JSFiddle - React, Tailwind, and code Playground

JavaScript

function select(selector){
  selector = selector || '';
	var selectorType = selector.match(/^#/) ? 'ID' : selector.match(/^\./) ? 'CLASS' : 'ELEMENT';
  
  switch(selectorType){
  	case 'ID':
    	return document.getElementById(selector);
    case 'CLASS':
    	return document.getElementsByClassName(selector)
    case 'ELEMENT'  
  }
  
}