The images I used for the layout are from three different volume, and this is a circumstance, not a chose! XD
The first one in the header came from an insert color page of the 2nd Volume, and the other one is from the Cover of the third volume. This last image is my favuurite and I always thought this layout in different modes but with this cover! 
The last Eco in the footer is from the first volume, where Belca escaped from the home in which Eco was taking care of him. He's too cute and I love that expression, so I coloured it with my hands!

The main colour is green because I link it to Eco. It's perfect to him, isn't it? This is the reason why I realized even the codes with this colour.