Strange visual behavior when selecting a date range

[Alberto-IG]

Hi!
First of all thank you for the template you have made. I've been using Home Assistant for a few months, and almost from the beginning, after trying many, I left yours installed.

I have a question about a visual aspect (although it may only happen to me):

When I am selecting a date range, for example in the History section, only the first and last dates are marked in light blue. Intermediate dates remain very dark.
Is this normal, or as I said before, is it just me?

Thank you very much in advance.

Regards,
Alberto.