My question involves landlord-tenant law in the State of: CA

The upstairs neighbors are so loud I can barely have a peaceful moment. I reported this to the landlord over and over again. Now she even mocks my complaints to the other tenants (they have told me). The upstairs neighbors are worse in retaliation. Banging, stomping, pounding, etc even at the crack of dawn and late at night is a regular occurrence.

It does not matter if I hit the ceiling with a broom or yell up at them. When I have knocked on their door (with or without the police), they have just ignored me.

The hardwood floors contribute to the problem obviously although the landlord will of course not admit this since her husband installed the floors.

Often the landlord does not even respond to my complaints. The noise is often constant and even horrifying as more than once it sounded as if violence occurred. These people stay up for days and that concerns me as well, that they are not people to ignite further. However, my quality of life has so depreciated that despite any possible threat I need advice about how to proceed.

What actions can I take? Is the landlord liable in any way? What should I do?