1. open up a CSS file, or create one.
or any selector which is similar in syntax.
3. check validation.
This is a valid CSS3 selector, although aptana studio 3 says it isnt. Can we alter the validation so it includes this?
W3C spec states:
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.
Screen shot included
Attribute selector values inside a :not() argument do not validate. For example:
< does not validate although it should.
Aptana Studio doesn't seem to like the [controls] as an argument, although [controls] means any audio element with the controls attribute. This is perfectly valid. - Please see (w3c) link above.
I've included a second screen shot for this too.