Update main.scss

[daniel-web-developer]

Removed the option to select text on buttons.

This is a simple change. Particularly, I don't think it's very nice when the text inside buttons is "selectable" and I try to remove this feature in every website I make. I simply added user-select: none and -webkit-user-select: none to some of the main.scss elements to accomplish it.

References: https://developer.mozilla.org/en-US/docs/Web/CSS/user-select