"It does not suit you."
Translation:Це вам не пасує.
Тебе is the accusative case, used for the direct object.
Тобі is the dative case, used for indirect object (it often corresponds to English 'to you').
Generally, direct objects are affected by the action more strongly than indirect objects. Here's an example:
- Я покажу тобі світ. 'I'll show you the world.' 'The world' is the direct object, 'you' is indirect object.
- Я покажу тебе світу. 'I'll show you to the world.' 'You' is the direct object, 'the world' is indirect.