@media (min-width: 768px) {
  .p60 {
    padding-top: 60px;
    padding-bottom: 60px;
  }

  .p50 {
    padding-top: 50px;
    padding-bottom: 50px;
  }

  .p40 {
    padding-top: 40px;
    padding-bottom: 40px;
  }

  .p30 {
    padding-top: 30px;
    padding-bottom: 30px;
  }

  .p20 {
    padding-top: 20px;
    padding-bottom: 20px;
  }

  .mb50 {
    margin-bottom: 50px;
  }

  .mb40 {
    margin-bottom: 40px;
  }

  .mb20 {
    margin-bottom: 20px;
  }

  .mb30 {
    margin-bottom: 30px;
  }

  .mb10 {
    margin-bottom: 10px;
  }

  .mt10 {
    margin-top: 10px;
  }

  .mt20 {
    margin-top: 20px;
  }

  .mt30 {
    margin-top: 30px;
  }

  .mt40 {
    margin-top: 40px;
  }

  .mt50 {
    margin-top: 50px;
  }
}

@media (max-width: 768px) {
  .content article {
    padding: 20px;
  }

  .book-info h3 {
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
  }

  .book-title-cell {
    max-width: 220px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .book-info h3 a {
    vertical-align: top;
  }

  .book-info .author {
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
  }

  .header-menu {
    padding-left: 0;
    position: absolute;
    height: auto;
    left: 0;
    right: 0;
    top: 100%;
    bottom: auto;
    background: #fff;
    -webkit-transform: scaleY(0);
    transform: scaleY(0);
    transition: 0.3s opacity, 0.3s 0.3s visibility, 0.3s -webkit-transform;
    transition: 0.3s transform, 0.3s opacity, 0.3s 0.3s visibility;
    transition: 0.3s transform, 0.3s opacity, 0.3s 0.3s visibility,
      0.3s -webkit-transform;
    -webkit-transform-origin: top center;
    transform-origin: top center;
    visibility: hidden;
    opacity: 0;
    z-index: 10;
  }

  .header-menu.active {
    -webkit-transform: scaleY(1);
    transform: scaleY(1);
    opacity: 1;
    visibility: visible;
    transition: 0.3s 0.1s transform, 0.3s 0.1s opacity, 0.1s visibility;
  }

  .header-menu ul li {
    float: none;
    position: relative;
    text-align: center;
    margin-bottom: 10px;
    height: 30px;
    line-height: 30px;
    width: 100%;
    border-bottom: none;
    margin-right: 0;
  }

  .header-menu > ul > li > a {
    display: block;
    font-size: 16px;
    position: relative;
    padding: 0 20px;
    color: #000;
    height: 30px;
    line-height: 30px;
  }

  .p60 {
    padding-top: 30px;
    padding-bottom: 30px;
  }

  .p50 {
    padding-top: 25px;
    padding-bottom: 25px;
  }

  .p40 {
    padding-top: 20px;
    padding-bottom: 20px;
  }

  .p30 {
    padding-top: 15px;
    padding-bottom: 15px;
  }

  .p20 {
    padding-top: 10px;
    padding-bottom: 10px;
  }

  .mb50 {
    margin-bottom: 25px;
  }

  .mb40 {
    margin-bottom: 20px;
  }

  /* .mb20 {
        margin-bottom: 10px
    } */

  .mb30 {
    margin-bottom: 15px;
  }

  .mb10 {
    margin-bottom: 10px;
  }

  .mt10 {
    margin-top: 10px;
  }

  .mt20 {
    margin-top: 10px;
  }

  .mt30 {
    margin-top: 15px;
  }

  .mt40 {
    margin-top: 20px;
  }

  .mt50 {
    margin-top: 25px;
  }

  /* 移动端适配 */
  @media (max-width: 767px) {
    .search-box.pull-right {
      width: 100%;
        position:relative;
        top: 5px;
    }
  }

  @keyframes spin {
    from {
      transform: rotate(0deg);
    }

    to {
      transform: rotate(360deg);
    }
  }

  /* 移动端适配 */
  @media (max-width: 767px) {
    .collect-btn {
      right: 5px;
      font-size: 20px;
    }
  }

@media (max-width:767px){
    .book-catalog ul li {
        width: 100%;
    }
}

  @media (min-width: 768px) {
    .back-to-top {
      right: calc((100% - 1170px) / 2 + 20px);
    }
  }

  @media (max-width: 767px) {
    .reading-controls .btn-group {
      margin-right: 10px;
    }

    .btn-group .btn {
      padding: 5px 10px;
    }
  }

  @media (hover: hover) {
    a:hover {
      color: #ff8f00;
      text-decoration: none;
    }
  }
}