JSFiddle - React, Tailwind, and code Playground

JavaScript

function rgbtohex(val) {
 var clean = val.replace(/[^0-9\.,]/g, "");
 var colors = clean.split(',');
 var r = colors[0];
 var g = colors[1];
 var b = colors[2];
 
  return "#" + ((1 << 24) + (r << 16) + (g << 8) + b).toString(16).slice(1);
}