* {
  list-style: none;
  text-decoration: none;
  margin: 0;
  padding: 0;
  /* --content_width: 60%;
  --spContent_width: 375px; */
}

header {
  position: sticky;
  top: 0;
  background-color: #fff;
}

h1 {
  display: block;
  width: 60%;
  margin: 0 auto;
}

h1 a {
  color: #0c0c0c;
  font-family: "MS Mincho";
  margin: 16px auto;
  display: inline-block;
  position: relative;
}

h1 a::before {
  content: "";
  display: inline-block;
  width: 190px;
  height: 40px;
  border: solid 1px #000;
  position: absolute;
  top: -10px;
  left: -25px;
}

h1 a::after {
  content: "";
  display: inline-block;
  width: 190px;
  height: 40px;
  border: solid 1px #000;
  position: absolute;
  top: 3px;
  left: 33px;
}

.header_nav {
  background-color: #2a2a2a;
  width: 100%;
  height: 40px;
}

.header_nav ul {
  display: flex;
  width: 60%;
  margin: auto auto;
}

.header_nav a {
  color: #fff;
  line-height: 40px;
  font-size: 0.85em;
}

.header_nav a:hover {
  border-bottom: solid 1px #fff;
}

.header_nav li:nth-child(1) {
  margin-right: 48px;
}

.header_nav li:nth-child(2) {
  margin-right: 48px;
}

.header_nav li:nth-child(3) {
  margin-right: 48px;
}

.header_nav li:nth-child(4) {
  margin-right: 48px;
}

@media (max-width: 500px) {
  header {
    position: fixed;
    top: 0;
    background-color: #fff;
    width: 100%;
  }

  h1 {
    display: block;
    width: 60%;
    margin: 16px auto 16px 16px;
  }

  h1 a {
    color: #0c0c0c;
    font-family: "MS Mincho";
    margin: 8px auto;
    display: inline-block;
    position: relative;
  }

  h1 a::before {
    content: "";
    display: inline-block;
    width: 165px;
    height: 40px;
    border: solid 1px #000;
    position: absolute;
    top: -10px;
    left: 1px;
  }

  h1 a::after {
    content: "";
    display: inline-block;
    width: 165px;
    height: 40px;
    border: solid 1px #000;
    position: absolute;
    top: 3px;
    left: 33px;
  }

  .header_nav {
    background-color: #2a2a2a;
    width: 100%;
    height: 40px;
  }

  .header_nav ul {
    display: flex;
    width: 350px;
    margin: 0 auto;
  }

  .header_nav a {
    color: #fff;
    line-height: 40px;
    font-size: 0.85em;
  }

  .header_nav a:hover {
    border-bottom: solid 1px #fff;
  }

  .header_nav li:nth-child(1) {
    margin: 0 12px;
  }

  .header_nav li:nth-child(2) {
    margin: 0 12px;
  }

  .header_nav li:nth-child(3) {
    margin: 0 12px;
  }

  .header_nav li:nth-child(4) {
    margin: 0 12px;
  }
}