* {
    list-style: none;
    /* text-decoration: none; */
    color: #707070;
    font-family: "Yu Gothic Medium", "游ゴシック Medium", YuGothic, "游ゴシック体",
      "ヒラギノ角ゴ Pro W3", "メイリオ", sans-serif;
  }
  
  body {
    margin: 0 auto;
    font-size: 16px;
    color: #555;
  }

      /* header & footer */ 
  header {
    border-bottom: solid 1px #ddd;
    padding-bottom: 10px;
    margin-top: 2rem;
  }

  .header-sp {
    display: none;
  }

  .nav-container {
    max-width: 985px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
  }

  .nav-container > .logo {
    justify-content: start;
    align-items: center;
    width: 124px;
  }

  .nav-container > .logo > a > img {
    width: 124px;
  }

  .nav-container > .menu-left {
    display: flex;
    gap: 2rem;
    align-items: center;
  }

  .menu-left > li > a {
    position: relative;
  }

  .menu-left > li > a::after {
    position: absolute;
    left: 0;
    content: "";
    width: 100%;
    height: 1px;
    background: #555;
    bottom: -1px;
    visibility: hidden;
  }

  .menu-left > li > a:hover::after {
    visibility: visible;
  }

  .nav-container > .menu-right {
    display: flex;
    justify-content: end;
    gap: 10px;
  }

      /* footer */
      footer {
        padding: 10px 0;
        font-size: 80%;
        text-align: center;
        width: 985px;
        margin: 0 auto;
      }
    
      .footer-sp {
        display: none;
      }
    
      .footer-nav-container {
        display: flex;
        justify-content: space-between;
      }
      .footer-top-border {
        border-top: solid 1px #ddd;
        padding: 10px 0;
        font-size: 80%;
        text-align: center;
        width: 100%;
        margin-top: 5rem;
      }
    
      .footer-nav-container > .footer-logo {
        justify-content: start;
        align-items: center;
      }
    
      .footer-nav-container > .footer-logo > a > img {
        width: 124px;
      }
    
      .footer-menu-left {
        display: flex;
        gap: 2rem;
        align-items: center;
      }
    
      .sns {
        display: flex;
        align-items: center;
        gap: 10px;
      }
    
      .footer-bottom > ul {
        display: flex;
        gap: 10px;
        align-items: center;
        padding: 0;
      }
    
      .copyright {
        border-top: solid 1px #ddd;
        padding: 10px 0;
        font-size: 80%;
        text-align: center;
        width: 100%;
      }

      th,td{
        border:1px #333 solid;
        padding: 1rem 2rem;
        font-weight: 100;
      }

      table{
        border-collapse: collapse;
        text-align: center;
        margin: 5.64rem auto;
      }
    
      .responsive {
        display: none;
      }

  
  @media screen and (min-width: 1279px) {
  
  }
  
  @media screen and (max-width: 1280px) {  

  }
  
  @media only screen and (max-width: 500px) {
        /* header & footer */
    header {
      margin: 0;
    }
  
    .header-sp {
      display: flex;
      justify-content: center;
      align-items: center;
      margin-top: 1rem;
    }
  
    .nav-container {
      display: none;
    }

    .nav-container > .logo > img {
      width: 124px;
    }

    table {
        display:none;
    }

    .responsive {
        display:block;
        margin: 3rem auto;
        width: 72%;
    }

    .responsive ul {
        margin: 0;
        padding: 0;
    }

    .responsive ul li {
        text-align: center;
        padding: 1rem;
    }

    .product-name {
        background-color: #ECECEC;
    }

    .price-change-date{
        border-top: 1px #ECECEC solid;
    }

  
  
    /* footer */
    footer {
      display: none;
    }
  
    .footer-sp {
      display: flex;
      justify-content: center;
      align-items: center;
    }
  
    .copyright {
      border-top: solid 1px #ddd;
      padding: 10px 0;
      font-size: 80%;
      text-align: center;
      width: 100%;
    }
  }