this is how it should look but when I paste the same code:
<!-- dummy div -->
<div style="height:100px;">
</div>
<!-- outer div to contain inner div (that has a margin) -->
<div style="height:80vh;">
<!-- inner most div now has its boundary defined by the outer div, so adding a border wont extend its width beyond the width of the browser window -->
<div style="height:80vh; padding: 20px;">
<!-- iframe set to fill 100% of its containing div -->
<iframe src="http://insitu-app.com/insitu-tgrg-simplified.html" style="top:0; left:0; height: 100%; width: 100%; margin-left: auto; margin-right: auto; border: none" frameborder="0" allowfullscreen></iframe>
</div>
</div>
into the wordpress code editor and publish, this is what I get . I want the div tag and its contents to take up 80% of the viewports vertical height. If this method isn't possible on wordpress and they're is an alternative please tell me? Many Thanks