The CA Fair Pay Act makes it illegal to pay an employee less money because they are a woman. However, neither the CA Fair Pay Act nor any other state or federal law make it illegal to pay an employee less for reasons not related to "protected traits," such as gender, race, or religion. Employers have no general obligation to be fair or to treat all employees the same. An employer is free to pay an employee less than another for the same work based on less experience with the organization.
If you were going to sue here, what you would need to prove is that the real reason you were offered less pay was NOT because you are less experienced with the organization, but that this was simply a fabricated pretense to cover up the fact that they wanted to pay you less because you are a woman. You would bear the burden of proving this.
Although it is illegal to retaliate against an employee who sues for gender discrimination, lawsuits for understandable reasons tend to be extremely destructive to employment relationships. So, if you see long term potential with this company, it would really make very little sense to sue or even threaten to sue unless you had compelling evidence that age was actually the motivation here. Otherwise, the decision may be unfair, but it is likely in your best interest not to assume an aggressive posture over it.
I hope that you find this information helpful. Please do not hesitate to let me know if you have any questions or concerns regarding the above and I will be more than happy to assist you further.
If you do not require any further assistance, please be so kind as to provide a positive rating of my service so that I may receive credit for assisting you. Very best wishes moving forward.
* Disclaimer *
Just Answer is a venue for informational and educational purposes only. No attorney-client relationship is formed by these communications.