By default a Mapbiquity web map will expand to fill the space it's given. For example, if placed in an empty body tag, the map will fill the entire page. This behavior works in most circumstances, but occasionally you need to constain the proportions of the map so it's just the way you want it.
All we need to do to accomplish this is add a parent tag around the mapContainer tag that defines the size. The following code constrains the web map to be a 400 pixel by 400 pixel square:
<div style="width:400px; height:400px;">