Hi Stesi 
Of course! you can change quite a lot.
You just need to select the date picker element in the Layout menu in the left and then you will have options to style it.
You can also toggle the advanced menu in the “Style” subsection where you can see even more options.
In my photo you can see I changed all colors, added a lateral menu with an icon, rounded the corners of the calendar, changed the padding.
For more information on this element visit the docs: Date pickers | Documentation