:root{color-scheme:light;--ink:#172033;--muted:#60708a;--line:#d9e1ec;--paper:#fff;--bg:#f5f7fa;--blue:#256fd5;--blue-soft:#edf4ff;--green:#15785a;--green-soft:#e8f6f0;--red:#b63c4e;--navy:#14243d}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.55 Inter,ui-sans-serif,system-ui,-apple-system,"Segoe UI",sans-serif}button,input,select{font:inherit}button{touch-action:manipulation}button:focus-visible,input:focus-visible,select:focus-visible,a:focus-visible{outline:3px solid #86b7f5;outline-offset:2px}
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.nl-nav{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;margin-bottom:18px}.nl-nav button{display:grid;grid-template-columns:31px 1fr;align-items:center;gap:9px;min-height:50px;padding:8px 11px;border:1px solid var(--line);border-radius:11px;background:var(--paper);color:var(--ink);text-align:left;cursor:pointer}.nl-nav button span{width:29px;height:29px;display:grid;place-items:center;border-radius:8px;background:#edf1f6;font-size:.75rem;font-weight:850}.nl-nav button strong{font-size:.82rem}.nl-nav button.active{border-color:#80aae3;background:var(--blue-soft)}.nl-nav button.active span{background:var(--blue);color:#fff}.nl-nav button.done span{background:var(--green);color:#fff}
.nl-station{padding:clamp(20px,4vw,38px);border:1px solid var(--line);border-radius:18px;background:var(--paper)}.nl-station-head{display:grid;grid-template-columns:minmax(0,1.3fr) minmax(280px,.7fr);gap:35px;padding-bottom:28px;border-bottom:1px solid var(--line)}.nl-station-head h2{margin:5px 0 8px;font-size:clamp(1.8rem,4vw,2.8rem);letter-spacing:-.04em}.nl-station-head p{margin:0;color:var(--muted);font-size:1.02rem}.nl-station-head aside{padding:16px 18px;border-radius:13px;background:#f4f6f9}.nl-station-head aside strong{font-size:.84rem}.nl-station-head ul{margin:8px 0 0;padding-left:19px;color:#506079;font-size:.82rem}.nl-station-head li+li{margin-top:4px}
.nl-tool{margin-top:24px;padding:22px;border:1px solid var(--line);border-radius:15px;background:#fafbfd}.nl-tool-head{display:flex;justify-content:space-between;align-items:flex-start;gap:16px;margin-bottom:17px}.nl-tool-head h3,.nl-question h3,.nl-sub-step h3{margin:3px 0 2px;font-size:1.25rem}.nl-tool-head p,.nl-sub-step p{margin:0;color:var(--muted)}.nl-button{min-height:42px;padding:8px 15px;border:1px solid var(--blue);border-radius:9px;background:var(--blue);color:#fff;font-weight:800;cursor:pointer}.nl-button.secondary{border-color:#bccbde;background:#fff;color:#304967}.nl-button:hover{filter:brightness(.96)}.nl-feedback{min-height:25px;margin:14px 0 0;color:var(--muted);font-size:.88rem}.nl-feedback.good,.good{color:var(--green)!important;font-weight:750}.nl-success{display:grid;grid-template-columns:44px 1fr auto;align-items:center;gap:13px;margin-top:20px;padding:13px;border:1px solid #9bcdbb;border-radius:13px;background:var(--green-soft)}.nl-success>span{width:42px;height:42px;display:grid;place-items:center;border-radius:10px;background:var(--green);color:white;font-weight:900}.nl-success strong,.nl-success p{display:block;margin:0}.nl-success p{color:#45665b;font-size:.82rem}
.nl-card-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-top:24px}.nl-info-card{display:grid;grid-template-columns:48px 1fr;gap:11px;padding:14px;border:1px solid var(--line);border-radius:13px}.nl-hardware-icon{display:block;width:100%;height:100%;object-fit:contain}.nl-icon-box{width:44px;height:44px;display:grid;place-items:center;flex:none;padding:4px;border-radius:10px;background:var(--blue-soft)}.nl-info-card h3{margin:0;font-size:.95rem}.nl-info-card p{margin:3px 0 0;color:var(--muted);font-size:.78rem}.nl-toolbox{display:flex;flex-wrap:wrap;gap:8px;min-height:66px;padding:10px;border:1px dashed #aebdd0;border-radius:11px;background:#fff}.nl-toolbox>p{margin:auto;color:var(--muted);font-size:.85rem}.nl-token{display:flex;align-items:center;gap:8px;padding:6px 10px;border:1px solid #c4d0df;border-radius:10px;background:#fff;color:var(--ink);font-size:.8rem;font-weight:750;cursor:grab}.nl-token .nl-icon-box{width:34px;height:34px;padding:3px;border-radius:8px}.nl-token.selected{border-color:var(--blue);background:var(--blue-soft)}.nl-slots{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:9px;margin-top:13px}.nl-slot{min-height:105px;display:grid;place-items:center;align-content:center;gap:5px;padding:10px;border:2px dashed #afbed0;border-radius:12px;background:#fff;color:#4e5f77;cursor:pointer}.nl-slot small{font-size:.71rem;text-align:center}.nl-slot.filled{border-style:solid;border-color:#70b99d;background:var(--green-soft);color:var(--ink)}.nl-slot.filled .nl-icon-box{background:#fff}
.nl-hop-nav{display:grid;grid-template-columns:repeat(4,1fr);gap:7px}.nl-hop-nav button{display:grid;grid-template-columns:27px 1fr;align-items:center;gap:7px;padding:8px;border:1px solid var(--line);border-radius:9px;background:#fff;text-align:left;cursor:pointer}.nl-hop-nav button>span{font-size:.76rem;font-weight:750}.nl-hop-nav button.active{border-color:var(--blue);background:var(--blue-soft)}.nl-address-panel{display:grid;grid-template-columns:repeat(5,1fr);gap:8px;margin-top:15px}.nl-address-panel>div{min-width:0;padding:11px;border:1px solid var(--line);border-radius:10px;background:#fff}.nl-address-panel span,.nl-address-panel code{display:block}.nl-address-panel span{color:var(--muted);font-size:.7rem}.nl-address-panel code{margin-top:3px;font-size:.72rem;overflow-wrap:anywhere}.nl-note{padding:11px 13px;border-left:3px solid var(--blue);background:var(--blue-soft);color:#435774;font-size:.86rem}
.nl-question{margin-top:18px;padding-top:17px;border-top:1px solid var(--line)}.nl-choices{display:flex;flex-wrap:wrap;gap:8px;margin-top:12px}.nl-choices button,.nl-sequence-pool button{min-height:43px;padding:8px 13px;border:1px solid #bdcadb;border-radius:9px;background:#fff;color:var(--ink);font-weight:750;cursor:pointer}.nl-choices button:hover,.nl-sequence-pool button:hover{border-color:var(--blue);background:var(--blue-soft)}
.nl-encapsulation{margin:24px auto;width:min(760px,100%);padding:12px;border:2px solid #5d6b80;border-radius:13px;background:#edf0f5;text-align:center;font-weight:800}.nl-encapsulation b,.nl-encapsulation i,.nl-encapsulation em{display:block;margin:8px;padding:12px;border-radius:9px;font-style:normal}.nl-encapsulation b{background:#eaf2ff;color:#205baf}.nl-encapsulation i{background:#fff0df;color:#9a560f}.nl-encapsulation em{background:#e8f6f0;color:#17684f}.nl-layers{display:grid;gap:8px;margin-top:13px}.nl-layer{display:grid;grid-template-columns:125px minmax(180px,1fr) minmax(200px,1fr);align-items:center;gap:12px;width:100%;min-height:65px;padding:10px;border:1px solid var(--line);border-radius:11px;background:#fff;color:var(--ink);text-align:left;cursor:pointer}.nl-layer>b{font-size:.86rem}.nl-layer>small{color:var(--muted)}.nl-layer>div{display:flex;flex-wrap:wrap;gap:5px}.nl-layer span{padding:4px 8px;border-radius:7px;background:var(--blue-soft);color:#235a9c;font-size:.73rem}.nl-layer em{color:#9aa6b6;font-size:.75rem}
.nl-binary-board{margin-top:17px;padding:12px;border:1px solid var(--line);border-radius:12px;background:#fff;overflow-x:auto}.nl-binary-inner{min-width:850px}.nl-binary-row{display:grid;grid-template-columns:125px 1fr;align-items:center;gap:10px;padding:7px 0}.nl-binary-row+.nl-binary-row{border-top:1px solid #edf0f4}.nl-binary-row>label{font-size:.78rem;font-weight:800}.nl-binary-row>label small{display:block;color:var(--muted);font:400 .66rem ui-monospace,monospace}.nl-bits{display:grid;grid-template-columns:repeat(8,1fr) 9px repeat(8,1fr) 9px repeat(8,1fr) 9px repeat(8,1fr);gap:3px}.nl-bits>span{height:36px;display:grid;place-items:center;padding:0;border:1px solid #c4cfdd;border-radius:5px;background:#f0f3f7;color:#52627a;font:700 .72rem ui-monospace,monospace;transition:background .12s,border-color .12s}.nl-bits>span.on{border-color:var(--blue);background:var(--blue);color:#fff}.nl-bits.static>span.network-difference{border-color:#df8b31;background:#fff0da;color:#914b08;box-shadow:inset 0 0 0 1px #f1bd7f}.nl-bits i{width:1px}.nl-binary-row.values{padding-bottom:3px}.nl-bits.values>span{height:20px;border:0;background:transparent;color:#8b97a8;font-size:.54rem}.nl-binary-row.values>label{color:#8b97a8;font-size:.67rem}.nl-binary-row.mask{background:var(--blue-soft);margin:0 -7px;padding:9px 7px;border-radius:8px}.nl-bit-legend{display:flex;align-items:center;gap:7px;margin:8px 2px 0;color:var(--muted);font-size:.72rem}.nl-bit-legend i{width:14px;height:14px;flex:none;border:1px solid #df8b31;border-radius:4px;background:#fff0da}.nl-mask-slider{margin:13px 0 4px;padding:13px 15px;border:1px solid var(--line);border-radius:11px;background:#fff}.nl-mask-slider label{display:flex;justify-content:space-between;gap:15px;margin-bottom:8px;font-size:.78rem;font-weight:800}.nl-mask-slider output{color:var(--blue);font-weight:850}.nl-mask-slider input{width:100%;accent-color:var(--blue);cursor:pointer}.nl-mask-slider>div{display:flex;justify-content:space-between;color:var(--muted);font-size:.65rem}.nl-choices button:disabled{cursor:default;opacity:.55}
.nl-arp-visual,.nl-routing-path{display:flex;align-items:center;justify-content:center;overflow-x:auto;padding:18px 4px}.nl-arp-visual b{min-width:105px;height:88px;display:grid;place-items:center;align-content:center;gap:3px;border:1px solid var(--line);border-radius:12px;background:#fff;font-size:.7rem}.nl-arp-visual b .nl-hardware-icon{width:48px;height:48px}.nl-arp-visual b span{font-weight:800}.nl-arp-visual i{width:80px;color:var(--blue);text-align:center;font-size:.7rem;font-style:normal}.nl-routing-path>div{min-width:120px;height:82px;display:grid;place-items:center;align-content:center;border:1px solid var(--line);border-radius:12px;background:#fff;opacity:.45}.nl-routing-path>div.active{border-color:var(--blue);background:var(--blue-soft);opacity:1}.nl-routing-path>div.passed{border-color:#78bba1;background:var(--green-soft);opacity:1}.nl-routing-path>div small{color:var(--muted)}.nl-routing-path>i{width:55px;height:2px;background:#a9b8ca}
.nl-port-doors{display:grid;grid-template-columns:repeat(4,1fr);gap:9px;margin-top:24px}.nl-port-doors div{padding:15px;border:1px solid var(--line);border-radius:12px;text-align:center}.nl-port-doors b,.nl-port-doors span{display:block}.nl-port-doors b{font-size:1.25rem}.nl-port-doors span{color:var(--muted);font-size:.75rem}.nl-select-row{display:flex;align-items:end;gap:9px;margin-top:12px}.nl-select-row label{display:grid;gap:4px;color:var(--muted);font-size:.75rem}.nl-select-row select{min-width:150px;height:42px;border:1px solid #bcc9d8;border-radius:8px;background:#fff;padding:7px}
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@media(max-width:850px){.nl-title{grid-template-columns:1fr}.nl-route{display:none}.nl-station-head{grid-template-columns:1fr;gap:18px}.nl-card-grid{grid-template-columns:1fr 1fr}.nl-address-panel{grid-template-columns:1fr 1fr}.nl-layer{grid-template-columns:105px 1fr}.nl-layer>div{grid-column:1/-1}.nl-slots{grid-template-columns:1fr 1fr}}
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