Cost per acquisition (CPA)

<div class="funnel"><div class="step"><span>AD SPEND</span><b>$600</b></div><div class="flow" id="clicks"></div><div class="step"><span>CONVERSIONS</span><b id="conversions">6</b></div><div class="result">CPA <strong id="cpa">$100</strong></div></div>

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const flow=document.querySelector('#clicks');flow.innerHTML=Array.from({length:12},()=>'<i></i>').join('');let step=0;function draw(){const count=[6,4,8,5][step++%4];[...flow.children].forEach((dot,i)=>{dot.className=i<count?'convert':'drop'});document.querySelector('#conversions').textContent=String(count);document.querySelector('#cpa').textContent='$'+(600/count).toFixed(0)}draw();setInterval(draw,1400);