The latest version uses Axios to call Stujo's Tic Tac Toe API and SweetAlert2 for game notifications and starting new games.
Codepen with Axios and SweetAlert2: https://codepen.io/c-herr/pen/MpMxVw
Codepen of original version with jQuery and regular alerts: http://codepen.io/c-herr/full/LRrNKg/