livedoor相互RSSの質問です

http://www.akb48matomemory.com
上記のｻｲﾄの相互RSSのように一行ずつ線を追加したいのですがいくら調べても皆目検討つきません｡
下記が自ｻｲﾄのRSSのCSSです｡どなたか知恵をお貸し下さい

.rss-blogroll:after {
content:".";
height:0;
clear:both;
display:block;
visibility:hidden;
}
.rss-blogroll {
zoom:100%;
border:2px solid #b0b0b0;
margin-bottom:10px;
padding: 3px 0;
}

.rss-blogroll .blogroll-channel{
margin-left:5px;
width:570px;
height:284px;
overflow-y: scroll;
float: left;
font-size: 12px;
padding:0 0 0 0;/*追加*/
margin-bottom:0;/*追加*/
}

.rss-blogroll .blogroll-channel .blogroll-list {
list-style-type: none;
line-height: 1.3;
font-size: 14px;
border-bottom: 1px dashed #c2c2c2;
padding: 3px 0;
line-height: 1.3;
padding-top:0;/*追加*/
text-decoration: underline;
}

.rss-blogroll .blogroll-channel .blogroll-list a{
padding-left: 5px;
text-decoration: none;
}
.rss-blogroll .blogroll-channel .blogroll-list a:hover{
text-decoration: underline;
}

.rss-blogroll .blogroll-new-entry{
color: #ff0a00;
font-size: 11px;
font-weight: bold;
}
.blogroll_wrapper {
width: 100%;
overflow-y:scroll;
background-color: #FFFFFF;
}
.blogroll_innner {
width: 50%;
height: 300px;
float: left;
}

li.blogroll-list {
border-bottom: solid 1px;
}

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