Sticky Bar Display

Hello,

Can you tell me how to put a (-) to the discount checkout amount, how to fix the sticky bar (it eats the header/footer) and how to get a responsive sticky bar? https://prnt.sc/uj96gm

In add: How to display the sticky bar even if the customer doesn’t hit the min cart total? It’s interesting for all of us to display the “missing message” without condition (cart update).

Thank you.