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HTML

CSS

CSS Base

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JavaScript

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HTML

              
                <button type="button" class="btn-crazy btn btn-lg btn-danger">
  Click Me!
</button>
<button type="button" class="btn-crazy btn btn-lg btn-primary">
  Click Me!
</button>
<button type="button" class="btn-crazy btn btn-lg btn-success">
  Click Me!
</button>
              
            
!

CSS

              
                body, .jumbotron { padding: 30px; }
.text-giant      { font-size: 40px; }
.btn-crazy       {
  position: absolute;
  top: 30px;
  left: 35%;
  width: 30%;
  transition: 0.5s ease all;
  text-align: center;
}
              
            
!

JS

              
                // grab everything we need
const crazyButtons = document.querySelectorAll('.btn-crazy');

// define our functions
function goCrazy() {
  // get a random number for the left offset
  // random num for top offset
  const offsetHorizontal = Math.random() * (window.innerWidth - this.clientWidth);
  const offsetVertical  = Math.random() * (window.innerHeight - this.clientHeight);

  // apply those numbers to the button
  this.style.top = `${offsetVertical}px`;
  this.style.left = `${offsetHorizontal}px`;
}

// add event listeners
crazyButtons.forEach(button => button.addEventListener('mouseenter', goCrazy));
              
            
!
999px

Console