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Ignore case sensitivity in a CSS attribute selector

Written byPhuoc Nguyen
23 Mar, 2021
By default, CSS attribute selectors are case-sensitive. It means that `a[href$=".png"]` has effect with the links whose extensions are `.png` only.
Imagine that you're building a files management application. It would add an icon to a file based on its extension. For example, the following CSS inserts an icon to any `.png` file.
a[href$='.png']:after {
content: url(/assets/png.svg);
In reality, the files are uploaded by the users and we can't control the file extensions. A png file can be named as `.png`, `.PNG`, `.pNG`.
In order to accept all of these variants, we can add `i` right before `]` in the selector.
a[href$='.png' i]:after {
content: url(/assets/png.svg);

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Phước Nguyễn