The clauses are not "illegal" but are subject to negotiation. If this is a serious, potentially long term commitment, an hour or two with an attorney, to discuss issues like "work made for hire" and other IP and employment issues, would be worth the expense.
The above is general legal and business analysis. It is not "legal advice" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in California. See also avvo.com terms and conditions item 9, incorporated as if it was reprinted here.
The contract needs to be analyzed by an employment law attorney to determine whether the "continuing obligations" and other clauses are unlawful, etc. For example, if there is a noncompete clause, those are invalid in CA.
The provisions are not illegal. The employer may have included them to help protect against the possible theft of trade secrets.
You are certainly free to negotiate and propose modifications of these provisions, or even to ask that they be stricken completely. You can also ask your proposed employer directly why it has included these provisions.