10knotes: Which gray box is darker? Maybe you think that it’s the top one, but you’re wrong. They have the same color. Try covering the line between them. You’ll see. I bet your finger is in your monitor now… (Nat-Geo) Submitted by
tags: 10knotes.1000notes.com
original: https://a-f-r-g.tumblr.com/post/13039344503