I am learning php and html at the moment and I thought I will do some work and create something. I created a page called website.php but only put HTML into the file and ran it on my local web server (MAMP). Everything was working fine until I decide to play with the CSS a bit and change the colours. I changed the colours but it wouldn't appear when I am viewing it in my browser. My questions is, does a pure HTML file not work under the .php extension? While everything works, when I changed its colours, it wouldn't change and I had to change it back to .html before it works. However, I know that you can use HTML in php files without any problems.
Another thing was that the hover selector did not work when I used the .php extension and worked with no problems when I changed it to the .html extension. Can someone explain what is going on?