JSFiddle - React, Tailwind, and code Playground
HTML
<div id="div1">DIV 1</div>
<div id="div2">DIV 2</div>
JavaScript
$("#div1").animate({opacity:.1},1000,function(){
$("#div2").animate({opacity:.1},1000);
});
<div id="div1">DIV 1</div>
<div id="div2">DIV 2</div>
$("#div1").animate({opacity:.1},1000,function(){
$("#div2").animate({opacity:.1},1000);
});