Have Popover Content match parents width without hardcoding a width?

[sontiO]

Hello, Im stuck on this styling issue but I feel like it should be solvable, does anyone have any pointers or advice for me?
Im trying to build this UI Element:

The trigger for the dropdown is only the right part with the icon in it, the left button does not trigger the content.
I cant figure out how to have the content width match the width of the parent container (the button and the trigger together)

I know radix provides
--radix-popover-trigger-width which I think would solve my problem, but since the width im trying to match is not only the trigger im not sure how to do this. I attempted to wrap it with the Anchor and using w-full on the content:

<Popover.Root>
	<Popover.Anchor className="flex w-full gap-0.5 text-nowrap">
		<Button />
		<Popover.Trigger className="flex w-9 flex-row items-center justify-center">
		    <ChevronDown />
		</Popover.Trigger>
	</Popover.Anchor>

	<Popover.Content
	        className="w-full"
		side="bottom"
		align="start"
	/>
</Popover.Root>

trying this, I end up with this and I cant find a way to match the widths other than hard coding a width:

Thanks in advance for any pointers