html{
 background:#000;
 scrollbar-arrow-color:#707070;
 scrollbar-base-color:#000;
 font-size:12px;
 color:#707070;
 margin:0px auto;
}

body {
 margin:auto;
}

/*インデックス*/
#main_1{
 position:absolute;
 top:50%;
 left:50%;
 width:750px;
 height:423px;
 margin-top:-211px;
 margin-left:-375px;
}