What is relevant evidence in a civil case?

"'Relevant evidence' means evidence, including evidence relevant to the credibility of a witness ..., having any tendency in reason to prove or disprove any disputed fact that is of consequence to the determination of the action." ( 210.) "A trial court has broad discretion in determining relevancy, but it cannot admit evidence that is irrelevant or inadmissible under constitutional or state law. [Citation.] 'The proponent of proffered testimony has the burden of establishing its relevance .... [Citations.] Evidence is properly excluded when the proponent fails to make an adequate offer of proof regarding the relevance or admissibility of the evidence. [Citations.]'" (People v. Blacksher (2011) 52 Cal.4th 769, 819-820.)