Document.querySelector()

https://developer.mozilla.org/en-US/docs/Web/API/Document/querySelector

Document.createElement()

https://developer.mozilla.org/en-US/docs/Web/API/Document/createElement

ElementCSSInlineStyle.style

https://developer.mozilla.org/en-US/docs/Web/API/ElementCSSInlineStyle/style

ParentNode.append()

https://developer.mozilla.org/en-US/docs/Web/API/ParentNode/append

Node.appendChild()

https://developer.mozilla.org/en-US/docs/Web/API/Node/appendChild

const app = function () {
  const game = {};

  function init() {
    console.log('init ready');
    game.main = document.querySelector('#game');
    console.log(game);
    game.scoreboard = document.createElement('div');
    game.scoreboard.textContent = "Dealer 0 vs Player 0";
    game.scoreboard.style.fontSize = "2em";
    game.main.append(game.scoreboard);
  }
  return {
    init: init
  }
}();