,.led-right-extension{position:absolute;z-index:7;inset:0;width:100%;height:100%;overflow:visible}.led-straight-return path,.led-right-extension path{fill:none;stroke-linecap:round;stroke-linejoin:round}.led-leg-shadow{stroke:rgba(0,0,0,.32);stroke-width:19;transform:translate(2px,3px)}.led-leg-wire{stroke:#090b0b;stroke-width:15}.led-leg-highlight{stroke:rgba(255,255,255,.22);stroke-width:2.5}.led-return-metal{stroke:#aeb2b0;stroke-width:8;filter:drop-shadow(.7px 1px .45px rgba(45,49,48,.42))}.led-return-metal-highlight{stroke:rgba(255,255,255,.78);stroke-width:1.4}.led-right-metal-shadow{stroke:rgba(0,0,0,.24);stroke-width:10;transform:translate(1px,1px)}.led-right-metal{stroke:#aaa9a2;stroke-width:8}.led-right-metal-highlight{stroke:rgba(255,255,255,.72);stroke-width:1.3}
.board-target{border-radius:7px}.part.placed{background:transparent!important;border-color:#bfd0dc;color:transparent;box-shadow:none}.part.placed .part-picture,.part.placed span{visibility:hidden}.part.selected{outline:3px solid #2b91ff;background:#e9f6ff}.wire-part.green:before{background:#078e60}.wire-part.blue:before{background:#1675d1}
.led-real-part{display:block;width:42px;height:46px;object-fit:contain;object-position:center;background:transparent;filter:drop-shadow(1px 2px 1px rgba(0,0,0,.22))}
.equation-cards{display:grid;gap:10px;margin:18px 0}.equation-cards span{padding:14px;border-radius:10px;background:#edf5fc;font-weight:800}.practice-feedback.correct{background:#e5f8f1;color:#087052}.practice-feedback.wrong{background:#fff0ee;color:#942e27}.answer:disabled{cursor:default;opacity:.72}
.chip-key{margin:10px 0 0;padding:10px 12px;border-radius:10px;background:#eef6fb;color:#37536a;font-size:.78rem}.chip-key strong{color:#122b43}
.mux-test-layout{grid-template-columns:.82fr 1.05fr 1fr}.large-mux{height:190px;margin:18px auto;padding:10px;border:1px solid #b8cbe2;border-radius:14px;background:#f8fbff}.large-mux svg{width:100%;height:100%}.large-mux .diagram-stroke{fill:rgba(10,134,184,.11);stroke:#0878a9;stroke-width:4;stroke-linecap:round;stroke-linejoin:round}.large-mux text{fill:#102746;font:800 14px Arial}.large-mux .mux-block-label{fill:#0878a9;font-size:20px;letter-spacing:.03em}.mux-switches{grid-template-columns:repeat(3,1fr)}.truth-scroll{overflow:auto}.test-mux-board{width:min(100%,330px)!important}.test-placed-layers{position:absolute;inset:0;pointer-events:none}.test-mux-board .test-led-off .led-image-main{filter:grayscale(1) brightness(.45);opacity:.68}.test-mux-board .test-led-on .led-image-main{filter:saturate(1.7) brightness(1.2) drop-shadow(0 0 10px rgba(60,255,75,.9));opacity:1}
.inspect-only{background:#eef4f9}.inspect-only .hero,.inspect-only .phase-nav,.inspect-only .section-title,.inspect-only .component-tray,.inspect-only .tutor,.inspect-only footer{display:none!important}.inspect-only main{max-width:850px;padding:12px;margin:auto}.inspect-only #build{display:block!important}.inspect-only .build-layout,.inspect-only .build-station{display:block}.inspect-only .bench{padding:12px}.inspect-only .board-caption span{display:none}.inspect-only .mux-board{width:min(100%,425px)}
@media(max-width:1100px){.mux-test-layout{grid-template-columns:1fr}}@media(max-width:760px){.mux-board{width:min(100%,560px)}}