jquery-style queryselector shortcut at $ and a most barebones script loader

looseChance.js

if(!$)var $=a=>{let r=document.querySelectorAll(a);return r.length>1?r:r[0]} // $('.class > div#heading') etc. returns an array if more than one match is found
((l,Z)=>{var d=(a)=>{return new Promise((c,d)=>{var b=document.createElement("script");b.onload=c,b.onerror=d,b.async=1,b.src=a,document.head.appendChild(b)})};Promise.all(l.split(",").map(a=>{return d('lib/'+a+'.js')})).then(Z)})(
  'api,auth,../main', // loads lib/api.js, lib/auth.js & main.js. if your file layout is differnet, edit the call to d() at 2:201
  X=>{console.log('scripts loaded')} // callback function to run when scripts have loaded
)