Anyone?

[Lynne]

<if condition="$referrals == 0">
<span style="color:red;"> Referrals: 0</span>
<else /> 
<if condition="$referrals <= 19">
Referrals: $referrals
<else /> 
<span style="color:blue;"> Referrals: $referrals</span>
</if> 
</if>

Not tested.