nav {
  display: block;
  width: 180px;
  position: fixed;
  top: 0;
  right: -300px;
  bottom: 0;
  transition: all 0.5s;
  z-index: 300;
}

.open nav {
  right: 0;
  opacity: 1;
}

nav .inner {
  padding-left: 0px;
  background-color: rgba(255, 255, 255, 0.6);
  height: 100%;
}

nav .inner ul {
  list-style: none;
  margin: 0;
  padding-top: 150px;
}

nav .inner ul li {
  margin: 0;
  text-align: end;
}

nav .inner ul li a {
  display: block;
  text-decoration: none;
  color: #333;
  font-family: "dnp-shuei-mgothic-std", sans-serif;
  font-weight: 400;
  font-style: normal;
  font-size: 16px;
  padding: 1.5rem;
  transition-duration: 0.2s;
}

nav .inner ul li a:hover {
  text-decoration: underline;
  text-underline-offset: 0.5em;
  text-decoration-thickness: 3px;
}


/* ボタンのための記述 */

.toggle-btn {
  position: fixed;
  top: 50px;
  right: 0px;
  z-index: 9998;
  cursor: pointer;
  width: 80px;
  height: 60px;
}

.toggle-btn span {
  display: inline-block;
  transition: all .4s;
  position: absolute;
  left: 10px;
  height: 2px;
  border-radius: 2px;
  background-color: #333;
  width: 75%;
}

.toggle-btn span:nth-child(1) {
  top: 15px;
}

.toggle-btn span:nth-child(2) {
  top: 26px;
}

.toggle-btn span:nth-child(3) {
  top: 37px;
}

.open .toggle-btn span {
  background-color: #333;
}

.open .toggle-btn span:nth-child(1) {
  top: 30px;
  left: 10px;
  transform: translateY(-0px) rotate(-315deg);
  width: 75%;
}

.open .toggle-btn span:nth-child(2) {
  opacity: 0;
}

.open .toggle-btn span:nth-child(3) {
  top: 30px;
  left: 10px;
  transform: translateY(0px) rotate(315deg);
  width: 75%;
}