noun which may take the genitive case particle 'no'
perfectly in sync; in step; on the same wavelength
Describes people or groups acting in perfect harmony, timing, or mutual understanding. Often used for dancing, music, teamwork, or close relationships.
二人のダンスは息ぴったりだった。
Their dance was perfectly in sync.
あのチームは息ぴったりの連係プレーを見せた。
That team showed perfectly coordinated teamwork.