How to align sticky block to the right?

I want to right align the sticky block inside the wp-block-colum. I don’t know how to do this when the position is fixed. Is it possible?

I want the max-width of the sticky block to be 300px and want it to be at the end “right” of the parent column, but flex alignment is not working.

I’ve managed to roughly position it with the following CSS, but is there a better way?

`.wp-block-senff-sticky-block {
top: 100px !important;
max-width: 330px;
margin-left: 3% !important;’

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