Hey guys, 

I have another weird one. I'm trying to change the font size of a lightning:radioGroup. So I created a class, and added the class to my Radio Group. It picks the change to "bold" but the font size doesn't change. Instead the spacing between the buttons change. What am I missing? 

SN: Went I apply this class to a paragraph element it works as intended. it only doesn't work on the lightning:radioGroup. 

Comp

<aura:component access="global" implements="lightning:availableForFlowScreens">
    <aura:attribute name="UploadFiles" type="Boolean" default="false"/>
    <aura:attribute name="Encoded_ID" type="String" />
    <aura:attribute name="radioOptions" type="List" default="[
      {'label': 'Yes' , 'value': 'true'},
      {'label': 'No', 'value': 'false'} ]"/>
                <div class="test"><p>This is top level Paragraph elements</p></div>
			<lightning:radioGroup class="test" aura:id="UploadFiles" 
                        name="UploadFiles" 
                        label="Click here to upload any logos, pictures, or other files you would 
                        like incorporated in your design:" 
			options="{! v.radioOptions }" value="{! v.UploadFiles }" />

                <div class="slds-p-top_small"></div>
            

                
            <!-- If customer clicks yes to upload files show the file upload iframe. -->
            <aura:if isTrue="{! v.UploadFiles }" >      
            	<iframe src="{!'/TVA_CFB__RequestFile?'+v.Encoded_ID}" height="325px" 
                width="325px" frameborder="0" class="slds-p-bottom_small"/>                                                                                                                             
            </aura:if>
</aura:component>

CSS class

.THIS.test{
font-size:20pt;
font-weight: bold;
}

Result with CCS applied