NOTE: This feature is also supported in WordPress and PHP.
Code tag will allow you to add raw code/script within the PSD Text Layer contents. You can draw any paragraph text layer in your PSD, but you should try to keep the size and position of your code layer relative to your design.
Using External Files
Testing the PSD
Use Exports views to render the website with the Fixed Menu enabled. When you scroll the content, the top menu will remain in its fixed position while you scroll.
Using Exports View
Export the PSD in your required environment to see how shapes are rendered in your output.