how can I change css of a div displaying some text on my home page from the admin are. I want when I enter a color code in my plugin admin page, the code is updated in the c
You should actually not use a .css file and instead use a .php file acting as a .css file. Then you can just set the new color to a variable in the .php css file.
Rename your style.css file to style.php, then add the following to the top of the file:
This line tells the browser that the file is CSS instead of HTML. In your HTML files, change the stylesheet references from style.css to style.php. For example:
citation: http://www.barelyfitz.com/projects/csscolor/