<p>JSF is setting the ID of an input field to <code>search_form:expression</code>. I need to specify some styling on that element, but that colon looks like the beginning of a pseudo-element to the browser so it gets marked invalid and ignored. Is there anyway to escape the colon or something?</p>

<pre><code>input#search_form:expression {
  ///...
}
</code></pre>

Backslash:
```
```
input#search_form\:expression {  ///...}
```
```
See also
Using Namespaces with CSS
(MSDN)