Dynamic Checkout Button height and size change

[Ussama1]

Hello people, I am new to this and I have been trying to find any way to do customization to the dynamic checkout button. 
I have Ella Theme, I tried custom CSS but the editor doesn't allow it. then I researched and tried to edit the theme code but whatever changes I made to the component dynamic checkout.css file it doesn't do anything. 
This is how it looks on my website

and this is how I want it to be 

Can someone please help me out? I literally spent 2 days finding a way to do this on my own but sadly I could. I would really appreciate the help.
Thanks

[Moeed]

Hey @Ussama1 

Could you please provide your Store URL and, if applicable, the Password too? Your cooperation is greatly appreciated!

Best Regards,
Moeed