Hi Ariel,
Normally I would say to create a class and do you styling on that. However sometimes this is (sadly) not possible. You can use JS for that with the following syntax:
var ObjectInDom = document.getElementsByClassName('ClassName')[0]; // Make sure you can identify only 1 object
ObjectInDom.style.setProperty('height', '100%');
In the setProperty you can put whatever style you want. See https://www.w3schools.com/jsref/met_cssstyle_setproperty.asp
Good luck
well some ways are
1.write a nanoflow on the page add the javascript call to it
in that java script call u can write any java script code which will work.
2.add the HTMl snippet and add the javascript there.