.contact_us_container #map_container{
  width: 100%;min-width: 520px;height: 520px;
}
.img_box{
  width: 44px;height: 44px;position: relative;
}
.img_box img{
  width: 100%;height: 100%;display: block;
  position: absolute;top: 50%;left: 50%;
  -webkit-transform: translate(-50%,-50%);
          transform: translate(-50%,-50%);
}