styles/prosilver/theme/colours.css
Find
border-bottom-color: #368AD2;
Replace With
/* border-bottom-color: #368AD2; */
Find
background-color: #D0E4F6;
Replace With
/* background-color: #D0E4F6; */
Open
styles/prosilver/theme/link.css
Find
border-bottom: 1px solid transparent;
Replace With
/* border-bottom: 1px solid transparent;*/