Question

Is there a feminine and masculine version for "inteligente"? I'm just very curious.

Answer 1

The word itself is a masculine word so no there is no feminine version. But it is to be used freely between the two, that is just the way it is grammatically used.

Answer 2

If the word ends in an "a" then it is feminine. If it ends in an "o" then it is masculine. 
EX: 
disordenad(a) - feminine 
disordenad(o) - masculine 

To make an inanimate object masculine, the person you're describing has to be a boy. To make the object feminine, the person you're describing has to be a girl. Same with personality. 
EX: 
Ella es disordenada. 
El es disordenado. 

Some words don't have a masculine or feminine form. if a word ends with an "e" than that means it doesn't have a masculine or feminine form. 
EX: Inteligente. It doesn't end in an "o" or "a" therefore, it is can be used as either masculine or feminine. 

EX: 
El es inteligente. 
Ella es inteligente.