TLS handshake

<div class="n-demo"><div class="n-head"><strong>TLS HANDSHAKE</strong><span>LIVE TRACE</span></div><div class="n-stage"><div class="tls-side n-box">CLIENT</div><div class="tls-wire"><div id="tls-msg" class="n-box mono">ClientHello →</div><div id="tls-lock" class="tls-lock">OPEN CHANNEL</div></div><div class="tls-side n-box">SERVER</div></div><div class="n-foot">tap to step · auto replay</div></div>

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const tlsMessages=['ClientHello →','← ServerHello + cert','derive traffic keys','secure data'];let step=2;function advance(){document.getElementById('tls-msg').textContent=tlsMessages[step];document.getElementById('tls-lock').classList.toggle('n-on',step===3);document.getElementById('tls-lock').textContent=step===3?'PROTECTED CHANNEL':'OPEN CHANNEL';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()})}