How to edit pfp border?

In the style element of your profile html, add '.profile-pic {border: width display color}' replacing width, display, and color with your desired values. display would be like solid or dotted. this only works for a border of a solid color or gradient. If you want a specific design like a lacy border as you mentioned, youll probably have to add a transparent image of the border you want and position it over your profile picture. 

that's what i use

you can change all the values, like pixel size, color, styling etc

same with the border shadow

<3