Removing Border White Line

hi 

How do i remove those white border line in the header? Thanks a lot

Here are my code.

  <style>
div.RadPanelBar_Default div.rpHeaderTemplate,
div.RadPanelBar_Default a.rpLink,
div.RadPanelBar_Default a.rpSelected
{
    background-image: none;
    background-color: #2C3E50;
    color:#fff;
    border-color:#2C3E50;
    border: none 0px !important; 
    font-size:medium;

}

 div.RadPanelBar_Default .rpExpanded {
    background-color: #2C3E50 !important;
    color:#fff;
    border-color:#2C3E50;
    border: none 0px !important; 
}  

 .RadPanelBar .rpRootGroup, .rpItem .rpLink   
{    
     border: none 0px !important;    
     color: #FFF;  
     text-decoration: none;  
     border-bottom-width: 0px !important; 
     padding: 0px 0px 0px 0px !important; 
}  

.RadPanelBar rpRootGroup  .rpGroup .rpItem .rpLink
   {
      color: Green;
   }
.RadPanelBar .rpOut  
{  
    border-bottom-width: 0px !important;  
}  
.RadPanelBar_Default ul li a:link, 
.RadPanelBar_Default ul li a:visited, 
.RadPanelBar_Default ul li a:hover, 
.RadPanelBar_Default ul li a:active 
{
    color: #fff;
    display: block;
    /* width: auto !important;
    float: left; */
    border-top: 0px solid #2C3E50;
    border-bottom: 0px solid #2C3E50;
    border: none 0px !important; 
 

}
.rpExpanded {
    background-color:#2C3E50  !important;
    color:#fff;
    border: none 0px !important; 
}
 
.rpSelected {
    background-color:#2C3E50  !important;
    color:#fff;
    border: none 0px !important; 
}

 
</style>
    <telerik:RadPanelBar ID="RadPanelBar1"  runat="server">
          
    </telerik:RadPanelBar>