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                <p>This demonstrates a way of providing feedback without getting in the way.</p>
<p>It’s kind of like the feedback you get in platform video games like Mario Bros.</p>
<p>When you get points, the gameplay isn’t interrupted.</p>
<p>Instead, a small bit of feedback drifts upwards and disappears.</p>
<button>Click me!</button>




                function giveFeedback(element, feedbackContent) {
    var feedback = document.createElement('span');
    feedback.setAttribute('role', 'status');
    feedback.innerHTML = feedbackContent;
    var elementBox = element.getBoundingClientRect();
    var feedbackBox = feedback.getBoundingClientRect();
    var y = Math.round(( + window.scrollY) - feedbackBox.height);
    var x = Math.round((elementBox.left + window.scrollX + (elementBox.width/2)) - (feedbackBox.width/2)); = 'absolute'; = x + 'px'; = y + 'px'; = 1; = 'transform .75s, opacity .75s'; = 'translateY(-75px)'; = 0;
    feedback.addEventListener('transitionend', function () {
      if (feedback.parentNode) {
    }, false);

document.querySelector('button').addEventListener('click', function(ev) {
  giveFeedback(this, 'Yay!');