.back-btn {
  display: block;
  position: absolute;
  padding: 16px 26px 16px 34px;
  top: 6%;
  left: 0%;
  font-size: 18px;
  font-weight: 700;
  color: #fff;
  background: #013274;
  border: none;
  border-radius: 0 80px 80px 0;
  box-shadow: 2px 2px 4px 0 #00315d33;
  cursor: pointer;
  transition: background 0.2s;
  margin-bottom: 16px;
}
.back-btn:hover {
  background: #0c72be;
}
.back-btn__icon {
  position: relative;
}
.back-btn__icon::before {
  content: '';
  position: absolute;
  left: 0%;
  top: 50%;
  transform: translateY(-50%);
  width: 8px;
  height: 12px;
  background: url('../../../assets/common/img/icon-arrowLeft.png') no-repeat center center;
  background-size: contain;
  margin-left: -1.25rem /* 20px (基準16px) */;
}