Moesia Title widget decoration hide

I am using the Moesia theme on a website being developped (offline for now).
I would like to hide the decorative lines (====) below Services category or the Call to action text.
I tried to add below custom CSS with no success :

h3.widget-title::after {
    color: transparent;

Any idea for the correct syntax ?

Hello there,

Thank you for contacting us about our theme Moesia. I am happy to help with your queries.

Please try this CSS code:

    .so-panel section .widget-title:after {
      display: none;

aThemes Support