@media only screen and (max-width : 830px) and (min-width : 601px){
  #top-bg{
    min-height: 45vw;
    height: 45vw;
  }

}

@media only screen and (max-width : 600px){
  #top-bg{
    min-height: 55vw;
    height: 55vw;
  }

  #top-title{
    font-size: 300%;
  }
}