diff --git a/core/themes/seven/css/layout/node-add.css b/core/themes/seven/css/layout/node-add.css
deleted file mode 100644
index 22faf33..0000000
--- a/core/themes/seven/css/layout/node-add.css
+++ /dev/null
@@ -1,17 +0,0 @@
-/**
- * Widescreen
- *
- * Both of the following media queries must *exactly* match what is in
- * node.module.css. This is rather crazy.
- *
- * @todo Figure out how to reduce media query duplication across files
- *       and modules. Layout styles only allowed in themes?
- */
-@media
-  screen and (min-width: 780px),
-  (orientation: landscape) and (min-device-height: 780px) {
-  .node-form-layout .messages {
-    margin-top: 1em;
-    margin-bottom: 1em;
-  }
-}
diff --git a/core/themes/seven/seven.theme b/core/themes/seven/seven.theme
index 91c03e6..1c575a4 100644
--- a/core/themes/seven/seven.theme
+++ b/core/themes/seven/seven.theme
@@ -8,21 +8,6 @@
 use Drupal\Core\Form\FormStateInterface;
 
 /**
- * Implements hook_preprocess_HOOK() for HTML document templates.
- */
-function seven_preprocess_html(&$variables) {
-  // If on a node add or edit page, add a node-layout class.
-  $path_args = explode('/', \Drupal::request()->getPathInfo());
-  if ($suggestions = theme_get_suggestions($path_args, 'page', '-')) {
-    foreach ($suggestions as $suggestion) {
-      if ($suggestion === 'page-node-edit' || strpos($suggestion, 'page-node-add') !== FALSE) {
-        $variables['attributes']['class'][] = 'node-form-layout';
-      }
-    }
-  }
-}
-
-/**
  * Implements hook_pre_render_HOOK() for menu-local-tasks templates.
  *
  * Use preprocess hook to set #attached to child elements