Whereas Emo music tends to wrestle the inner demons of personal defeat, loveloss, heartache etc. No, seriously, HC tends to deal with taking action to change things rather than ruminate on that might have been. I guess the main difference is that Emo tends to be backward looking, and HC tends to be forward looking. Old t-shirts, dress shirts etc. Old, thrift shop gear as with all the above.
Floods are totally cool.
Browns, blacks, dark blues etc. The look is retro with an edge. Drew Carey if he wore thrift store stuff. Heavy on soul-searching, hard to mosh to.