.u-section-1 {background-image: url("images/monogramfoldal.jpg"); min-height: 100vh; background-position: 50% 50%} 

@media (max-width: 1199px){ .u-section-1 {min-height: 500px} }

@media (max-width: 991px){ .u-section-1 {min-height: 399px} }

@media (max-width: 767px){ .u-section-1 {min-height: 314px} }

@media (max-width: 575px){ .u-section-1 {min-height: 220px} }