main h1,
.tab-menu {
  background-color: #060;
}

main h1 span::after {
  content: "YOYOGI JUNIOR HIGH SCHOOL";
}

.mv {
  background: url(../img/mv_sp.jpg) no-repeat center top / 100%;
}

@media (min-width: 768px) {
  .mv {
    background: url(../img/mv_pc.jpg) no-repeat center top / 100%;
  }
}

@media (min-width: 1024px) {
  main h1 {
    width: calc(13em + 4.88%);
  }
}

.tab-menu {
  width: calc((100% - 30px) / 4);
}

.school_name img {
  width: 42px;
}