@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;
    }
}