test

/*test*/
*{ margin:0; padding:0; font-size:12px; font-family:Verdana, Arial; line-height:1.8; list-style:none;}
#info,#nav{ margin:50px; border:1px dashed #f30; background:#ffc; padding:50px;}
#info div{background:#f00; width:0px; height:0px; overflow:hidden; margin-bottom:10px;}
/*测试*/
#com_a{ border-top:10px solid #ffc;border-left:10px solid #f30;border-bottom:10px solid #ffc;}
#com_b{ border-top:10px solid #ffc;border-right:10px solid #f30;border-bottom:10px solid #ffc;}
#com_c{ border-top:10px solid #ffc;border-right:10px solid #f30;border-bottom:10px solid #ffc;border-left:10px solid #f30;}
#com_d{ border-top:10px solid #f30;border-right:10px solid #ffc;border-bottom:10px solid #f30;border-left:10px solid #ffc;}
#com_e{ border-top:10px solid #ffc;border-left:10px solid #f30;}
#com_f{ border-top:10px solid #f30;border-right:10px solid #ffc;border-left:10px solid #ffc;}
#com_g{ border-right:10px solid #ffc;border-bottom:10px solid #f30;border-left:10px solid #ffc;}
#com_h{ border-top:10px solid #f30;border-bottom:10px solid #f30;border-left:10px solid #ffc;}
#com_i{ border-top:10px solid #f30;border-right:10px solid #f30;border-bottom:10px solid #f30;border-left:10px solid #ffc;}

测试