body {
  font-family: "Noto Sans JP", sans-serif;
  font-weight: 500;
  color: #7c7b76;
  font-size: 1.3vw;
  width: 100%;
  text-align: center;
}

img {
  width: 60%;
}
@media screen and ( max-width: 767px ) {
  img {
    width: 100%;
  }
}

.btn-hover {
  display: none;
}

.btn {
  position: absolute;
  bottom: 30%;
  width: 100%;
  text-align: center;
}
.btn img {
  width: 40%;
}
@media screen and ( max-width: 767px ) {
  .btn img {
    width: 70%;
  }
}

footer {
  position: relative;
  margin-bottom: 20px;
}
footer .btn {
  bottom: 0;
}
footer .btn img {
  width: 55%;
}
@media screen and ( max-width: 767px ) {
  footer .btn img {
    width: 95%;
  }
}