I am having an issue with a calcite component conflicting with a sidebar. The sidebar overlays itself on top of the calcite component dropdown, even with overlayPositioning set to fixed. I have tried adjusting the z-index of the pop-up itself, and suspect that may be the solution, but have been unsuccessful so far. The area below the sidebar's bottom cannot be used either.

The app in question must remain in the sidebar, as the arrow allows the user to expand to see advanced options. The date picker is defined as:
<CalciteInputDatePicker className='date-picker' overlayPositioning='fixed'/>
Any help would be much appreciated! Thank you!