1 – Extrait de https://www.w3.org/TR/selectors-3/#attribute-substrings
« Substring matching attribute selectors
Three additional attribute selectors are provided for matching substrings in the value of an attribute:
[att^=val] Represents an element with the att attribute whose value begins with the prefix « val ». If « val » is the empty string then the selector does not represent anything.
[att$=val] Represents an element with the att attribute whose value ends with the suffix « val ». If « val » is the empty string then the selector does not represent anything.
[att*=val] Represents an element with the att attribute whose value contains at least one instance of the substring « val ». If « val » is the empty string then the selector does not represent anything. »
[…]
Exemples :
The following selector represents an HTML object, referencing an image:
object[type^="image/"]
The following selector represents an HTML anchor a with an href attribute whose value ends with « .html »:
a[href$=".html"]
The following selector represents an HTML paragraph with a title attribute whose value contains the substring « hello »:
p[title*="hello"]
Exemple
*[class^="prefix"] {
color : red;
}