JSFiddle - React, Tailwind, and code Playground
HTML
<div id="buttons">
<input type="button" id="btn1" value="click!"/>
<input type="button" id="btn2" value="click!"/>
<input type="button" id="btn3" value="click!"/>
<input type="button" id="btn4" value="click!"/>
<input type="button" id="btn5" value="click!"/>
<input type="button" id="btn6" value="click!"/>
<input type="button" id="btn7" value="click!"/>
<input type="button" id="btn8" value="click!"/>
</div>
<div id="div1">1</div>
<div id="div2">2</div>
<div id="div3">3</div>
<div id="div4">4</div>
<div id="div5">5</div>
<div id="div6">6</div>
<div id="div7">7</div>
<div id="div8">8</div>
JavaScript
$("#buttons").on("click",":button",function(e){
$("#div"+$(this).attr("id").replace(/[^0-9]/g, '')).css("background","red");
});