Hard Returns in CSS

I use Psimple 1.0 theme at this site: http://slsailing.com/egypt . Apparently the use of widgets is not standardized in this theme. In the Miscellaneous section Moshu was a big help solving a display error. This related question seems best posted here in Themes and Templates.
To improve the sidebar display of RECENT COMMENTS I would like to put a hard return after each listing. Can you suggest how to do this? Here is the related code from the Psimple style sheet.

/* Left Sidebar */
#inner {width: 180px; float: left;padding: 0px 0px 0px 15px;}
#inner h2 {color: #fff;font:normal 16px "arial black";border-bottom:1px dashed #999;margin:0px 0px 5px 0px;padding:15px 0px 3px 0px;}
#inner ul {list-style: none;margin: 0px;padding: 0px;}
#inner ul li {display: inline;padding: 0px;margin: 0px;font-size:12px;}
#inner ul li a {display: block;color: #fff;text-decoration: none;margin: 0px;padding: 5px 0px 5px 0px;border-bottom: 1px dotted #eee;}
#inner ul li a:hover {background: #718A6E;color: #ccc;}
#inner a.morre {background: #f6f6f0;color: #dd6600;padding:2px 2px 1px 2px;margin:0px 0px 5px 0px;font-weight:bold;border-bottom:none;width:60px;}
#inner a.title {color: #fff;padding:0px;background:none;margin:0px;}
#inner p{padding: 3px 0px 0px 0px;margin: 0px;line-height: 20px;color:#fff;}
#s{width:60%;}