Why can't I select different sizes on my ecommerce site?

[gptruscelli]

My Size buttons do not allow me to click on them. I try to click M and add to the cart but the size stays small. Someone tried to help me with the code but it was through inspect. I am trying to learn code but Shopify makes it very hard to decipher given they have their own language.

The second photo was the instructions but how do I put it into my website code?

[gptruscelli]

[RobDukarski]

@gptruscelli 

It seems to be working for me. Were you able to get it fixed on your end?

[gptruscelli]

yes thank you