.product {
  padding: 40px 0 0;
}
.content_min.study {
  padding: 0;
}
.content_min.gallery {
  padding: 0 0 60px;
}
.h3_title {
  max-width: 870px;
  margin: 40px auto 0;
  border-left: 1px solid grey;
  border-bottom: 1px solid grey;
  padding: 0 0 10px 20px;
  font-size: 1.8rem;
  font-weight: bold;
}
.box {
  display: flex;
  flex-wrap: wrap;
  max-width: 870px;
  margin: 0 auto;
}
.box .image {
  width: 32%;
}
.margin-r {
  margin-right: 2%;
}
.margin-b {
  margin-bottom: 2%;
}

@media screen and (max-width: 768px) {
  .box {
    display: block;
  }
  .box .image {
    width: 100%;
  }
}