Why can't semicolon be inserted through javascript style attribute?

Question

I tried changing bcakground bodyto javascript and noticed that the following does not work:

document.body.style.background = "#000;"  

But if I omit the semicolon, then it works:

document.body.style.background = "#000"  

Why is that? Isn't there #000;still a line?

Answer 1

;not part of the meaning. This is a style separator.

selector {
    styleName: styleValue;
    /* Separator --------^----- */
}

From specification :

A rule set (also called a "rule") consists of a selector, followed by a declaration block.

({) (}). (;) .

( ;) . , #000; , .

Answer 2

# 000; : # 000;; css