main#about {
  display: flex;
  flex-wrap: wrap;
}
main#about #hero {
  width: 100%;
  height: 800px;
  position: relative;
}
main#about #hero::after {
  content: "";
  width: 30%;
  max-width: 150px;
  height: 260px;
  position: absolute;
  right: 0;
  bottom: -280px;
  background: url("../images/about_leaves_R.png") no-repeat bottom left/cover;
}
main#about #hero img {
  object-fit: cover;
  width: 100%;
  height: 100%;
}
main#about #management {
  width: 50%;
  padding: 2em 1em;
  text-align: center;
  position: relative;
  z-index: 100;
}
main#about #management h1 {
  font-size: 4.2rem;
  margin-bottom: 1.25em;
}
main#about #management p {
  font-size: 1.85rem;
  line-height: 1.9;
}
main#about #history {
  width: 50%;
  padding: 2em 1em;
  border-left: 1px solid var(--c-color);
  position: relative;
}
main#about #history::after {
  content: "";
  width: 30%;
  max-width: 150px;
  height: 200px;
  position: absolute;
  left: -100%;
  bottom: -30px;
  background: url("../images/about_leaves_L.png") no-repeat bottom left/cover;
}
main#about #history h1 {
  color: var(--c-color);
  font-size: 4.2rem;
  margin-bottom: 1.25em;
  text-align: center;
}
main#about #history div.history_list {
  display: flex;
  flex-direction: column;
  width: 70%;
  margin: 0 auto;
  position: relative;
  z-index: 100;
}
main#about #history div.history_list::before {
  content: "";
  width: 1px;
  height: 0;
  position: absolute;
  top: -5%;
  left: -40px;
  background: var(--c-color);
}
main#about #history div.history_list.active::before {
  animation: extend_animation 1.8s ease-in 0s 1 normal forwards;
}
main#about #history div.history_list dl {
  font-size: 1.8rem;
  margin-bottom: 4.5em;
  opacity: 0;
}
main#about #history div.history_list dl dt {
  margin-bottom: 0.7em;
  position: relative;
}
main#about #history div.history_list dl dt::before {
  content: "";
  width: 20px;
  height: 20px;
  border-radius: 50px;
  position: absolute;
  top: 7px;
  left: -50px;
  background: var(--c-color);
}
main#about #history div.history_list.active dl:nth-child(1) {
  animation: circle_animation 0.3s ease-in 0.45s 1 normal forwards;
}
main#about #history div.history_list.active dl:nth-child(2) {
  animation: circle_animation 0.3s ease-in 0.9s 1 normal forwards;
}
main#about #history div.history_list.active dl:nth-child(3) {
  animation: circle_animation 0.3s ease-in 1.35s 1 normal forwards;
}
main#about #history div.history_list.active dl:nth-child(4) {
  animation: circle_animation 0.3s ease-in 1.8s 1 normal forwards;
}

@keyframes extend_animation {
  0% {
    height: 0;
  }
  100% {
    height: 95%;
  }
}
@keyframes circle_animation {
  0% {
    opacity: 0;
  }
  100% {
    opacity: 1;
  }
}
@media screen and (max-width: 768px) {
  main#about {
    justify-content: center;
  }
  main#about #hero {
    height: 600px;
  }
  main#about #management {
    width: 100%;
  }
  main#about #management h1 {
    font-size: 2.4rem;
  }
  main#about #management p {
    font-size: 1.6rem;
  }
  main#about #history {
    width: 90%;
    padding: 2em 0;
    border-left: none;
    border-top: 1px solid var(--c-color);
  }
  main#about #history::after {
    left: 0;
  }
  main#about #history h1 {
    font-size: 2.4rem;
  }
  main#about #history div.history_list {
    width: 80%;
    margin: 0 0 0 auto;
  }
  main#about #history div.history_list dl {
    font-size: 1.6rem;
    margin-bottom: 2.5em;
  }
}