body,html{height:100%;}

#body_html{}
#body_main{position:absolute; left:50%; top:50%; width:300px; margin-left:-150px; margin-top:-72px;  text-align:center; }
#body_main .body_text{text-align:center; font-size:40px; padding-bottom:10px; color:#777}
#body_main .body_self_jump{font-size:18px; color:#ff6f00;padding-bottom:10px;}
#body_main .body_self_jump span{color:#f00}
#body_main .body_jump{padding:4px 16px; background:#ff6f00; display:inline-block; border-radius:4px; color:#fff; cursor: pointer;}