CSS3 transition glitch in Chrome

Question

I have a simple modal, which opens up upon :checked input. In Firefox and IE the transition animation works fine, but in Chrome it glitches (effect not smooth) when it shows up upon checking the input.

Demo fiddle: JsFiddle

When i remove visibility: hidden it works fine, but then the modal blocks the rest of the page under neath it - no text can be selected, no buttons clicked etc.

Any ideas on how to make the transition smooth in Chrome?

Answer 1

Answer

You declared transform: none; on your modal div. Just define a rotationX instead, so your animation has a starting and ending point. That solves the animation issue:

input#switch:checked ~ #test > div {
    transform: rotateX(0deg);
}

http://jsfiddle.net/s8hts3v7/9/

Code Snippet

#test {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,0.8);
  z-index: 9999999;
  visibility: hidden;
}
input#switch:checked ~ #test {
  visibility: visible;
}
#test > div {
  background: #fff;
  width: 300px;
  height: 100px;
  padding: 30px;
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  margin: auto;
  transform: perspective(300px) rotateX(-90deg);
  transform-origin: top center;
  transition: 0.4s ease;
}
input#switch:checked ~ #test > div {
  transform: rotateX(0deg);
}
#test > div label {
  background: #000;
  color: #fff;
  display: block;
  text-align: center;
  padding: 8px;
  margin-top: 20px;
  cursor: pointer;
}

<input id="switch" type="checkbox" name="test-chkbox" />
<label for="switch">Open modal</label>

<div id="test">
    <div>Lorem Ipsum is simply dummy text of the printing and typesetting industry.
    <label for="switch">Close modal</label>
    </div>
</div>