body {
  background-color:#A5FFCE;
  text: #333;
  margin: 0;
  font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
}
.main_top, .main_middle, .main_bottom {
  border: 1px #000 solid;
  width: 750px;
  margin: 10px auto;
  padding: 20px;
  background-color: #fff;
}
.main_bottom {
  font-size: 14px; 
}
@media screen and (max-width: 800px){
.main_top, .main_middle, .main_bottom {
  width: auto;
  margin: 10px 10px;
}
}
.about dt {
  border-bottom: 1px dashed #000;
  font-size: 16px;
}
.about dd{
  font-size: 16px;
  line-height: 1.6;
  padding: 10px 0px;
}
.about dd p{
  font-size: 16px;
}
.backto {
  text-align: center;
  font-size: 16px;
}
.backto a {
  text-decoration: none;
}
.backto a:\hover {
  text-decoration: underline;
}
.contents {
  display: flex;
  flex-wrap: wrap;
  margin: 15px 0px;
}
.item {
  padding: 0px 10px;
  text-align: center;
  width: 140px;
  font-size: 14px;
}
.item img {
  border: 1px solid #666;
  filter: drop-shadow(2px 2px 2px rgba(0,0,0,0.3));
}
.item2, .item3 {
  flex: 1;
}
.item3 {
  font-size: 14px;
}
.a_title {
  font-size: 16px; font-weight: bold;
}
.date {
  display: block;
  font-size: 13px;
  color: #333;
  border-bottom: 1px dashed #000;
  margin-bottom: 10px;
}
.credit {
  display: block;
  font-size: 13px;
  padding-left: 18px;
  padding-bottom: 5px;
}
.youtube {
  position: relative;
  width: 100%;
  padding-top: 56.25%;
}
.youtube iframe {
  position: absolute;
  top: 0;
  right: 0;
  width: 100%;
  height: 100%;
}
@media screen and (max-width: 460px){
.main_top, .main_middle, .main_bottom {
  width: auto;
  margin: 10px 5px;
  padding: 10px;
}
.about dd {
  line-height: 1.5;
  margin-left: 0px;
}
.item {
  padding: 0px 0px;
  width: 100px;
  font-size: 12px;
}
.item img {
  border: 1px solid #666;
  filter: drop-shadow(2px 2px 2px rgba(0,0,0,0.3));
  width: 100%;
}
.item2,.item3 {
  font-size: 14px;
  padding-left: 10px;
}
.date {
  margin-bottom: 5px;
}
.credit {
  padding-left: 13px;
  padding-bottom: 0px;
}
}