for this code:
<ul id="weird"><?php wp_list_pages('title_li=&child_of=&sort_column=ID&sort_order=asc'); ?></ul>
possible css example:
ul#weird li { list-style:none; float:left; width:160px; margin-right:20px; }
ul#weird li a { font-size:20px; display: block; padding-bottom: 5px; border-bottom: 5px solid #aaa; }
ul#weird ul li a { font-size: 18px; color: #ddd; border-bottom: none!important; }
ul#weird li.page-item-143 a { border-bottom: 5px solid purple; }
ul#weird li.page-item-174 a { border-bottom: 5px solid orange; }
ul#weird:after { content:'.'; display:block; clear:both; visibility: hidden; }