For some gadgets, you can set the height of the gadget within the gadget settings. For other gadgets, you can set the height of the layout cell in which the gadget appears.
The width of a gadget usually depends on its content and the layout cell or placeholder in which it appears. For some gadgets, you can control the width through their settings. For all gadgets, you can control the gadget width by entering the following code in the Inline style setting:
width: 250;
where the value of 250 can be replaced by whatever pixel value you choose.