Hide Panels- Multiple conditions rule

Hello, 

I'm having a bit of trouble working on hiding panels depending on the selection of a drop down. The drop down has several codes which will populate a section (hidden panel).

This is how to the form is supposed to work: User selects a code from first drop down, second drop down populates a lit of codes associated with that first drop down selection. When a code is selected from second drop down the associated panel should show. 

This is the rule i'm using but it doesn't seem to work: 

CodeType(is the selection from the second dropdown)

CodeType=="Code_1" || CodeType=="Code_2" || CodeType=="Code_3" || CodeType=="Code_4" || CodeType=="Code_5" || CodeType==""

Can someone point me in the right direction on how to accomplish this? 

Thanks in advance