@media only screen and (min-width: 768px) and (max-width: 991px) {
    .header {
        -ms-flex-wrap: wrap;
        flex-wrap: wrap;
    }

    .header-left {
        -webkit-box-ordinal-group: 1;
        -ms-flex-order: 0;
        order: 0;
    }

    .header-middle {
        -webkit-box-ordinal-group: 3;
        -ms-flex-order: 2;
        order: 2;
        -webkit-box-flex: 1;
        -ms-flex: 1;
        flex: 1;
    }

    .header-right {
        -webkit-box-ordinal-group: 2;
        -ms-flex-order: 1;
        order: 1;
    }

    .header-middle ul {
        -ms-flex-pack: distribute;
        justify-content: space-around;
    }

    .right-box {
        top: 73px;
        height: calc(100vh - 100px);
    }

    .header-area {
        position: fixed;
        left: 0;
        width: 100%;
    }

    .right-sidebar {
        top: 73px;
        position: fixed;
        background: #fff;
        margin-top: 20px;
        box-shadow: 0 0 5px rgb(0 0 0 / 66%);
        width: 470px;
        z-index: 10;
    }

    .right-sidebar {
        right: -470px;
    }

    .example-box-list {
        height: calc(100vh - 650px);
    }

    .widget-list {
        height: calc(100vh - 450px);
    }

    .main-content-area {
        padding-top: 90px;
    }
}

@media only screen and (max-width: 767px) {
    .header {
        -ms-flex-wrap: wrap;
        flex-wrap: wrap;
    }

    .header-left {
        -webkit-box-ordinal-group: 1;
        -ms-flex-order: 0;
        order: 0;
        flex: 1;
    }

    .header-middle {
        -webkit-box-ordinal-group: 3;
        -ms-flex-order: 1;
        order: 1;
        -webkit-box-flex: 1;
        -ms-flex: 1;
        flex: 1;
        border-top: #173452 solid 1px;
    }

    .header-right {
        -webkit-box-ordinal-group: 2;
        -ms-flex-order: 2;
        order: 2;
    }

    .header-middle ul {
        -ms-flex-pack: distribute;
        justify-content: space-around;
    }

    .right-box {
        top: 37px;
        height: calc(100vh - 72px);
        width: 300px;
        left: -300px;
    }

    .header-area {
        position: fixed;
        left: 0;
        width: 100%;
    }

    .right-sidebar {
        top: 37px;
        position: fixed;
        background: #fff;
        margin-top: 0px;
        box-shadow: 0 0 5px rgb(0 0 0 / 66%);
        width: 300px;
        z-index: 10;
    }

    .right-sidebar {
        right: -300px;
    }

    .example-box-list {
        height: calc(100vh - 365px);
    }

    .widget-list {
        height: calc(100vh - 185px);
    }

    .main-content-area {
        padding-top: 45px;
    }

    .header ul li a span,
    .header ul li button span,
    .header-right a span {
        display: none;
    }

    .right-siderbar-header li.nav-item {
        -webkit-box-flex: 0;
        -ms-flex: 0 0 50%;
        flex: 0 0 50%;
        margin-top: 2px;
    }

    .header ul li {
        padding: 6px 8px 9px;
    }

    .instructor {
        margin-top: 20px;
    }
}