I would like to change it so the user is directed to the pop-up calendar in the Configurable list widget

In the Configurable List there is a date selector + a pop-up calender. I would like to change it so the user is directed to  the pop-up calendar (and the pop-up calendar icon a little bitt bigger), something like the screenshot.

I assume it is just a piece of CSS code, could you help me with that one?

I am sorry that I did not understand your query correctly. Could you please elaborate on your requirement to achieve? Do you mean to allow the user only to select the date from the calendar? 

We will wait for your response. Thank you!