When importing CSS with Sass, you need to be a little careful.
Specifically, when using @import, if you include the extension in the file name, it will be imported as a URL. For example, if you use @import "top_firstview.css";, it will be interpreted as a URL.
On the other hand, if you omit the file extension from the filename, Sass interprets it as an inline import. Thus, writing @import "top_firstview"; would insert the contents of the top_firstview.scss ( or .sass) file directly into the current file.
Keep this difference in mind, as it can be especially important on larger projects.