The underline should be removable adding the property in yellow below
a.mytop, a.mytop:hover {text-decoration:none !important;}
Not sure by what you mean by the icon should be thinner. This is a font icon, what you can do is:
- Make it bigger or smaller using the font-size
- Put more space around it using padding
- Make it thinner using font-weight (100,200,300,400,500,600,700,800,900)
If you want me to see your changes, I need you to clear ALL caches after making changes