Trying to center digital time on my watch face

[Kaceyr2000]

I have made a watch face with digital 12 hour time.  But single digit times do not center. If I place the double digit number (say 10:00) where it centers, the single digits don't center, they're off to the side (9:00). Is there a code that will exactly center the face whether it's single digit time or double digit time?  I tried writing "center" in the x: line in the styles.css folder but that did not work. I'm new to this, obviously.  

[Gondwana]

Have a look at text-anchor.

[Kaceyr2000]

Thanks, once I understood what start / middle / end meant in regards to the text, I got it.