seems not

[color=red]1) It seemed not a bad idea.
[color=indigo]2) It did not seem a bad idea.

Are both of these sentences correct?

It seems that seems can be negated in two ways, doesn’t it?

Gratefully,
Navi.

I would not find (1) acceptable.

If forced to use that construction, I would use:
It seemed to be not a bad idea.
Most naturally, I would use:
It did not seem to be a bad idea.