1. div{
2. border:1px solid black;
3. height:500px;
4. width:500px;
5. };
6. p{
7. border: 1px solid black;
8. }
9. h1{
10. border:1px solid black;
11. }According to the above code, the style will be applied only to the <div> and <h1> element and not to the <p> element because:
When the above code is interpreted/read by parser , line 5 will throw an error on line 5 since the closing curly brace is followed by a semicolon, which does not comply with CSS syntax , and an unknown syntax at any point stops the parser from reading the following code until it finds a closing curly braces, so line 6 and 7 will be skipped and it will find a closing braces at line 8 , and starts to read fresh code from line 9 , hence style will be applied to <h1> element.
You can find more information about CSS declaration and syntax on : https://drafts.csswg.org/css-syntax-3/#declaration-value-mode
When interpreting a list of declarations, unknown syntax at any point causes the parser to throw away whatever declaration it is currently building, and seek forward until it finds a semicolon (or the end of the block). It then starts fresh, trying to parse a declaration again.