Using getComputedStyle()
==============================
Get the computed style for a webpage. This gives you always some values, even if they are missing and not defined in the stylesheets.
```
/**
* Get values for left and top from element and add 10px to each.
*/
var element = document.getElementById('someId'),
style = window.getComputedStyle(element),
left = parseInt(style.left),
top = parseInt(style.top);
element.style.left = left + 10 + "px";
element.style.top = top + 10 + "px";
```
Reference and read more
------------------------------
[Window.getComputedStyle()](https://developer.mozilla.org/en-US/docs/Web/API/Window.getComputedStyle)
[Can I Use ](http://caniuse.com/#feat=getcomputedstyle)
Revision history
------------------------------
2014-10-07 (A, mos) A First try.