Phone and email size in header

Hi guys,

How can I increase the size of the phone number and email in the header?
I tried the adding the following css to the Custome CSS under Fortuna Options but it didn’t seem to have any effect:

.header_phone {
font-size: 20px;
}

.header_email {
font-size: 20px;
}

Is there a better way of doing it?

Speak soon,

Chris