Translating an elements Y axis 50% will move it down 50% of its own height, not 50% of the parents height as I would expect. How do I tell a translating element to base it\'
What works for me using only CSS is:
.child {
position: relative;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
/* Backward compatibility */
-webkit-transform: translate(-50%, -50%);
-moz-transform: translate(-50%, -50%);
-o-transform: translate(-50%, -50%);
-ms-transform: translate(-50%, -50%);
}
How it works:
The solution to this problem is not to use translate at all. When you are translating an element, the percentage you select is based on it's own height.
If you want to position the element based on the parent's height, use top: 50%;
So the code will look like this:
body {
margin: 0;
width: 100%;
height: 100%;
}
body > div {
width: 200px;
height: 200px;
background: #ff0;
position: relative;
}
body > div > div {
position: absolute;
top: 50%;
width: 10%;
height: 10%;
/* -webkit-transform: translateY(50%); */
background: #f00;
}
Its forked with positioning required on the following URL working sample
body {
margin: 0;
width: 100%;
height: 100%;
}
body>div {
position: relative;
width: 200px;
height: 200px;
background: #ff0;
}
body>div>div {
position: absolute;
left: 50%;
top: 50%;
width: 10%;
height: 10%;
background: #f00;
transform: translate(-50%, -50%);
}
notes :