Fail-open handling

<div class="sd"><div class="sd-head"><strong>FAIL OPEN</strong><span id="state">live check</span></div><div class="sd-stage"><div class="fo-error">POLICY CHECK: ERROR</div><div class="fo-split"><div class="fo-lane"><span>fail open</span><div id="open-door">OPEN</div><b>request passes</b></div><div class="fo-lane"><span>fail closed</span><div id="closed-door">CLOSED</div><b>request stops</b></div></div></div><div class="sd-foot"><span id="caption">checking boundary</span><span>tap to step</span></div></div>

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let n=0;function advance(){n=1-n;document.querySelectorAll('.fo-lane').forEach((e,i)=>e.classList.toggle('active',i===n));document.getElementById('state').textContent=n?'safe default':'unsafe default';document.getElementById('caption').textContent=n?'error denies and rolls back':'error accidentally grants access'}advance();setInterval(advance,900);
document.querySelector('.sd').addEventListener('pointerdown',advance);