Event widget – remove vertical spacing

Hi
I am trying to remove the vertical spacing from my events widget, see http://www.giffnocknorth.co.uk right hand widget area. I have identified the css and using the jetpack css editor pasted the following –

.tribe-events-list-widget ol li {
  /* margin-bottom: 30px; */
  list-style: none;
}

Thus removing the bottom margin, which works in Chrome Inspect Element but has no effect when added to the css editor.

Id be grateful for some guidance as to where i am going wrong.

Thanks in advance