.page-lower #visual {
  background: url("../images/sdgs/visual-bg.jpg") center center /cover no-repeat;
}

#main .list {
  display: flex;
  flex-wrap: wrap;
}
#main .list .item {
  width: 18.5185%;
  margin-left: 1.851875%;
}
#main .list .item:nth-child(5n+1) {
  margin-left: 0;
}
@media (max-width:768px) {
  #main .list .item {
    width: 32%;
    margin: 0 !important;
    margin-left: 2% !important;
  }
  #main .list .item:nth-child(3n+1) {
    margin-left: 0 !important;
  }
  #main .list .item:nth-child(n+4) {
    margin-top: 2% !important;
  }
}