How to create different CSS to multiple blocks?

So I created a survey, it’s a combination of 3 types of questions and total 8 blocks. 
The main type of questions and the end result is shown as below, which are contained 3 text inputs and 1 None option regarding one image or audio. 


The other two types are multiple choice or selective choice. 


The CSS I used below, works for some of the questions but not all of them, sometimes messing up with other types of questions as well.  

************************************************************
.Skin .MC label.q-checkbox {
    display: none
}
.Skin .MC label[for$="~4"] {
    display: block
}
.Skin .MC label[for^="QR~QID3~"] {
    display: block
}

.Skin .MC label[for="QR~QID470~8"] {
    display: block
}
**********************************************************************

Is there anyone know how to create CSS for different blocks? And how do I know which one is the block number as I fail to find the patten from the naming convention for the questions label? 

Thanks.