WebTransport

<div class="n-demo"><div class="n-head"><strong>WEBTRANSPORT SESSION</strong><span>LIVE TRACE</span></div><div class="n-stage"><div class="wt"><div class="wt-lane"><span>BIDI</span><i id="wt0"></i><b>⇄</b></div><div class="wt-lane"><span>UNI</span><i id="wt1"></i><b>→</b></div><div class="wt-lane"><span>DGRAM</span><i id="wt2"></i><b>→</b></div></div></div><div class="n-foot">tap to step · auto replay</div></div>

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let step=0;function advance(){const widths=[[22,9,13],[43,31,55],[66,67,20],[91,83,79]];widths[step].forEach((v,i)=>document.getElementById('wt'+i).style.width=v+'%');step=(step+1)%4}
const clickTarget=document.querySelector('.n-demo');if(clickTarget&&typeof advance==='function'){advance();const timer=setInterval(advance,1050);clickTarget.addEventListener('pointerdown',()=>{clearInterval(timer);advance()})}