The Imperial Marines use a Maroon Sunburst Logo (going all the way back to CT). According to GT: Ground Forces, their basic dress/undress uniform has a black single-breasted tunic jacket * with black trousers, all trimmed with maroon. Their parade dress is a maroon single-breasted tunic with black kilt (though black trousers are used in low-g situations).
Their "utilities" uniform (i.e. fatigues) are a black tunic and grey pants w/ black boots.
* Note that some sources from the CT/MT era suggest that the jacket is double-breasted.