Reimplemented all JS features to HTML and CSS

Includes the setting of `target="_blank"` and animations.

I saw that you were applying the same animation to many places, so I grouped them up into two divs and animated them both.

As a side-effect of this, animation-specific styles which were baked in to the CSS (like `position: relative; opacity: 0; top: 30px;`) are now removed, allowing them to be used in other pages where there may not be animations.

And now `index.html` is completely JS free! ^_^