Threat modeling

<div class="sd"><div class="sd-head"><strong>THREAT MODEL</strong><span id="state">live check</span></div><div class="sd-stage"><div class="flow"><div class="tile" id="user">user input</div><div class="edge" id="edge1"></div><div class="tile" id="api">API</div><div class="edge" id="edge2"></div><div class="tile" id="db">data store</div></div><div class="risk" id="risk">boundary 1</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.getElementById('edge1').classList.toggle('hot',!n);document.getElementById('edge2').classList.toggle('hot',!!n);document.getElementById('risk').textContent=n?'storage permission':'untrusted input';document.getElementById('state').textContent=n?'boundary 2':'boundary 1';document.getElementById('caption').textContent=n?'check access to stored data':'validate input at entry'}advance();setInterval(advance,950);
document.querySelector('.sd').addEventListener('pointerdown',advance);