text: (function() {
      'use strict';
  
      var canvas = document.getElementById('canvas');
  
      var engine = new Shape.Engine(canvas);
      var promise = new Promise((resolve) => { resolve(); });
      
  //    document.getElementById('go').addEventListener('click', start);
      start();
      function start() {
          document.getElementById('go').removeEventListener('click', start);
          promise.then(() => engine.toText('悦'))
          .then(() => engine.shake())
  	    .then(() => engine.toText('刻'))
          .then(() => engine.shake())
  	    .then(() => engine.toText('经销商'))
          .then(() => engine.shake())
  	    .then(() => engine.toText('雄起'))
          .then(() => engine.shake())
  	    .then(() => engine.toText('咱们组'))
          .then(() => engine.shake())
  	    .then(() => engine.toText('牛逼'))
          .then(() => engine.shake())
  	    .then(() => engine.toText('！'))
          .then(() => engine.shake())
  	    .then(() => engine.toText(''))
          .then(() => engine.shake())
          .then(() => engine.clear())
          .then(() => document.getElementById('go').addEventListener('click', start));
      }
  })();
  