styles: I can not change the background color value of wp: meta_value of content.xml

I can not change the background color value of

I am trying to change by css the value of the background color in the class that is automatically generated by the named Visual Composer:

vc_custom_1510991353768

with this:

.vc_custom_1510991353768 {
background color: # 006e48! important;
}

But my styles.css According to the reference code below, the subject of the child does not recognize it because it is owned by:


    
    

I already tried this (custom colors for rows of publications based on the meta value of the message), but this does not work for me.

I need help, thanks in advance.