I am trying to produce intro on our web site (www.adriaticglobal.net) with mask overlay with the 75% height of user screen following this lesson https://mdbootstrap.com/education/bootstrap/landing-page-lesson-1/ (this is for 100% height)

When we put height class (such as h-50 or h-75) result is always incostient, as it seems that height classes are nested. Either mask or intro element are too big or too small.

I would like to put this mask away from the header and use a simple section tag called intro which will come after header. This section needs to cover 75% of screen after header, not to cover full height of view.

So I need to have a - navbar

• after navbar comes breadcrumbs (if any)

• intro mask height 75% of the browser window.

• page body

Thanks in advance.