Css驗證器給出了不允許的錯誤

Question

我正在使用validator.w3.org並出現錯誤。爲什麼這個錯誤發生在 css？任何人都有建議去除這個錯誤。

Line 1, Column 1: character "*" not allowed in prolog 

Line 20, Column 2: character "m" not allowed in prolog 
**m**argin: 20px 0 0 20px; 

Line 31, Column 2: character "b" not allowed in prolog 
**b**ackground-image: -webkit-gradient(

Line 57, Column 1: character "{" not allowed in prolog 

Line 113, Column 2: character "w" not allowed in prolog 
width: 90px; 

Line 133, Column 2: this is not an SGML document 

Answer 1

validator.w3.org是標記文檔（XML，HTML等）的一個驗證。

驗證CSS使用https://jigsaw.w3.org/css-validator/。