Rotating Font Awesome icons

Howdy, LOVE this plugin. I have probably a very basic question about using Font Awesome characters as per your instructions on your blog. This CSS works great:

.collapseomatic.fa-triangle {
background-image: none;
}
.collapseomatic.fa-triangle:before {
font-family: FontAwesome;
content: “\f0da”;
color: #6e9846;
font-size: 1.6em;
line-height: 0.5em;
font-weight: bold;
padding-right: 0.5em;
}
.colomat-close.fa-triangle {
background-image: none;
}
.colomat-close.fa-triangle:before {
font-family: FontAwesome;
content: “\f0d7”;
}

but I would prefer to use the “fa-play” character (\f04b) instead of the fa-caret-right (\f0da), and for the close, instead of the fa-caret-down (\f0d7), I want to rotate the play character so it points downward. I can’t figure out how to set that in the CSS above, i.e. where to put the “icon-rotate-90”. Is that possible to do in CSS? I tried using transforms but that had no effect. Thanks for any info you can provide.

The page I need help with: [log in to see the link]