It's a common phrase used to contrast a previous situation with the current one, highlighting a change in circumstances.
Here's a breakdown:
* Mas: This translates to "but" in English. It introduces a contrast.
* Ahora: This means "now" in English. It refers to the present moment.
Example:
* *Antes no tenía tiempo para leer, mas ahora tengo más tiempo libre.*
(I didn't have time to read before, but now I have more free time.)