edit css thumbnail

admin/css/dashboard1.css

+body {
+    font-size: .875rem;
+  }
+
+  .btn {
+    margin-right: 5px;
+  }
+  
+  .feather {
+    width: 16px;
+    height: 16px;
+    vertical-align: text-bottom;
+  }
+  
+  /*
+   * Sidebar
+   */
+  
+  .sidebar {
+    position: fixed;
+    top: 0;
+    bottom: 0;
+    left: 0;
+    z-index: 100; /* Behind the navbar */
+    padding: 0;
+    box-shadow: inset -1px 0 0 rgba(0, 0, 0, .1);
+  }
+  
+  .sidebar-sticky {
+    position: -webkit-sticky;
+    position: sticky;
+    top: 48px; /* Height of navbar */
+    height: calc(100vh - 48px);
+    padding-top: 48px;
+    overflow-x: hidden;
+    overflow-y: auto; /* Scrollable contents if viewport is shorter than content. */
+  }
+  
+  .sidebar .nav-link {
+    font-weight: 500;
+    color: #333;
+  }
+  
+  .sidebar .nav-link .feather {
+    margin-right: 4px;
+    color: #999;
+  }
+  
+  .sidebar .nav-link.active {
+    color: #007bff;
+  }
+  
+  .sidebar .nav-link:hover .feather,
+  .sidebar .nav-link.active .feather {
+    color: inherit;
+  }
+  
+  .sidebar-heading {
+    font-size: .75rem;
+    text-transform: uppercase;
+  }
+  
+  /*
+   * Navbar
+   */
+  
+  .navbar-brand {
+    padding-top: .75rem;
+    padding-bottom: .75rem;
+    font-size: 1rem;
+    background-color: rgba(0, 0, 0, .25);
+    box-shadow: inset -1px 0 0 rgba(0, 0, 0, .25);
+  }
+  
+  .navbar .form-control {
+    padding: .75rem 1rem;
+    border-width: 0;
+    border-radius: 0;
+  }
+  
+  .form-control-dark {
+    color: #fff;
+    background-color: rgba(255, 255, 255, .1);
+    border-color: rgba(255, 255, 255, .1);
+  }
+  
+  .form-control-dark:focus {
+    border-color: transparent;
+    box-shadow: 0 0 0 3px rgba(255, 255, 255, .25);
+  }
+
+  .navbar-collapse .nav-link {
+    color: #fff;
+  }
+
+  .navbar-collapse .nav-link.active {
+    color: #007bff;
+  }
+
+  .navbar-collapse .nav-link .feather {
+    margin-right: 4px;
+    color: #999;
+  }
+
+  .navbar-collapse .nav-link:hover .feather,
+  .navbar-collapse .nav-link.active .feather {
+    color: inherit;
+  }
+  
+  .small-nav-dark {
+    background-color: #343a40;
+    box-shadow: inset 0px 0 0 rgba(0, 0, 0, 0);
+  }
+
+  .unstyled-button {
+    border: none;
+    background: none;
+  }
+  
+  /*
+   * Utilities
+   */
+  
+  .border-top { border-top: 1px solid #e5e5e5; }
+  .border-bottom { border-bottom: 1px solid #e5e5e5; }
+
+  diva {
+    line-height: 200px;
+  }
+  
+  img {
+    max-width: 200px;
+    max-height: 200px;
+    padding: 5px;
+    vertical-align: middle;
+    text-align: center;
+  }
+
+  @supports (object-fit: cover) {
+    img {
+      width: 200px;
+      height: 200px;
+      object-fit: cover;
+      position: absolute;
+      left: 20%;
+    }
+  }
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