When Ice first appeared in Justice League International #12 (February 1988), she had a very skimpy costume that looked like this:
Technically, this costume first appeared earlier on Icemaiden of the Global Guardians, but there are some out-of-universe, continuity-finagling shenanigans at play there that aren't germane to this article. Her Wikipedia page goes into detail, if you're curious, however.
Anyway, she eventually changed her costume to the VERY 80s one seen here, which debuted in 1989 (I can't find a specific issue) and became her iconic one. She had a few others here and there, but this is the one she'd always return to.
In 2004, Ice made the first of many Justice League Unlimited appearances in the series premiere (July), and her costume design split the difference. It was mainly her classic one, but with a keyhole and bare arms to suggest the sexiness of the first one.
She would stick with her classic one in the comics whenever she appeared...that is, until Justice League: Generation Lost #18 (January 2011), where this costume showed up. As you can see, it's essentially her JLU one but with a filled-in keyhole and the stripes' colors inverted.
She kept that costume for a while in the New 52, which was a smart move. It's a good one.