決めることに賛成です Ni particle


私としては、多数決で決めることに賛成です。 in this sentence why did we use に particle before 賛成です.
is 賛成 here working as a noun or adjective ?




This 賛成 is a noun known as a [_no-
adjective_](https://japanese.stackexchange.com/q/2770/5010). A no-adjective is
a noun that translates to an English adjective. Unlike ordinary nouns, no-
adjectives and na-adjectives can be modified by adverbs (e.g., やや, かなり, とても)
and adverbial expressions, which includes ～に.

Similar examples:

  * この曲は若者に人気です。  
This song is popular among young people.

  * 若者に人気の曲  
a song that is popular among young people

  * この風習は日本に特有です。  
This custom is unique to Japan.

  * これは日本に特有の風習です。  
This is a custom that is unique to Japan.

賛成 also works as a plain (suru-)verb:

  * 多数決で決めることに賛成します。

