The probability of what? You'll always be able to use this, as it's open source. Even if it somehow wasn't, it's CSS, so you'd still be able to tweak it however

The probability of what? You'll always be able to use this, as it's open source. Even if it somehow wasn't, it's CSS, so you'd still be able to tweak it however you want. I don't understand what the downside is here.