Problem with Width and Height on iframed embedded reports

Problem with Width and Height on iframed embedded reports

I am trying to make the embedded report to take 100% of the widget width and height but the only values that works are pixels. Is there any way to use auto, 100%, etc

This is a page with two widget. The top widget shows master records and the widget below shows related records separated in tabs. Within each tab, I am filtering the report to show the related records corresponding with the master record thru a hidden lookup field I have on each separate form. I will pass that as parameter but my problem is about the report width and height.

 This is how I am showing the report within each tab. I am hardcoding the master record id but I know how to do that. 

  1. else if(tab == "tab3")
  2. {
  3. %>
  4. <iframe src="https://creatorapp.zoho.com/#####/onboarding/report-embed/Onboarding_Employee_Roster?fbo_id=4016256000000716007" height="300px" width="1200px"></iframe>
  5. <%
  6. }

If i add anything other than fixed pixels it will not take it. Any solution for this? Not even in the widget settings you can use auto or 100%.

I have also tried to inspect the page to modify the CSS but cant find the correct style block