JSFiddle - React, Tailwind, and code Playground

HTML

<div id="clockDisplay">sfd</div>

JavaScript

function renderTime(offset) {

var currentTime = new Date();
currentTime.setHours(currentTime.getHours()+offset);
var diem = "AM";
var h = currentTime.getHours();
var m = currentTime.getMinutes();
var s = currentTime.getSeconds();


if (h == 0) {
    h = 12
} else if (h > 12) {
    h = h - 12;
    diem = "PM";
}

if (h < 10) {
    h = "0" + h;
}

if (m < 10) {
    m = "0" + m;
}

if (s < 10) {
    s = "0" + s;
}

var myClock = document.getElementById ("clockDisplay");
myClock.textContent = h + ":" + m + ":" + s + " " + diem;


setTimeout ('renderTime()', 1000);

}

renderTime(-2);