@media (min-width: 900px) {
  body.has-sidebar-left .site-grid {
    /* Ändern Sie den Wert '20rem' (Standard) auf Ihre Wunschbreite, z.B. 25rem oder 300px */
    grid-template-columns: [full-start] minmax(0, 1fr) [main-start] minmax(0, 210px) repeat(2, minmax(0, 15rem)) minmax(0, 30rem) [main-end] minmax(0, 1fr) [full-end];
  }

.container-header {
    background-image: url('/images/header_bg.png') !important;
    background-position: center center;
    background-repeat: no-repeat;
   background-size: cover;
   padding: 25px;
   }
  .container-header .navbar-brand {
    margin-left: auto;
    margin-right: auto;
    text-align: center;
    justify-content: center;
}
  body {
    background-image: url('/images/wb-gb.jpg');
    background-repeat: no-repeat;
    background-size: cover;
    background-attachment: fixed;
    background-position: center;
}

  }