How can I do changes of colour in Material theme?

Hey Everyone.

I was playing with some themes and I found a theme in the plugin gallery named Material Theme. I m really satisfied with the theme. The only problem I have is that I am unable to change the colour. I opened the file manager and changed the colours in the variables but still theres no change.
Can someone tell me how do I change the colour of the homepage.
Like I want to remove this blue and add a red pink gradient. I changed in the styles folder for variables but still it doesnt updates.
I am attaching an Image so someone please help
Regards,

Hi @Moazzam_Khan,

We give some advice for modifying your CSS, this might be of some help here: https://docs.pkp.sfu.ca/designing-your-journal/en/creating-stylesheet ?

-Roger
PKP Team