It has got nothing to do with not drinking enough water.
It’s the B-complex vitamins in the multivitamin. Most of the stuff in multivitamins just comes out the other end in excess, just we can see the evidence of this one.
If you have your multivitamin at night, usually just the first time you pee in the morning will be bright yellow, then more normal through the rest of the day. If you take it during the day, it might be a yellow for a few pees.
If you want to check that it’s not the multivitamin, just take mama’s advice.
As long as you keep taking it, you will experience this. Drinking more water just dilutes the colour, it’s not gonna help you absorb more B vitamins.
sigh
actually if you dont drink enough water (with or without taking vitmains) your urine will be yellow.
In this case…its most likey the cause of vitamins…but even then as u said drinking more water will dilute the color.