CSS Instance Tutorial: Semicolon causes page clutter

Yesterday because of a page CSS style increase, need to add the original CSS inside the style.

Because of the addition of some changes in the head, so, the top of the style sheet modified a bit!

The top of the original is:

@charset "Utf-8";

Later, after I added something,

and put this:

@charset "Utf-8";

Put it on the top.

But accidentally removed the semicolon, and became like this:

@charset "Utf-8"

The resulting page has styles that are not applied.

Baffled, and finally uploaded back to the original backup style, all OK.

Suddenly thought yesterday seemed to delete this semicolon, so add again upload, everything ok!

I am too careless to make this mistake again!