.header .cont .head { background:url(http://pooyafile.ir/wp-content/uploads/2017/12/pooyafile.ir_.png); }
@media screen and (max-width:768px){
.header .cont .head { background-image:url(https://pooyafile.ir/wp-content/themes/daneshfile-edd/img/head-res.jpg);
}
@media screen and (max-width:768px){
.header .cont .head { background-image:url(http://pooyafile.ir/wp-content/uploads/2017/12/pooyafile.ir_.png);
}