chore: add css for gatekeeper

Author: arunjaindev

src/css/base.scss

@@ -5122,3 +5122,27 @@ details[open] {
         }
     }
 }
+
+.dc__place-self-center {
+    place-self: center;
+}
+
+.twelve-col-layout {
+    grid-template-columns: repeat(12, 1fr);
+}
+
+.dc__mxw-50-per {
+    max-width: 50%;
+}
+
+.mh-100vh {
+    min-height: 100vh;
+}
+
+.mh-170 {
+    min-height: 170px;
+}
+
+.mw-76 {
+    min-width: 76px;
+}

src/css/formulae.scss

@@ -593,3 +593,15 @@ $color-suffix: 00;
 .steps-with-trail--normal {
     @include steps-with-trail(20px, 24px, 16px, 40px)
 }
+
+@for $i from 1 through 12 {
+    @for $j from 1 through 12 {
+        .grid-col-#{$i}-#{$j} {
+            grid-column: #{$i} / span #{$j};
+        }
+    }
+
+    .grid-col-#{$i}--end {
+        grid-column: #{$i} / -1;
+    }
+}

src/css/themeUtils.scss

@@ -159,6 +159,10 @@
         &--bottom {
             border-bottom: 1px solid var(--border-secondary);
         }
+
+        &--left {
+            border-left: 1px solid var(--border-secondary);
+        }
     }
 
     &__secondary-translucent {
@@ -214,4 +218,4 @@
         min-height: 16px;
         background-color: var(--divider-secondary-translucent);
     }
-}
+}