@media (max-width: 900px) {
/* header */
  .pc_nav,
  .logo {
    display: none;
  }

  .logo {
    position: fixed;
    top: 3px;
    left: 50%;
    margin-left: -37px;
    display: block;
    width: 70px;
    height: 70px;
    border-radius: 50%;
    background-color: #fff;
    border: 2px solid #3292C0;
  }

  .nav_btn {
    display: block;
    width: 40px;
    position: fixed;
    top: 25px;
    right: 20px;
  }

  .nav_btn li {
    width: 100%;
    border-bottom: 3px solid #3292C0;
    list-style: none;
    margin-bottom: 10px;
  }

  .rotate1 {
    transform: translate(0, 12.8px) rotate(45deg);
    transition: transform .2s ease-out;
  }

  .rotate2 {
    transform: translate(0, -12.8px) rotate(-45deg);
    transition: transform .2s ease-out;
  }

  .rotate3 {
    transform: translate(0, 0) rotate(0);
    transition: transform .2s ease-out;
  }

  .rotate4 {
    transform: translate(0, 0) rotate(0);
    transition: transform .2s ease-out;
  }

  .nav_small {
    width: 100%;
    position: fixed;
    top: 80px;
    padding: 40px 0;
    background-color: rgba(255,255,255,.9);
    text-align: center;
    overflow-y: scroll;
  }

  .nav_small li {
    list-style: none;
    padding: 10px;
    margin: 5px;
    color: #3292C0;
    font-weight: normal;
    border-bottom: 1px dotted #3292C0;
  }

  .nav_small::-webkit-scrollbar {
    width: 0;
  }
/* header_ends */
}



@media (max-width: 750px) {
/* footer */
  .link_wrapper li {
    font-size: 12px;
  }

  .up_btn {
    width: 50px;
    height: 50px;
  }

  .up_btn span {
    display: none;
  }
/* footer_ends */
}



@media (min-width: 900px) {
  .nav_small li {
    display: none;
  }
}