Sample 4
This website has its style and script within the html. And its navbar content are external links because there is no folder content to refer to; no extra pages were created. If what you want is to be able to link pages within a website, then this website's code is not what you need. You need the code of the home-page.
The dark/light mode switcher style is different from the home-page. If you want the home-page, but with this dark/light mode switcher...now you want more, which entails you edit it, or pay a professional web developer/designer.
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