@media screen and (max-width: 991px) {
  /* hader
  -------------------- */
  #logo {
    width: 160px;
    height: 33px;
  }

  /* nav
  -------------------- */
  #mainNav {
    background-color: #fff;
  }

  #mainNav .navbar-brand {
    padding: 1rem 0;
  }

  .cls-2 {
    fill: #333;
  }

  #mainNav li {
    margin: 0 1.6rem;
  }

  #mainNav.navbar-shrink li {
    margin: 0 1.6rem;
  }

  #mainNav ul ul {
    visibility: visible;
    opacity: 1.0;
    position: static;
  }

  .nav-item.current > a {
    border-bottom: 1px solid #1dc47f;
  }

  #mainNav .lang > a {
    display: inline-block;
    background-color: transparent;
  }

  .navbar-nav {
    background-color: #f8f8f8;
    margin-bottom: 1rem;
    padding-bottom: 1rem;
  }
  .navbar-nav li {
    border-bottom: 2px solid #fff;
  }

  .nav-item a:link, .nav-item a:visited {
    color: black;
  }
  .nav-item a:hover {
    color: #f5c70d;
  }

  .navbar-toggler {
    font-size: 1.6rem;
  }

  /* top
  -------------------- */
  .mds {
    font-size: 2.8rem;
  }

  #bnr-jyomon h2 {
    font-size: 2.1rem;
  }

  .kuma::after {
    width: 25px;
    height: 33px;
    right: -28px;
    padding: 7.5%;
  }

  #jomon-walk .course .btnblock .btn {
    width: 100%;
    min-width: auto;
  }
}
@media screen and (max-width: 767px) {
  /* common
  -------------------- */
  .section {
    padding-top: 10%;
    padding-bottom: 10%;
  }

  .masthead .logotitle {
    width: 200px;
  }
  .masthead .logotitle .logomark img {
    width: auto;
    height: auto;
  }

  .masthead.subhead {
    height: auto;
  }
  .masthead.subhead .logotitle {
    transform: translateY(-30%) translateX(-50%);
    -webkit-transform: translateY(-30%) translateX(-50%);
  }
  .masthead.subhead .logotitle .logomark img {
    width: 200px;
    height: 200px;
  }

  #news .smds {
    text-align: center;
  }

  .newsbox {
    margin-top: 2.0em;
  }
  .newsbox li {
    border-bottom: 1px solid #ccc;
    margin: 0;
    padding-top: 10px;
    padding-bottom: 10px;
  }

  #about h2 {
    font-size: 2.1rem;
  }

  #jomon-walk .course h3 {
    min-height: 0;
  }

  section .h-100 {
    height: auto !important;
  }
}
@media screen and (max-width: 575px) {
  .masthead.subhead {
    height: auto;
  }
  .masthead.subhead .logotitle .logomark img {
    width: 120px;
    height: 120px;
  }

  #jomon-walk .course {
    margin-top: -4%;
    margin-left: 2%;
    margin-right: 2%;
  }

  #jomon-walk .lead br {
    display: none;
  }
}