절정·대미 법칙

<div class="journey"><div class="head">EXPERIENCE OVER TIME <b id="ending">STRONG END</b></div><svg viewBox="0 0 400 150" preserveAspectRatio="none"><polyline points="10,100 90,92 170,30 250,98 325,86 390,32" id="line"/><circle cx="170" cy="30" r="7"/><circle cx="390" cy="32" r="7" id="last"/></svg><div class="labels"><span>START</span><span>PEAK</span><span>END</span></div></div>

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const line=document.querySelector('#line');const last=document.querySelector('#last');const ending=document.querySelector('#ending');let high=true;function flip(){high=!high;line.setAttribute('points','10,100 90,92 170,30 250,98 325,86 390,'+(high?32:120));last.setAttribute('cy',String(high?32:120));ending.textContent=high?'STRONG END':'ROUGH END'}setInterval(flip,1500);