Kevin Costner Wears All White To Divorce Deposition With Estranged Wife Christine

Kevin Costner appears to be making a statement at his divorce deposition ... showing up in all white.

The "Yellowstone" star casually strolled into Saturday's depo in Santa Barbara in an all-white ensemble, keeping it cool behind some dark sunglasses and leaving the top of his dress shirt unbuttoned.

Kevin's sitting down to answer questions under oath about his divorce from estranged wife Christine Baumgartner ... and he's got his lawyer, Disso Queen Laura Wasser, in his corner.

Christine was quite the opposite on her way into the depo ... wearing a red blouse and dark slacks, with a couple fancy bags.

She was actually scheduled to arrive for her deposition after Kevin, but she showed up about a half hour before him ... and it looks like she means business.

Remember ... Kevin and Christine's divorce has gotten extremely contentious.

Most recently, Kevin's lawyers slammed Christine over their prenuptial agreement ... as there have been some signals she's going to contest the prenup on grounds she didn't understand what she was signing.

It's a good bet Wasser is going to grill Christine over the prenup ... and there's a lot on the line for Kevin's estranged wife.

If Christine challenges the prenup and the judge enforces it, she will have to return the $1.5 million Kevin already fronted her, plus pay his attorney's fees.