#portfolio { width:100%; margin:20px 0px; overflow:hidden;}
.tile { float:left; height:auto; width:24%; margin-left:1%; margin-bottom:1%;}
.tile:hover { opacity: 0.5; }
.tile a{display:block; border:1px solid #e2e2e2; box-sizing: border-box;}
.tile a img{width:100%; height:auto;}
/*
.album { background:#00C5CD;}
.ost { background: #CC3232;}
.etc { background: #ddd; }
*/
.category{display: flex; flex-direction:row; justify-content: center;}
.category p{ padding:10px; text-decoration: none;text-transform:uppercase; color: #333; display:inline-block;}
.category p:hover { cursor:pointer; background: #333; color:#eee; }



/* contents */
.headline{ margin-bottom: 75px }