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span{display:inline-flex;align-items:center;gap:5px}.bit-legend b{width:9px;height:9px;display:inline-block}.network-key{background:var(--ipv4-orange)}.host-key{background:#deded9}.bit-legend strong{margin-left:auto;color:var(--ipv4-orange);font:10px Courier New,monospace}.calculator-section{display:grid;grid-template-columns:.9fr 1.4fr;gap:80px;background:#ecece8}.calculator-panel{padding:24px;background:var(--ipv4-paper);border:1px solid var(--ipv4-line)}.calculator-panel label{display:block;margin-bottom:8px;color:#777770;font:9px Courier New,monospace;text-transform:uppercase}.calculator-input{display:flex;gap:8px}.calculator-input input{min-width:0;flex:1;padding:12px;border:1px solid var(--ipv4-line);color:var(--ipv4-ink);background:#fff;font:14px Courier New,monospace;outline-color:var(--ipv4-orange)}.calculator-input button{display:inline-flex;align-items:center;gap:7px;padding:0 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small{line-height:1.25}.binary-mask{display:flex;justify-content:space-between;gap:12px;margin-top:20px;color:#777770;font-size:10px}.binary-mask code{color:var(--ipv4-ink);font:10px Courier New,monospace}.cidr-table{margin-top:70px;border-top:1px solid var(--ipv4-line)}.cidr-table-head,.cidr-row{display:grid;grid-template-columns:.6fr 1fr .8fr 1.6fr;gap:18px;align-items:center}.cidr-table-head{padding:12px 0;color:#777770;font:9px Courier New,monospace}.cidr-row{min-height:58px;border-top:1px solid var(--ipv4-line)}.cidr-row strong{color:var(--ipv4-orange);font:18px Courier New,monospace}.cidr-row code,.cidr-row span{font:11px Courier New,monospace}.cidr-row p{margin:0;color:#777770;font-size:11px}.vlsm-section{display:grid;grid-template-columns:.8fr 1.5fr;gap:90px;background:#ecece8}.vlsm-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--ipv4-line)}.vlsm-grid article{min-height:240px;padding:20px;background:var(--ipv4-paper)}.vlsm-grid article:nth-child(2){background:#e3e3de}.vlsm-grid article:nth-child(3){color:#fff;background:var(--ipv4-orange)}.vlsm-grid article>span{display:block;margin-bottom:48px;color:var(--ipv4-orange);font:9px Courier New,monospace}.vlsm-grid article:nth-child(3)>span{color:#76250f}.vlsm-grid svg{margin-bottom:18px;color:var(--ipv4-orange)}.vlsm-grid article:nth-child(3) svg{color:#fff}.vlsm-grid h3{margin:0 0 7px;font-size:17px;letter-spacing:-.04em}.vlsm-grid p{max-width:190px;margin:0;color:#6b6b64;font-size:11px;line-height:1.4}.vlsm-grid article:nth-child(3) p{color:#76250f}.vlsm-calculator{margin-top:50px;padding:24px;background:var(--ipv4-paper);border:1px solid var(--ipv4-line)}.vlsm-inputs>label{display:block;margin-bottom:8px;color:#777770;font:9px Courier New,monospace;text-transform:uppercase}.vlsm-inputs>input{width:100%;padding:11px;border:1px solid var(--ipv4-line);color:var(--ipv4-ink);background:#fff;font:13px Courier 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1.5fr;gap:80px}.drill-panel{padding:24px;background:#ecece8;border:1px solid var(--ipv4-line)}.drill-top{display:flex;align-items:center;gap:15px;color:#777770;font:9px Courier New,monospace}.drill-top strong{color:var(--ipv4-orange);font-size:12px}.drill-top button{display:inline-flex;align-items:center;gap:6px;margin-left:auto;padding:7px 10px;border:1px solid var(--ipv4-line);color:var(--ipv4-ink);background:transparent;font-size:10px;cursor:pointer}.drill-question{margin:38px 0 24px;font-size:18px;line-height:1.2;letter-spacing:-.03em}.drill-question strong{color:var(--ipv4-orange);font-family:Courier New,monospace}.drill-fields{display:grid;grid-template-columns:1fr 1fr;gap:14px}.drill-fields label{display:flex;flex-direction:column;gap:7px;color:#777770;font:9px Courier New,monospace;text-transform:uppercase}.drill-fields input{padding:10px;border:1px solid var(--ipv4-line);color:var(--ipv4-ink);background:#fff;font:12px Courier New,monospace;outline-color:var(--ipv4-orange)}.drill-check{display:inline-flex;align-items:center;gap:7px;margin-top:22px;padding:11px 14px;color:#fff;background:var(--ipv4-orange);border:0;font-size:11px;font-weight:700;cursor:pointer}.drill-feedback{margin:15px 0 0;color:#b42318;font-size:11px}.drill-feedback.correct{color:#14783c}.ipv4-next{display:flex;align-items:end;justify-content:space-between;padding:110px clamp(28px,6vw,100px) 130px;background:var(--ipv4-orange)}.ipv4-next h2{margin-bottom:0;font-size:clamp(3rem,6vw,6.5rem)}.ipv4-button{display:inline-flex;align-items:center;gap:24px;padding:14px 17px;color:#fff!important;background:var(--ipv4-ink);font-size:11px;font-weight:600}.ipv4-button svg{transition:transform .2s ease}.ipv4-button:hover svg{transform:translate(4px)}@media(max-width:720px){.ipv4-nav{padding:0 18px}.ipv4-nav>span:nth-child(2){display:none}.ipv4-hero{display:block;padding:76px 20px 70px}.ipv4-hero h1{font-size:clamp(3.2rem,15vw,5rem)}.ipv4-hero-illustration{margin-top:45px}.ipv4-hero-illustration img{min-height:220px}.ipv4-section{padding:70px 20px}.address-parts,.calculator-section,.vlsm-section,.bit-section,.drill-section{display:block}.address-parts article{min-height:170px;border-bottom:1px solid var(--ipv4-line)}.address-parts article:last-child{border-bottom:0}.address-parts strong{margin-bottom:35px}.binary-note{display:block}.binary-note code{display:block;margin:14px 0;font-size:11px}.calculator-panel,.bit-panel,.drill-panel{margin-top:35px;padding:17px}.bit-legend strong{width:100%;margin-left:0}.calculator-input{display:block}.calculator-input button{width:100%;justify-content:center;min-height:42px;margin-top:8px}.result-summary{grid-template-columns:1fr}.result-table div{grid-template-columns:1fr 1fr}.result-table small{grid-column:1 / -1}.binary-mask{display:block}.binary-mask code{display:block;margin-top:8px}.cidr-table{overflow-x:auto}.cidr-table-head,.cidr-row{min-width:650px}.vlsm-grid{display:block;margin-top:35px}.vlsm-grid article{min-height:170px;border-bottom:1px solid var(--ipv4-line)}.vlsm-grid article:last-child{border-bottom:0}.vlsm-grid article>span{margin-bottom:25px}.vlsm-calculator{margin-top:35px;padding:17px}.vlsm-requirement{grid-template-columns:1fr 82px 28px}.vlsm-actions{display:grid;grid-template-columns:1fr}.vlsm-add,.vlsm-run{justify-content:center}.vlsm-results{overflow-x:auto}.vlsm-results-head,.vlsm-result-row{min-width:620px}.ipv4-next{display:block;padding:80px 20px 90px}.ipv4-button{margin-top:35px}}.routing-page{--routing-ink: #171717;--routing-paper: #f7f7f4;--routing-line: #d9d9d4;--routing-orange: #ff4b12;min-height:100vh;color:var(--routing-ink);background:var(--routing-paper);font-family:Arial,Helvetica,sans-serif}.routing-page,.routing-page *{box-sizing:border-box}.routing-page a{color:inherit;text-decoration:none}.routing-nav{display:flex;align-items:center;justify-content:space-between;min-height:48px;padding:0 24px;border-bottom:1px solid var(--routing-line);color:#777770;font:9px Courier New,monospace}.routing-back{display:inline-flex;align-items:center;gap:8px;color:var(--routing-ink)!important;font:600 10px Arial,sans-serif}.routing-back:hover{color:var(--routing-orange)!important}.routing-eyebrow{display:block;color:#777770;font:9px/1.2 Courier New,monospace;letter-spacing:.04em}.routing-hero{display:grid;grid-template-columns:minmax(0,1fr) minmax(320px,380px);align-items:center;max-width:1440px;margin:0 auto;padding:100px clamp(28px,5vw,80px) 90px;border-bottom:1px solid var(--routing-line)}.routing-hero h1,.routing-heading h2,.routing-next h2{margin:22px 0 26px;font-size:clamp(3.4rem,7vw,7.2rem);line-height:.88;letter-spacing:-.075em}.routing-hero h1 em,.routing-heading h2 em,.routing-next h2 em{font-style:normal;font-weight:400}.routing-hero p,.routing-heading>p{max-width:400px;color:#63635d;font-size:14px;line-height:1.4}.routing-hero-illustration{margin:0;overflow:hidden;background:transparent}.routing-hero-illustration img{display:block;width:100%;min-height:360px;object-fit:contain}.routing-section{max-width:1440px;margin:0 auto;padding:100px clamp(28px,6vw,100px);border-bottom:1px solid var(--routing-line)}.routing-concept{background:#ecece8}.routing-concept-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;margin-top:70px;background:var(--routing-line)}.routing-concept-grid article{min-height:235px;padding:22px;background:var(--routing-paper)}.routing-concept-grid article:nth-child(2){background:#e2e2dd}.routing-concept-grid article:nth-child(3){color:#fff;background:var(--routing-orange)}.routing-concept-grid article>span{display:block;margin-bottom:50px;color:var(--routing-orange);font:9px Courier New,monospace}.routing-concept-grid article:nth-child(3)>span{color:#76250f}.routing-concept-grid svg{margin-bottom:18px;color:var(--routing-orange)}.routing-concept-grid article:nth-child(3) svg{color:#fff}.routing-concept-grid h3{margin:0 0 8px;font-size:18px;letter-spacing:-.04em}.routing-concept-grid p{max-width:230px;margin:0;color:#6b6b64;font-size:11px;line-height:1.4}.routing-concept-grid article:nth-child(3) p{color:#76250f}.topology-section{display:flex;flex-direction:column;gap:36px;background:#f4f4f0}.topology-section .routing-heading>p{max-width:680px}.lab-topology-container{display:flex;flex-direction:column;border:1px solid var(--routing-line);background:var(--routing-paper);box-shadow:0 4px 20px #00000008}.lab-topo-toolbar{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:16px;padding:16px 24px;border-bottom:1px solid var(--routing-line);background:#ebebe6}.lab-topo-group{display:flex;align-items:center;gap:12px;flex-wrap:wrap}.lab-topo-label{font:700 9px Courier New,monospace;color:#777770;letter-spacing:.06em}.lab-topo-btn-group{display:inline-flex;border:1px solid var(--routing-line);background:#fff}.lab-topo-btn{padding:7px 14px;border:0;border-right:1px solid var(--routing-line);background:transparent;font:600 11px Arial,sans-serif;color:var(--routing-ink);cursor:pointer;transition:all .15s ease}.lab-topo-btn:last-child{border-right:0}.lab-topo-btn:hover:not(:disabled){background:#f0f0ec}.lab-topo-btn.is-active{background:var(--routing-ink);color:#fff}.lab-topo-btn:disabled{opacity:.5;cursor:not-allowed}.lab-topo-status-badge{display:flex;align-items:center}.badge-route-wrapper{display:inline-flex;align-items:center;gap:10px;flex-wrap:wrap}.badge-route{display:inline-flex;align-items:center;gap:6px;padding:6px 12px;font:700 10px Courier New,monospace;letter-spacing:.02em;border:1px solid transparent}.badge-route.success{background:#e8f5e9;color:#1b5e20;border-color:#a5d6a7}.badge-route.danger{background:#ffebee;color:#c62828;border-color:#ef9a9a}.btn-quick-add-route{display:inline-flex;align-items:center;padding:6px 12px;background:var(--routing-orange);color:#fff;border:0;font:700 10px Arial,sans-serif;cursor:pointer;transition:opacity .15s ease}.btn-quick-add-route:hover{opacity:.88}.lab-topo-canvas{display:flex;flex-direction:column;gap:24px;padding:36px 28px 28px;background:#fafaf8;overflow-x:auto}.lab-topo-flow{display:flex;align-items:center;justify-content:space-between;gap:8px;min-width:860px}.topo-device-card{position:relative;display:flex;flex-direction:column;align-items:center;padding:20px 14px 16px;background:#fff;border:1px solid var(--routing-line);box-shadow:0 2px 8px #00000005;transition:all .25s ease}.device-pc1,.device-server{width:150px;flex-shrink:0}.device-r1,.device-r2{width:200px;flex-shrink:0}.topo-device-card.active-sender{border-color:var(--routing-orange);box-shadow:0 0 0 3px #ff4b122e}.topo-device-card.active-processing{border-color:var(--routing-orange);box-shadow:0 0 0 3px #ff4b1240;animation:pulseDevice 1.2s infinite}.topo-device-card.active-dropped{border-color:#c62828;box-shadow:0 0 0 3px #c6282840}.topo-device-card.active-target{border-color:#2e7d32;box-shadow:0 0 0 3px #2e7d3240}@keyframes pulseDevice{0%,to{transform:translateY(0)}50%{transform:translateY(-2px)}}.device-icon-box{display:flex;align-items:center;justify-content:center;width:48px;height:48px;margin-bottom:10px;background:#f5f5f0;border:1px solid var(--routing-line);color:var(--routing-ink)}.device-icon-box.router-box{background:#eef2ff;border-color:#c7d2fe;color:#3730a3}.device-icon-box.server-box{background:#f0fdf4;border-color:#bbf7d0;color:#166534}.device-name{font-size:13px;font-weight:700;color:var(--routing-ink);margin-bottom:3px}.device-ip{font:11px Courier New,monospace;color:var(--routing-orange);font-weight:600}.device-gw{margin-top:2px;font:9px Courier New,monospace;color:#777770}.device-network-tag{display:inline-block;margin-top:8px;padding:2px 6px;background:#f4f4f0;border:1px solid var(--routing-line);font:8px Courier New,monospace;color:#555550}.device-ports{display:flex;justify-content:space-between;width:100%;margin-top:10px;padding-top:8px;border-top:1px dashed var(--routing-line);font:9px Courier New,monospace;color:#666660}.port-item.left{text-align:left}.port-item.right{text-align:right}.device-routing-status{width:100%;margin-top:8px}.lookup-pill{display:inline-flex;align-items:center;justify-content:center;gap:5px;width:100%;padding:4px 6px;font:700 8px Courier New,monospace;background:#fff8e1;color:#b78103;border:1px solid #ffe082}.lookup-pill.drop{background:#ffebee;color:#c62828;border-color:#ef9a9a}.spin-fast{animation:spin .8s linear infinite}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.route-info{display:block;padding:3px 6px;font:700 8px Courier New,monospace;text-align:center}.route-info.active{color:#166534;background:#dcfce7;border:1px solid #86efac}.route-info.inactive{color:#991b1b;background:#fee2e2;border:1px solid #fca5a5}.topo-link-segment{flex:1;min-width:80px;display:flex;flex-direction:column;align-items:center;gap:8px;padding:0 4px}.topo-link-segment.link-wan{flex:1.35;min-width:120px}.cable-line{position:relative;width:100%;height:3px;background:var(--routing-line);transition:background .3s ease}.cable-line.wan-cable{height:5px;background:#d4d4cb;border-top:1px dashed #888880;border-bottom:1px dashed #888880}.cable-line.cable-active{background:var(--routing-orange)}.link-label{font:8px Courier New,monospace;color:#777770;white-space:nowrap;letter-spacing:.02em}.flowing-packet{position:absolute;top:-14px;transform:translate(-50%);display:inline-flex;align-items:center;padding:3px 8px;border-radius:12px;font:700 9px Courier New,monospace;white-space:nowrap;pointer-events:none;z-index:10}.packet-forward{background:var(--routing-orange);color:#fff;animation:packetFlowForward .9s cubic-bezier(.4,0,.2,1) infinite;box-shadow:0 2px 8px #ff4b1266}.packet-reply{background:#15803d;color:#fff;animation:packetFlowReply .9s cubic-bezier(.4,0,.2,1) infinite;box-shadow:0 2px 8px #15803d66}@keyframes packetFlowForward{0%{left:0%;opacity:0}15%{opacity:1}85%{opacity:1}to{left:100%;opacity:0}}@keyframes packetFlowReply{0%{left:100%;opacity:0}15%{opacity:1}85%{opacity:1}to{left:0%;opacity:0}}.lab-packet-inspector{display:flex;flex-direction:column;gap:10px;padding:16px 20px;background:#171717;border:1px solid #333330;color:#fff}.inspector-header{display:flex;align-items:center;gap:8px;padding-bottom:8px;border-bottom:1px solid #292929;color:var(--routing-orange);font:700 10px Courier New,monospace;letter-spacing:.06em}.inspector-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:16px}.insp-item{display:flex;flex-direction:column;gap:4px}.insp-item small{font:700 9px Courier New,monospace;color:#888880;letter-spacing:.04em;text-transform:uppercase}.insp-item code{font:11px Courier New,monospace;color:#38bdf8;word-break:break-all}.lab-cli-output{display:flex;flex-direction:column;border:1px solid #333330;background:#0d0d0d}.cli-bar{display:flex;align-items:center;gap:8px;padding:8px 16px;border-bottom:1px solid #262626;background:#1a1a1a;color:#b2b2aa;font:10px Courier New,monospace}.lab-cli-output pre{margin:0;padding:16px 20px;color:#deded8;font:11px/1.6 Courier New,monospace;white-space:pre-wrap;max-height:200px;overflow-y:auto}.lab-topo-footer{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:18px 24px;border-top:1px solid var(--routing-line);background:#ebebe6;flex-wrap:wrap}.lab-topo-narration{display:flex;align-items:center;gap:12px;flex:1;min-width:280px}.status-dot{width:9px;height:9px;border-radius:50%;flex-shrink:0;background:#888880}.status-dot.active{background:var(--routing-orange);animation:pulseDot 1s infinite alternate}.status-dot.success{background:#16a34a}.status-dot.danger{background:#dc2626}@keyframes pulseDot{0%{transform:scale(.9);opacity:.6}to{transform:scale(1.3);opacity:1}}.lab-topo-narration p{margin:0;font-size:13px;line-height:1.45;color:var(--routing-ink);font-weight:500}.lab-topo-actions{display:flex;align-items:center;gap:10px}.lab-btn-primary{display:inline-flex;align-items:center;gap:8px;padding:11px 20px;border:0;background:var(--routing-orange);color:#fff;font:700 11px Arial,sans-serif;cursor:pointer;transition:all .15s ease}.lab-btn-primary:hover{background:#e03e09}.lab-btn-secondary{display:inline-flex;align-items:center;gap:8px;padding:11px 20px;border:0;background:#242422;color:#fff;font:700 11px Arial,sans-serif;cursor:pointer;transition:all .15s ease}.lab-btn-secondary:hover{background:#3b3b38}.interface-section{display:grid;grid-template-columns:.85fr 1.5fr;gap:80px;background:#ecece8}.interface-panel{padding:24px;background:var(--routing-paper);border:1px solid var(--routing-line)}.interface-form{display:grid;grid-template-columns:1fr 1fr;gap:12px}.interface-form label{display:flex;flex-direction:column;gap:7px;color:#777770;font:9px Courier New,monospace;text-transform:uppercase}.interface-form input{min-width:0;padding:10px;border:1px solid var(--routing-line);color:var(--routing-ink);background:#fff;font:12px Courier New,monospace;outline-color:var(--routing-orange)}.interface-form label:nth-child(3){grid-column:1 / 2}.interface-form button{align-self:end;display:inline-flex;align-items:center;justify-content:center;gap:7px;min-height:37px;padding:0 13px;color:#fff;background:var(--routing-orange);border:0;font-size:10px;font-weight:700;cursor:pointer}.interface-list{margin-top:28px;border-top:1px solid var(--routing-line)}.interface-row{display:grid;grid-template-columns:10px 1.1fr 1.1fr 1fr .7fr;gap:12px;align-items:center;min-height:56px;border-bottom:1px solid var(--routing-line);font-size:10px}.interface-row code{color:var(--routing-orange);font:10px Courier New,monospace}.interface-row>span:not(.interface-status){color:#777770}.interface-row small{color:#14783c;font:9px Courier New,monospace}.interface-status{width:7px;height:7px;border-radius:50%;background:#14783c}.interface-status.disabled{background:#b42318}.route-table-section{display:grid;grid-template-columns:.85fr 1.5fr;gap:80px;background:#ecece8}.route-panel{padding:24px;background:var(--routing-paper);border:1px solid var(--routing-line)}.route-form{display:grid;grid-template-columns:1fr 1fr 100px auto;gap:10px;align-items:end}.route-form label{display:flex;flex-direction:column;gap:7px;color:#777770;font:9px Courier New,monospace;text-transform:uppercase}.route-form input{min-width:0;padding:10px;border:1px solid var(--routing-line);color:var(--routing-ink);background:#fff;font:12px Courier New,monospace;outline-color:var(--routing-orange)}.route-form button{display:inline-flex;align-items:center;gap:7px;height:37px;padding:0 13px;color:#fff;background:var(--routing-orange);border:0;font-size:10px;font-weight:700;cursor:pointer}.route-table{margin-top:28px;border-top:1px solid var(--routing-line)}.route-table-head,.route-row{display:grid;grid-template-columns:1.3fr 1.1fr 1.1fr .8fr;gap:12px;align-items:center}.route-table-head{padding:10px 0;color:#777770;font:9px Courier New,monospace}.route-row{min-height:50px;border-top:1px solid var(--routing-line);color:#65655e;font-size:10px}.route-row code{color:var(--routing-orange);font:10px Courier New,monospace}.route-success{display:flex;align-items:center;gap:7px;margin:20px 0 0;color:#14783c;font-size:11px}.lookup-section{display:grid;grid-template-columns:.85fr 1.5fr;gap:80px}.lookup-panel{align-self:center;padding:24px;background:#ecece8;border:1px solid var(--routing-line)}.lookup-panel>label{display:block;margin-bottom:8px;color:#777770;font:9px Courier New,monospace;text-transform:uppercase}.lookup-input{display:flex;align-items:center;gap:12px}.lookup-input input{width:180px;padding:11px;border:1px solid var(--routing-line);color:var(--routing-ink);background:#fff;font:12px Courier New,monospace;outline-color:var(--routing-orange)}.lookup-input>span{color:var(--routing-orange);font-size:18px}.lookup-input strong{color:var(--routing-orange);font:12px Courier New,monospace}.lookup-result,.lookup-error{display:flex;align-items:flex-start;gap:8px;margin:24px 0 0;padding-top:18px;border-top:1px solid var(--routing-line);color:#14783c;font-size:12px;line-height:1.35}.lookup-result p{margin:0}.lookup-result svg{flex:0 0 auto}.lookup-error{color:#b42318}.terminal-section{background:#171717;color:#fff}.terminal-section .routing-eyebrow{color:#96968e}.terminal-section .routing-heading h2{color:#fff}.terminal-panel{max-width:760px;margin-top:65px;border:1px solid #3b3b38;background:#0d0d0d}.terminal-title{display:flex;align-items:center;gap:8px;padding:12px 15px;border-bottom:1px solid #3b3b38;color:#b2b2aa;font:10px Courier New,monospace}.terminal-title svg{color:var(--routing-orange)}.terminal-title span{margin-left:auto;color:#76250f}.terminal-panel pre{min-height:250px;max-height:350px;overflow:auto;margin:0;padding:18px;color:#deded8;font:11px/1.55 Courier New,monospace;white-space:pre-wrap}.terminal-input{display:flex;gap:9px;padding:12px 15px;border-top:1px solid #3b3b38;color:var(--routing-orange);font:12px Courier New,monospace}.terminal-input input{flex:1;min-width:0;color:#fff;background:transparent;border:0;outline:0;font:inherit}.terminal-input input::placeholder{color:#66665f}.command-chips{display:flex;flex-wrap:wrap;gap:8px;max-width:760px;margin-top:15px}.command-chips button{padding:7px 10px;color:#b2b2aa;background:#242422;border:1px solid #3b3b38;font:10px Courier New,monospace;cursor:pointer}.command-chips button:hover{color:#fff;border-color:var(--routing-orange)}.diagnostic-section{display:grid;grid-template-columns:.85fr 1.5fr;gap:80px;background:#ecece8}.diagnostic-panel{padding:24px;background:var(--routing-paper);border:1px solid var(--routing-line)}.diagnostic-steps{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--routing-line)}.diagnostic-steps button{display:flex;flex-direction:column;align-items:flex-start;min-height:150px;padding:17px;border:0;text-align:left;background:var(--routing-paper);cursor:pointer}.diagnostic-steps button:nth-child(2){background:#e3e3de}.diagnostic-steps button:nth-child(3){color:#fff;background:var(--routing-orange)}.diagnostic-steps button:hover{outline:2px solid var(--routing-orange);outline-offset:-2px}.diagnostic-steps span{margin-bottom:auto;color:var(--routing-orange);font:9px Courier New,monospace}.diagnostic-steps button:nth-child(3) span{color:#76250f}.diagnostic-steps strong{font-size:14px}.diagnostic-steps small{margin-top:7px;color:#777770;font:9px Courier New,monospace}.diagnostic-steps button:nth-child(3) small{color:#76250f}.diagnostic-output{display:flex;align-items:flex-start;gap:8px;margin-top:20px;padding:14px;color:#14783c;background:#e6f4eb;font-size:11px;line-height:1.35}.diagnostic-output.is-error{color:#b42318;background:#fcebea}.routing-next{display:flex;align-items:end;justify-content:space-between;padding:110px clamp(28px,6vw,100px) 130px;background:var(--routing-orange)}.routing-next h2{margin-bottom:0;font-size:clamp(3rem,6vw,6.5rem)}.routing-button{display:inline-flex;align-items:center;gap:24px;padding:14px 17px;color:#fff!important;background:var(--routing-ink);font-size:11px;font-weight:600}.routing-button svg{transition:transform .2s ease}.routing-button:hover svg{transform:translate(4px)}@media(prefers-reduced-motion:reduce){.routing-link.is-running i{animation:none}}@media(max-width:720px){.routing-nav{padding:0 18px}.routing-nav>span:nth-child(2){display:none}.routing-hero{display:block;padding:76px 20px 70px}.routing-hero h1{font-size:clamp(3.2rem,15vw,5rem)}.routing-hero-illustration{margin-top:45px}.routing-hero-illustration img{min-height:240px}.routing-section{padding:70px 20px}.routing-concept-grid,.interface-section,.route-table-section,.lookup-section,.diagnostic-section{display:block}.topology-section{display:flex;flex-direction:column;gap:24px}.lab-topo-toolbar{padding:14px 16px}.lab-topo-btn-group{width:100%;overflow-x:auto}.lab-topo-btn{flex:1;text-align:center;padding:7px 8px;font-size:10px;white-space:nowrap}.lab-topo-canvas{padding:20px 14px}.inspector-grid{grid-template-columns:repeat(2,1fr)}.lab-topo-footer{padding:14px 16px;flex-direction:column;align-items:stretch}.lab-topo-actions{width:100%}.lab-btn-primary,.lab-btn-secondary{width:100%;justify-content:center}.routing-concept-grid article{min-height:180px;border-bottom:1px solid var(--routing-line)}.routing-concept-grid article:last-child{border-bottom:0}.routing-concept-grid article>span{margin-bottom:30px}.interface-panel{margin-top:35px;padding:17px}.interface-form{grid-template-columns:1fr}.interface-form label:nth-child(3){grid-column:auto}.interface-form button{margin-top:3px}.interface-list{overflow-x:auto}.interface-row{min-width:620px}.route-panel{margin-top:35px;padding:17px}.route-form{grid-template-columns:1fr}.route-form button{justify-content:center}.route-table{overflow-x:auto}.route-table-head,.route-row{min-width:570px}.lookup-panel,.diagnostic-panel{margin-top:35px;padding:17px}.lookup-input{flex-wrap:wrap}.lookup-input input,.lookup-input strong{width:100%}.terminal-panel{margin-top:35px}.diagnostic-steps{display:block}.diagnostic-steps button{min-height:120px;border-bottom:1px solid var(--routing-line)}.diagnostic-steps button:last-child{border-bottom:0}.routing-next{display:block;padding:80px 20px 90px}.routing-button{margin-top:35px}}