CSS - Animate display none, block and opacity

Place to talk about website HTM elements, CSS style and design, and get help with HTML, CSS codes.
PloMar
Posts: 48

CSS - Animate display none, block and opacity

I have a Div and a Button that uses JavaScript to alternate the class of the Div to "hide" and "show". The "hide" class has "display:none;" to hide the Div (and opacity 0), and the "show" class has "display:block;" to show the Div (and opacity 1).
Is it possible to animate the display none /block and opacity using only CSS?
This is the code:

Code: Select all

<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8" />
<title>Title</title>
<style>
#cnt1 {
  position: relative;
  margin: 4px auto;
  background:#eee;
}
#cnt1.hide {
  opacity : 0;
  display: none;
}
#cnt1.show {
  opacity:1;
  display: block;
  width: 75%;
  height: 150px;
}
</style>
</head>
<body>
<div id="cnt1" class="show">
  <p>Content to be displayed</p>
  <p>Other paragraph with content to be displayed</p>
</div>
<button id="btn1">Hide</button>
<script>
// get the htmll elements
var cnt1 = document.getElementById('cnt1');
var btn1 = document.getElementById('btn1');

// register click event to #btn1 that alternate class to #cnt1, and changes #btn1 text
btn1.addEventListener('click', function() {
  if(cnt1.className == 'show') {
    cnt1.className = 'hide';
    btn1.innerHTML = 'Show'
  }
  else {
    cnt1.className = 'show';
    btn1.innerHTML = 'Hide';
  }
});
</script>
MarPlo Posts: 186
The "display: none;" and "display: block;" are executed instantly, from what I know, you cannot animate them with only CSS. But to achieve the animation hide /show effect with CSS, you can use "transition" property and set the "height" and "width" to 0 for ".hide" (it will animate also the opacity).
Test this code:

Code: Select all

<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8" />
<title>Title</title>
<style>
#cnt1 {
  position: relative;
  margin: 4px auto;
  background:#eee;
}
#cnt1.hide {
  opacity : 0;
  width: 0;
  height:0;
  transition: height, 1s linear;
}
#cnt1.hide * {
  display: none;  /* needed to hide the content in that Div */
}
#cnt1.show {
  opacity:1;
  width: 75%;
  height:150px;
  transition: height, 1s linear;
}
</style>
</head>
<body>
<div id="cnt1" class="show">
  <p>Content to be displayed</p>
  <p>Other paragraph with content to be displayed</p>
</div>
<button id="btn1">Hide</button>
<script>
// get the htmll elements
var cnt1 = document.getElementById('cnt1');
var btn1 = document.getElementById('btn1');

// register click event to #btn1 that alternate class to #cnt1, and changes #btn1 text
btn1.addEventListener('click', function() {
  if(cnt1.className == 'show') {
    cnt1.className = 'hide';
    btn1.innerHTML = 'Show'
  }
  else {
    cnt1.className = 'show';
    btn1.innerHTML = 'Hide';
  }
});
</script>
</body>
</html>
Demo:

Content to be displayed

Other paragraph with content to be displayed

Similar Topics