You probably need to see the screen smaller. Back away from it, or reduce the size of your browser window.
I've been doing stuff like this since I was a kid; the first time I remember was staring at the tiled floor in the school bathroom. The tiles were one-inch, and I noticed that there was an illusion of the floor being nearer to my face if I looked at my knees.
Practice on the 3D youtube videos sometime. They have cross-eye and wall-eye (uncrossed eyes) viewing modes.
Oh man this would be hard to explain...hmm...your creating a left and right image. Basically what each eye would see. In the left image you shift everything to the left and in the right image everything is shifted to the right. Now how far you shift the objects does dictate how 3D it will appear. a slight shift will be slightly 3D in appearance. A large shift will appear more 3D