Add support for dynamic viewport height (#36272)

Co-authored-by: l <eh.chahkiev@smartics.ru>

app/javascript/styles/mastodon/admin.scss

@@ -13,6 +13,7 @@ $content-width: 840px;
   box-sizing: border-box;
   width: 100%;
   min-height: 100vh;
+  min-height: 100dvh;
   padding: env(safe-area-inset-top) env(safe-area-inset-right)
     env(safe-area-inset-bottom) env(safe-area-inset-left);
 
@@ -25,6 +26,7 @@ $content-width: 840px;
 
   .sidebar-wrapper {
     min-height: 100vh;
+    min-height: 100dvh;
     overflow: hidden;
     pointer-events: none;
     flex: 1 1 auto;