Generally speaking, changing height of the menu is not supported out of the box. In order to customize the presentation of any particular widget, you could use a CSS selector with the widget’s specific CSS class - this action will override the default styling. You could get the right selector as inspect the HTML output with Firebug. For example this snippet can be used for changing height of your menu:
Also, I believe you might find this topic
from our online documentation very useful.
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