.main_box{
    background-size: cover;}
@media screen and (min-width: 1401px) and (max-width: 2000px) {
.page-nav{
margin-top: 1%;}

}

@media screen and (min-width: 2001px) and (max-width: 2560px) {
.page-nav{
margin-top: 4%;}

}

@media screen and (min-width: 2561px) and (max-width: 2800px) {
.page-nav{
margin-top: 8%;}

}

@media screen and (min-width: 2801px) and (max-width: 4790px) {
.page-nav{
margin-top: 12%;}

}
@media screen and (min-width: 4791px) and (max-width: 5500px) {
.page-nav{
margin-top: 15%;}

}
/*css*/
.imgbed{
    position: relative;
    display: block;
    height: 0;
    width: 100%;
    padding-top: 0%;}
.imgbed img{
    display: block;
    position: relative;
    top: 0;
    left: 0;
    width: 100%;
    height: auto ;}