During my 20 min meditation, my visualisations were in blue colour and then changed to purple. Has this happened to anyone else?

The last few weeks I have been feeling a bit sad. The night before I dreamt a happy joyful dream about my deceased father (20 years since), and it gave me lots of positive energy.

Last night I wanted to continue and listened to one of Tara's 20min meditation.

During my meditations, I allow my visions or thoughts to float freely. Suddenly, it all went blue. Everything I saw playing in my had was in blue. It was interesting, like it was a bit aquatic blue to my visualisations.

Then after that they morphed into a dark purple colour. I just allowed it thought I was aware of the sudden colour changes.

Any ideas what happened? Has it happened to you?

I didnt have any specific feeling but felt extremely relaxed.