Custom screen size for embedded experience builder app

[CorporateGeospatial]

Hi all, we are looking to embed experience builder apps on web pages using a frame smaller than the options provided by the experience builder in AGOL, specifically 1024 x 500 pixels.

Is there any way to create an experience builder app in a custom size different than the options provided (shown below) out of the box? I am aware of the different sizing options for tablet and mobile but these are not applicable for this purpose.

[NicoleJohnson]

Are you sure the smaller device modes are not applicable?

Just to be clear, when you select a size from the drop-down, you're not designing for that size specifically. You're designing for the device and can optionally view it at any of those sizes. The "devices" themselves are really just pixel ranges from large to small. At no point is it actually checking whether you're on a desktop/laptop, tablet, etc. (You can see this on desktop if you make your browser window half the normal size--your app will then be in "tablet" mode (assuming this looks different from the large device mode) despite not actually viewing it on a tablet.)

I would just approach this as a mobile-first design.