h2 {
  font-size: 30px;
  font-weight: bold;
  text-align: center;
  position: relative;
  padding: 5px 0;
  margin-top: 60px;
  margin-bottom: 60px;
}
h2:after {
  content: "";
  width: 150px;
  height: 2px;
  display: block;
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  margin: 0 auto;
  background-color: #555555;
}

h3 {
  display: flex;
  font-size: 26px;
  font-weight: bold;
  margin-bottom: 1em;
  padding-top: 2em;
  text-align: left;
  border-bottom: 2px solid #555555;
}
h3:first-of-type {
  margin-top: 0;
}
@media screen and (max-width: 999px) {
  h3 {
    font-size: 2.60417vw;
  }
}
@media screen and (max-width: 768px) {
  h3 {
    font-size: 4.6875vw;
  }
}


#topics .inner .flex {
  display: -webkit-flex;
  display: -moz-flex;
  display: -ms-flex;
  display: -o-flex;
  display: flex;
  -webkit-flex-direction: row;
  flex-direction: row;
  -webkit-flex-wrap: wrap;
  flex-wrap: wrap;
  -webkit-justify-content: left;
  justify-content: left;
  -webkit-align-items: stretch;
  align-items: stretch;
  -webkit-align-content: flex-start;
  align-content: flex-start;
}
#topics .inner .flex .tpc_box {
  width: 23%;
  margin: 1%;
  display: block;
  text-decoration: none;
}
#topics .inner .flex .tpc_box:hover .cnt_box .title {
  text-decoration: underline;
}
@media screen and (max-width: 768px) {
  #topics .inner .flex .tpc_box {
    width: 48%;
  }
}
#topics .inner .flex .tpc_box .thmb {
  display: block;
  background-repeat: no-repeat;
  background-size: cover;
  background-position: center;
  height: 180px;
}
#topics .inner .flex .tpc_box .cnt_box {
  color: #333;
  padding: 20px 0;
}
#topics .inner .flex .tpc_box .cnt_box .date {
  font-size: 14px;
  display: block;
  text-align: left;
  margin-bottom: 10px;
}
#topics .inner .flex .tpc_box .cnt_box .title {
  display: block;
  text-align: left;
}

/* もっと見る機能：最初は4つまで表示 */
#topics .inner .flex .tpc_box:nth-child(n+5) {
  display: none;
}

/* show-allクラスが付いたら全て表示 */
#topics .inner .flex.show-all .tpc_box {
  display: block;
}
@media screen and (max-width: 768px) {
  #topics .inner .flex.show-all .tpc_box {
    display: block;
  }
}