Good Day All,

I created a custom page using HTML/CSS/JS and when testing everything works smoothly in the browser. The problem is how can I load this into a SharePoint (Classic) page?

I have the JS inside the HTML file and when I load just HTML page with the basic js it renders fine in SharePoint and works fine, just isn't styled.

However, when I load in the CSS, SharePoint goes bonkers and the sidebar and topbar/editing buttons all go crazy and become messed up. I then have to delete the html file from the SharePoint library to get the SharePoint page back to normal.

I thought maybe the CSS was attempting to be applied to whole page so I got rid of any generic css stylings like "table" "div' etc. and switched all css to classes and ids to avoid any unwanted applications but it still breaks the page.

I have never had to load code into a SharePoint page before so I am not sure if it's possible or what the best practices are.

Any help or insight is greatly appreciated!