@charset "utf-8";

*,
::before,
::after {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

ul,
ol {
  list-style: none;
}

a {
  color: inherit;
  text-decoration: none;
}

body {
  font-family:
    -apple-system,
    BlinkMacSystemFont,
    "PingFang SC",
    "Hiragino Sans GB",
    "Microsoft YaHei",
    "Noto Sans SC",
    "Source Han Sans SC",
    "Segoe UI",
    Roboto,
    "Helvetica Neue",
    Arial,
    sans-serif;
  font-weight: 400;
  font-size: 16px;
  color: #111;
  line-height: 1.65;
  background-color: #ffffff;
  -webkit-text-size-adjust: 100%;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

.header-inner {
  max-width: 1200px;
  height: 100px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 0;
  padding-right: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.toggle-menu-button {
  display: none;
}

.header-logo {
  display: block;
  width: 200px;
}

.site-menu ul {
  display: flex;
}

.site-menu ul li {
  margin-left: 20px;
  margin-right: 20px;
}

.site-menu ul li a {
  font-family: 'Montserrat', sans-serif;
  font-weight: bold;
}

.gnav {
  display: flex;
  height: 2rem;
  margin: 0 auto;
  width: 400px;
}

.gnav > li {
  width: 25%;
}

.gnav li {
  list-style: none;
  position: relative;
}

.gnav li a {
  background: #0f2e86;
  border-right: 1px solid #eee;
  color: #fff;
  display: block;
  height: 2rem;
  line-height: 2rem;
  text-align: center;
  text-decoration: none;
  width: 100%;
}

.gnav li li {
  height: 0;
  overflow: hidden;
  transition: 0.3s;
}

.gnav li li a {
  border-top: 1px solid #eee;
}

.gnav li:hover > ul > li,
.gnav li:focus-within > ul > li {
  height: 2rem;
  overflow: visible;
}

.recommended {
  background-color: #ffffff;
  padding-top: 45px;
  padding-bottom: 55px;
}

.recommended h2 {
  font-size: 35px;
  font-weight: bold;
  text-align: center;
}

.recommended h2::after {
  content: "";
  display: block;
  width: 36px;
  height: 3px;
  background-color: #000000;
  margin-top: 20px;
  margin-left: auto;
  margin-right: auto;
}

.item-list {
  display: flex;
  padding-top: 40px;
  padding-bottom: 10px;
  padding-left: 60px;
  padding-right: 60px;
  overflow-x: auto;
  overflow-y: hidden;
  margin-left: auto;
  -webkit-overflow-scrolling: touch;
}

.item-list li {
  flex-shrink: 0;
  width: 500px;
  margin-left: 75px;
}

.item-list li:first-child {
  margin-left: 0;
}

.item-list dl {
  margin-top: 20px;
}

.item-list dt {
  font-weight: bold;
}

.footer {
  color: #000000;
  background-color: #0f2e86;
  padding-top: 30px;
  padding-bottom: 15px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.footer-logo {
  display: block;
  width: 400px;
  margin-top: 90px;
}

.footer-tel {
  font-size: 26px;
  font-weight: bold;
  margin-top: 28px;
}

.footer-email {
  font-size: 20px;
  margin-top: 16px;
}

.copyright {
  font-size: 14px;
  font-weight: bold;
  margin-top: 90px;
}

@media (max-width: 800px) {
  body {
    font-family:
      -apple-system,
      BlinkMacSystemFont,
      "PingFang SC",
      "Hiragino Sans GB",
      "Microsoft YaHei",
      "Noto Sans SC",
      "Source Han Sans SC",
      sans-serif;
    font-size: 16px;
    font-weight: 400;
    line-height: 1.7;
    color: #111;
    background-color: #ffffff;
    -webkit-text-size-adjust: 100%;
  }

  .site-menu ul {
    display: block;
    text-align: center;
    margin-right: 0;
  }

  .site-menu li {
    margin-top: 20px;
  }

  .gnav {
    display: flex;
    height: 2rem;
    margin: auto;
    width: 200px;
  }

  .gnav > li {
    width: 50%;
  }

  .gnav li {
    list-style: none;
    position: relative;
  }

  .gnav li a {
    background: #0f2e86;
    border-right: 1px solid #eee;
    color: #fff;
    display: block;
    height: 2rem;
    line-height: 2rem;
    text-align: center;
    text-decoration: none;
    width: 100%;
  }

  .gnav li li {
    height: 0;
    overflow: hidden;
    transition: 0.2s;
  }

  .gnav li li a {
    border-top: 1px solid #eee;
  }

  .gnav li:hover > ul > li,
  .gnav li:focus-within > ul > li {
    height: 2rem;
    overflow: visible;
  }

  .header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: #ffffff;
    height: 50px;
    z-index: 10;
    box-shadow: 0 3px 6px rgba(0, 0, 0, 0.1);
  }

  .header-inner {
    padding-left: 30px;
    padding-right: 30px;
    height: 100%;
    position: relative;
  }

  .header-logo {
    width: 100px;
  }

  .header-site-menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    color: #ffffff;
    background-color: #736E62;
    padding-top: 30px;
    padding-bottom: 50px;
    display: none;
  }

  .header-site-menu.is-show {
    display: block;
  }

  .toggle-menu-button {
    display: block;
    width: 44px;
    height: 34px;
    background-image: url(../images/common/icon-menu.png);
    background-size: 50%;
    background-position: center;
    background-repeat: no-repeat;
    background-color: transparent;
    border: none;
    border-radius: 0;
    outline: none;
  }

  .main {
    padding-top: 50px;
  }

  .recommended {
    background-color: #ffffff;
    padding-top: 45px;
    padding-bottom: 55px;
  }

  .recommended h2 {
    font-size: 35px;
    font-weight: bold;
    text-align: center;
  }

  .recommended h2::after {
    content: "";
    display: block;
    width: 36px;
    height: 3px;
    background-color: #000000;
    margin-top: 20px;
    margin-left: auto;
    margin-right: auto;
  }

  .item-list {
    display: flex;
    padding-top: 40px;
    padding-bottom: 10px;
    padding-left: 20px;
    padding-right: 20px;
    overflow-x: auto;
    overflow-y: hidden;
    margin-left: auto;
    -webkit-overflow-scrolling: touch;
  }

  .item-list li {
    flex-shrink: 0;
    width: 220px;
    margin-left: 20px;
  }

  .item-list li:first-child {
    margin-left: 0;
  }

  .item-list dl {
    margin-top: 20px;
  }

  .item-list dt {
    font-weight: bold;
  }

  .footer-logo {
    width: 260px;
    margin-top: 60px;
  }

  .footer-tel {
    font-size: 20px;
  }

  .footer-email {
    font-size: 16px;
  }

  .copyright {
    margin-top: 50px;
    font-size: 12px;
    text-align: center;
    padding-left: 15px;
    padding-right: 15px;
  }
}

修正の要点は次のとおりです。