#grid-image-1 {
    background-image: url(../images/work/hitachi/1.png);
    background-size: contain;
  }
  
  #grid-image-2 {
    background-image: url(../images/work/hitachi/2.png);
    background-size: contain;
  }
  
  #grid-image-3 {
    background-image: url(../images/work/hitachi/3.png);
    background-size: contain;
  }
  
  #grid-image-4 {
    background-image: url(../images/work/hitachi/4.png);
  }
  
  #grid-image-5 {
    background-image: url(../images/work/hitachi/5.png);
  }
  
  #grid-image-6 {
    background-image: url(../images/work/hitachi/6.png);
  }
  
  #grid-image-7 {
    background-image: url(../images/work/hitachi/7.png);
  }
  

@media only screen and (max-width: 1400px){
    #grid-image-4,
    #grid-image-5,
    #grid-image-6 {
      background-size: 100%;
      grid-column: span 6 / auto;
    }
}

@media only screen and (max-width: 520px){
  #grid-image-1,
  #grid-image-2 {
    background-size: 100%;
    grid-column: span 6 / auto;
    grid-row: span 2 / auto;
  }
}