.mv_under{
  background-image: url(../img/portfolio/mv_under.jpg);
  background-size: cover;
  background-position: center center;
  width: 100%;
  height: 450px;
  position: relative;
}

.portfolio{
  width: 1200px;
  margin: 0 auto;
  text-align: center;
  overflow: hidden;
}
.portfolio h3{
  text-align: center;
}
.portfolio_innr{
  display: flex;
  flex-wrap: wrap;
}
.portfolio_flow{
  width: 250px;
  margin-right: 50px;
}
.category{
  border: 1px solid #75B0E0;
  margin-bottom: 20px;
}
.category p{
  background-color: #75B0E0;
  color: #fff;
  padding: 8px 0;
}
.category ul{
  padding: 20px 0;
}
.category a{
  display: block;
  padding: 5px 0;
  color: #333333;
}
.archive{
  border: 1px solid #75B0E0;
}
.archive p{
  background-color: #75B0E0;
  color: #fff;
  padding: 8px 0;
}
.archive ul{
  padding: 20px 0;
}
.archive a{
  display: block;
  padding: 5px 0;
  color: #333333;
}

.portfolio_content {
  /* width: calc(100% - 300px); */
}
.portfolio_content ul{
  display: flex;
  flex-wrap: wrap;
  /* justify-content: space-between; */
}
.portfolio_content ul li {
    width: calc(31% + 1px);
    margin-bottom: 20px;
    text-align: center;
    margin-right: 30px;
}
.portfolio_content ul li:nth-child(3n) {
    margin-right: 0px;
}
.portfolio_content ul li a{
    color: #333333;
}
.portfolio_content ul li img{
  width: 100%;
}
/******************************************************** 第一メディアクエリ設定 */
@media screen and (min-width: 0px) and (max-width: 1200px) {
.portfolio {
    width: 90%;
}
.portfolio_content ul li {
    margin-right: 3.2%;
}

}
/******************************************************** タブレット用設定 */
@media screen and (min-width: 0px) and (max-width: 940px) {
  .portfolio_flow {
    width: 190px;
    margin-right: 0px;
}
.portfolio_content {
    /* width: calc(100% - 220px); */
    order: 1;
    width: 100%;
}
/* .portfolio_flow {
    order: 2;
    width: 100%;
} */
}

/******************************************************** スマホ用設定 */

@media screen and (min-width: 0px) and (max-width: 640px) {
.mv_under {
  background-image: url(../img/portfolio/mv_under_sp.jpg);
  background-size: cover;
  background-position: center center;
  width: 100%;
  height: 400px;
  position: relative;
}
.portfolio_content ul li {
    width: 48%;
    margin-right: 4%;
}
.portfolio_content ul li:nth-child(3n) {
    margin-right: 4%;
}
.portfolio_content ul li:nth-child(2n) {
    margin-right: 0;
}
}