Set quantity – theme issue

Hello there, i hope i dont bother you, but i have a small issue with my theme, maybe you can assist me here.
Some products have the possibility to set the quantity, like you can add more than 1 SSD or HDD. You are able to set more with the arrows but its mest up.

This is how it normally shows on all my products: https://ibb.co/f1x0td4
And this is how it looks in your Plugin: https://ibb.co/bgXH0sz

Then i corrected the width with CSS to 50% to show better: https://ibb.co/rvrMtss

But still it shows not professional and i am not happy. Can you try with CSS to make it like my theme https://ibb.co/f1x0td4 ? I would be very thankful if you would be able to fix that. I tried with my CSS skills (noob) but i was not able to do anything!

Thank you