Change case in contact form

I see label style value set to uppercase.. which you can change in style.css

#respond label, .post-content form label{
text-transform: none;
}

Right now it is set to uppercase.

I changed it but it shows no difference.
Could you kindly mention precisely the steps to follow ?
Maybe I skipped one…

https://azzurytt.com/wp-content/themes/wp-advocate/style.css?ver=4.4.1

I still see value is uppercase not none

Thank you very much !