Adding link on product pages

Hello, wanted to see if anyone can help me. I am a novice at this. I want to add a link on my product pages to a size chart. I am using AMBRO within Shopify. The link button is muted so I tried to override it with some html code which didn’t work. Not sure if its the code I am trying to use or that it is being blocked somehow by Shopify. Here is the html that I am using:

 

Size Chart

Any ideas anyone?

Thank you in advance.

LL

Hi,

Contact with your purchase item author @velatheme right here as a comments

Thanks!