Change metabox height

I am using Ultimate Client. I am creating a new widget in control panel back end. The widget area has to be set in px:

[advanced_iframe securitykey=”capi$32tano33$” src=”https://*******/borettslag-faq” id=”iframe1″ name=”iframe1″ width=”100%” height=”1600″ ]

This is the code i use now. The hight is always too big. However, when the height is set with % it doesn’t look good.

Can the height be adjusted to fit the element automatically, based on screen size and so on?