Makes the buttons in the menus blue and translucent. It also tweaks hotbar colors. It also replaces the recipe book texture with a smoother version. That's it. No block changes or item changes. It makes the menus look more modern and for the most part keeps the look and feel of the in-game experience. There's not much to it.
If you are using OptiFine the loading screen will be blue.
You may distribute modifications as long as credit is given and a link is provided to this page.