header {
  position: fixed;
  height: 100px;
  width: 100%;
  z-index: 99;
}

.header_btn {
  background-color: #000;
  height: 100px;
  width: 100px;
  margin: 0 0 0 auto;
  position: relative;
  cursor: pointer;
  z-index: 99;
}
.header_btn span {
  height: 2px;
  width: 40px;
  background-color: #fff;
  position: absolute;
  left: 30%;
  -webkit-transition: all 0.4s;
  transition: all 0.4s;
}
.header_btn span:nth-child(1) {
  top: 40%;
}
.header_btn span:nth-child(2) {
  top: 50%;
}
.header_btn span:nth-child(3) {
  top: 60%;
}
.header_btn.active span {
  left: 30%;
}
.header_btn.active span:nth-child(1) {
  top: 45%;
  -webkit-transform: translateY(6px) rotate(-30deg);
          transform: translateY(6px) rotate(-30deg);
}
.header_btn.active span:nth-child(2) {
  opacity: 0;
}
.header_btn.active span:nth-child(3) {
  top: 45%;
  -webkit-transform: translateY(6px) rotate(30deg);
          transform: translateY(6px) rotate(30deg);
}

#nav {
  background: #000;
  position: relative;
  top: -100px;
  right: -500px;
  width: 500px;
  height: 100px;
  -webkit-transition: all 0.4s;
  transition: all 0.4s;
  margin: 0 0 0 auto;
  z-index: 50;
}
#nav.panelactive {
  right: 0;
}
#nav ul {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  padding-top: 40px;
}
#nav li {
  -webkit-box-flex: 0;
      -ms-flex: 0 0 35%;
          flex: 0 0 35%;
  position: relative;
  padding-left: 30px;
}
#nav li a {
  color: #fff;
  font-size: 18px;
  letter-spacing: 0.16em;
  font-weight: 700;
}
#nav li:hover {
  opacity: 0.7;
  -webkit-transition: 0.4s;
  transition: 0.4s;
}
#nav li::before {
  content: "";
  background-image: url(../img/nav_point.png);
  background-size: 100%;
  background-repeat: no-repeat;
  position: absolute;
  width: 20px;
  height: 20px;
  left: 0;
  top: 2px;
}

@media (min-width: 1px) and (max-width: 767px) {
  .header_btn {
    height: 60px;
    width: 60px;
  }
  .header_btn span {
    height: 2px;
    width: 30px;
    left: 25%;
  }
  .header_btn span:nth-child(1) {
    top: 35%;
  }
  .header_btn span:nth-child(2) {
    top: 50%;
  }
  .header_btn span:nth-child(3) {
    top: 65%;
  }
  .header_btn.active span {
    left: 25%;
  }
  .header_btn.active span:nth-child(1) {
    top: 45%;
    -webkit-transform: translateY(0) rotate(-30deg);
            transform: translateY(0) rotate(-30deg);
  }
  .header_btn.active span:nth-child(2) {
    opacity: 0;
  }
  .header_btn.active span:nth-child(3) {
    top: 45%;
    -webkit-transform: translateY(0) rotate(30deg);
            transform: translateY(0) rotate(30deg);
  }
  #nav {
    top: 0;
    right: -60px;
    width: 60px;
    height: 100vh;
  }
  #nav ul {
    -webkit-box-pack: justify;
        -ms-flex-pack: justify;
            justify-content: space-between;
    padding-left: 20px;
    -webkit-writing-mode: vertical-rl;
            writing-mode: vertical-rl;
    -ms-writing-mode: tb-rl;
    gap: 10px;
    padding-top: 10px;
  }
  #nav li {
    -webkit-box-flex: 0;
        -ms-flex: 0 0 50%;
            flex: 0 0 50%;
    padding-left: 0;
    padding-top: 25px;
  }
  #nav li a {
    font-size: 12px;
    letter-spacing: 0.16em;
  }
  #nav li::before {
    background-image: url(../img/nav_point_sp.png);
    background-size: 20px;
    width: 30px;
    height: 30px;
    left: -1px;
    top: 0;
  }
}