JSFiddle - React, Tailwind, and code Playground

HTML

<div class="confession" style="border:3px solid #DDD;">This is your div</div>

JavaScript

//$(".confession").delay(5000).animate({borderWidth: "0"}, 500);

function shrinkBorder(){
    var e = $(".confession");
    var eBorderWidth = e.css("border-width");
    if(eBorderWidth != "0px"){
        e.css("border-width",(eBorderWidth.split("px")[0]-1));
        setTimeout(shrinkBorder, 50);
    }
}

setTimeout(shrinkBorder, 5000);