<imgthe literal text <img (case sensitive) .+?any character (except for line terminators), repeated at least once
class="the literal text class=" (case sensitive) .*?any character (except for line terminators), repeated any number of times
redthe literal text red (case sensitive) .*?any character (except for line terminators), repeated any number of times
"the literal " (3410 / 428 / 2216)
g modifier: global. Finds all matches instead of stopping after the first