.button {
/*position: relative;*/
display: inline-flex;
border: 2px solid;
border-radius: 10px;
/*width: 338px;
height: 150px;*/
background-position: center;
background-size: cover;
height: 105px;
width: 50%;
margin-left: auto;
margin-right: auto;
-webkit-transition: all .7s ease-in-out;
-moz-transition: all .7s ease-in-out;
-o-transition: all .7s ease-in-out;
transition: all .7s ease-in-out;
}

.youmu {
background-image: url(img/youmu1.png);
}
.youmu:hover {
background-image: url(img/youmu2.png);
}

.music {
background-image:url(img/music1.png);
}
.music:hover {
background-image:url(img/music2.png);
}

.tools{
background-image: url(img/tools0.png);
}
.tools:hover {
background-image: url(img/tools2.png);
}

.cosplan{
background-image: url(img/cos0.png);
}
.cosplan:hover {
background-image: url(img/cos2.png);
}

.gallery{
background-image: url(img/gallery1b.png);
}
.gallery:hover {
background-image: url(img/gallery2b.png);
}

.danmaku{
background-image: url(img/danmaku1.png);
}
.danmaku:hover {
background-image: url(img/danmaku2.png);
}

.promo {
  background-image: url(img/shop_openh.jpg);
  background-image: url(img/shop_open.jpg);
  width: 350px;
  height: 350px;
  margin: 10px;
}
.promo:hover {
  background-image: url(img/shop_openh.jpg);
}