This one is tricky, how can you make your background color and font color customizable for your visitors? Well I have made a sample in this project: User defined CSS Website: Demo using PHP and AJAX, where any user can use slider to customize the web page CSS properties particularly the background color and the font color.
Here is the overall principle of operation:
1. Users will decide the best color combination of background and font color.
2. Visitors will then click “Customize webpage color”.
3. CSS settings will then be sent to the server using AJAX. The purpose of AJAX is to avoid page reload that can distract user experience.
4. PHP will then analyze the input and output corresponding CSS based on the user request.
5. Once the CSS has been updated on the HTML, the background and font colors will then be updated.
You can try downloading the files and test it in your own server.
