Change Size action can change size of selected element.
If the new value of width/height starts with "+" or "-", that means it is a relative value. For example, the value of new width is "+=50" means horizontal enlarge the element for 50 pixels; if the value of new width is "50", means setting the element width to 50 pixels.
You can use property value in the new width and/or height.
At the bottom of the window you can also see an "Animation" option, turning on this option will easily apply animation on the resizing. You can also specify the duration of the animation.
This action is available for all elements.