For the all the three colors you can have the size you prefer among regular, large and extra large. And, of course, you can select the colors of three types of button on the admin panel.

[ pix_button type="first" size=""]Button[ /pix_button]

First color regular

[ pix_button type="second" size="large"]Button[ /pix_button]

Second color large

[ pix_button type="third" size="extra"]Button[ /pix_button]

Third color extra-large