.checkerboard {
        background-color: #1e293b;
        background-image: 
          linear-gradient(45deg, #0f172a 25%, transparent 25%), 
          linear-gradient(-45deg, #0f172a 25%, transparent 25%), 
          linear-gradient(45deg, transparent 75%, #0f172a 75%), 
          linear-gradient(-45deg, transparent 75%, #0f172a 75%);
        background-size: 20px 20px;
        background-position: 0 0, 0 10px, 10px -10px, -10px 0px;
      }