#main_visual {
  width: 100%;
  overflow: hidden;
}
#main_visual a {
  width: 25%;
  display: block;
  float: left;
}
#main_visual a img {
  display: block;
  width: 100%;
  height: auto;
}

.fb {
  max-width: 980px;
  margin: 30px auto;
}
.fb .fb-like-box {
  width: 100% !important;
}
.fb .fb-like-box span {
  width: 100% !important;
  display: block;
}
.fb .fb-like-box iframe {
  width: 100% !important;
}

@media screen and (max-width: 640px) {
  #main_visual a {
    width: 50%;
  }

  .fb {
    width: 100%;
  }
}