Daily Chinese Idiom Guessing Game
To click with someone immediately; to be in tune right away.
拍乐曲的段落，也称打拍子。一打拍子就合于乐曲的节奏。比喻困情意相投或有利害关系，一下子就说到一起或结合在一起。
清·李绿园《歧路灯》第十八回古人云‘君子之交，定而后求；小人之交，一拍即合。’”
They met at the conference and found they agreed on everything; they just clicked.