Strong Acid/Strong Base Titration
http://antoine.frostburg.edu/chem/senese/101/acidbase/indicators.shtml
This is a link to a webpage that talks all about pH indicators and the different pH ranges if you're looking for more info.

When it comes to your question, the color should go from yellow to green because in your breaker is where you add the indicator fluid and HCl acid and you titrate that with the NaOH base. If you titrate further than your green color you have now made your solution more basic.