This pure CSS CTA microinteraction for a button was designed by Daniel Gonzalez. You have 2 small circles hovering the text and when you move the move over it, they expand to form a layered background for the text effectively converting it into a button.
If you are having trouble with the pen, try the archived copy on GitHub
Attention Grabbing Button Snippet
See the Pen UI Button Hover Effect #2 by Daniel Gonzalez (@dan10gc) on CodePen.0