@media screen and (max-width:1161px){
    .principles {

        display: flex;
        justify-content: center;
        flex-direction: column;
        align-items: center;
    }
    .right {
        width: 520px;
        background: #F5F5F5;
        border: 1px solid #D7D7D7;
        box-sizing: border-box;
        border-radius: 3px;
        margin-left: 0px;
        margin-top: 10px;
    }
    .row {
        display: flex;
        justify-content: center;
        flex-direction: column;
        align-items: center;
    }
    .first {
        width: 336px;
        display: flex;
        align-items: center;
        flex-direction: column;
        background: #F5F5F5;
        margin-right: 0px;
        text-align: center;
        margin-top: 10px;
    
    }
    .third {
        width: 336px;
        display: flex;
        align-items: center;
        flex-direction: column;
        background: #F5F5F5;
        margin-right: 0px;
        text-align: center;
        margin-top: 10px;
    
    }
    .second {
        width: 336px;
        display: flex;
        align-items: center;
        flex-direction: column;
        background: #F5F5F5;
        margin-right: 0px;
        text-align: center;
        margin-top: 10px;
    }
    .gear {
        background-image: url(../img/mech2.png);
        background-color: 
        rgba(0,0,0,.8);
        width: 650px;
        border-radius: 3px;
        margin-top: 47px;
    }
    .con {
        display: flex;
        justify-content: center;
        align-items: center;
        flex-direction: column;
    }
    .right1 {

        background: 
    
    #F5F5F5;
    
    border: 1px solid
    
        #D7D7D7;
        box-sizing: border-box;
        border-radius: 3px;
        width: 382px;
        margin-left: 0px;
        display: flex;
        margin-top: 10px;
    }
    .left2 {

        background: 
    
    #F5F5F5;
    
    border: 1px solid
    
        #D7D7D7;
        box-sizing: border-box;
        border-radius: 3px;
        width: 650px;
        display: flex;
    }
    .conn {
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
    }
    h7{
        text-align: center;
    }
    .bg {
        background-color: 
        white;
        width: 650px;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
    }
    .row1 {
        display: flex;
        justify-content: center;
        padding-bottom: 70px;
        flex-direction: column;
        align-items: center;
    }
    .first1 {

        width: 336px;
        display: flex;
        align-items: center;
        flex-direction: column;
        background: 
    
        #F5F5F5;
        margin-right: 0px;
        text-align: center;
    }
    .second1 {
        margin-top: 10px;
        width: 336px;
        display: flex;
        align-items: center;
        flex-direction: column;
        background: 
        #F5F5F5;
        margin-right: 0px;
        text-align: center;
    }
    .third1 {
        width: 336px;
        display: flex;
        align-items: center;
        flex-direction: column;
        background: 
        #F5F5F5;
        text-align: center;
        margin-top: 10px;
    }
}
@media screen and (max-width:690px){
    .gear {
    width: 450px;
    }
    .left2 {
    width: 450px
    }
    .leftt {

        background: url(../img/door.png);
            background-color: rgba(0, 0, 0, 0);
        background-color: 
    
        rgba(0,0,0,.8);
        width: 450px;
        padding-left: 30px;
    
    }
    .bg {

        background-color: 
    
        white;
        width: 450px;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
    
    }
    .rightt {

        width: 450px;
        padding-left: 30px;
    }
}
@media screen and (max-width:582px){
    .left {
        width: 350px;
        border: 1px solid 
    #D7D7D7;
    box-sizing: border-box;
    border-radius: 3px;
    background:
        #484848;
    }
    .right {
        width: 350px;
    }
    .gear {
        width: 350px;
    }
    .left1 {
        width: 350px;
    }
    .right1 {
        width: 350px;
    }
    .left2 {

        width: 350px;
    }
    .leftt {
        width: 350px;
    }
    .bg {

        background-color: 
    
        white;
        width: 350px;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
    
    }
    .rightt {

        width: 350px;
        padding-left: 30px;
    }
}
@media screen and (max-width:390px){
    .left {
        width: 290px;
        border: 1px solid 
    #D7D7D7;
    box-sizing: border-box;
    border-radius: 3px;
    background:
        #484848;
    }
    .right {
        width: 290px;
    }
    .gear {
        width: 290px;
    }
    .left1 {
        width: 290px;
    }
    .right1 {
        width: 290px;
    }
    .left2 {

        width: 290px;
    }
    .leftt {
        width: 290px;
    }
    .bg {

        background-color: 
    
        white;
        width: 290px;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
    
    }
    .rightt {

        width: 290px;
        padding-left: 30px;
    }
    .second1{
        width: 290px;
    }
    .first1{
        width: 290px;
    }
    .third1{
        width: 290px;
    }
}