BuddyPress.org

You just need to apply the styles from #megamenu to `body div#wp-admin-bar .padder` to start off and copy over the block_top.png from megamenu to your theme’s /images/ folder
`body div#wp-admin-bar .padder {
border: 1px solid #000000;
border-bottom: none;
background-color: #333333 !important;
background: #333 url(images/black_top.png) top left repeat-x;
background: -webkit-gradient(linear, left top, left bottom, from(#333333), to(#111111));
background: -webkit-linear-gradient(top, #333333, #111111);
background: -moz-linear-gradient(top, #333333, #111111);
background: -ms-linear-gradient(top, #333333, #111111);
background: -o-linear-gradient(top, #333333, #111111);
-webkit-border-radius: 2px;
-moz-border-radius: 2px;
border-radius: 2px;
-moz-background-clip: padding;
-webkit-background-clip: padding-box;
background-clip: padding-box;
-webkit-box-shadow: inset 0px 1px 0px 0px rgba(255, 255, 255, 0.1);
-moz-box-shadow: inset 0px 1px 0px 0px rgba(255, 255, 255, 0.1);
box-shadow: inset 0px 1px 0px 0px rgba(255, 255, 255, 0.1);
}`