ArcGIS Online Instant App's Category Gallery: how to remove the header

[ScottHansen__MDP_]

In ArcGIS Online Instant App's Category Gallery, is there a way a remove the header? I want to incorporate this application into ArcGIS Hub, which already has its own row and header. The only option I am aware of is the Custom Header HTML dialog box, but there is no code available to modify. In the future, it would be nice if ESRI could provide users with an option to toggle a header on or off.

AGOL Instant App's Category Gallery and option to remove header.

[BethRomero · Accepted solution]

@ScottHansen__MDP_ You can hide the header with custom CSS. This option can be found in Theme & Layout > Gallery theme & layout > Custom CSS.  Add in the following, and header should be hidden

header {
display:none;}