diff --git a/core/includes/ajax.inc b/core/includes/ajax.inc
index 45bb706..1edd871 100644
--- a/core/includes/ajax.inc
+++ b/core/includes/ajax.inc
@@ -631,7 +631,7 @@ function ajax_pre_render_element($element) {
       // If the element is a (non-image) button, its name may not identify it
       // uniquely, in which case a match on value is also needed.
       // @see _form_button_was_clicked()
-      if (isset($element['#button_type']) && empty($element['#has_garbage_value'])) {
+      if (!empty($element['#is_button']) && empty($element['#has_garbage_value'])) {
         $settings['submit']['_triggering_element_value'] = $element['#value'];
       }
     }
diff --git a/core/includes/form.inc b/core/includes/form.inc
index 226d4a6..ea5c4c6 100644
--- a/core/includes/form.inc
+++ b/core/includes/form.inc
@@ -1169,7 +1169,7 @@ function drupal_validate_form($form_id, &$form, &$form_state) {
     // allow the value of the clicked button to be retained in its normal
     // $form_state['values'] locations, even if these locations are not included
     // in #limit_validation_errors.
-    if (isset($form_state['triggering_element']['#button_type'])) {
+    if (!empty($form_state['triggering_element']['#is_button'])) {
       $button_value = $form_state['triggering_element']['#value'];
 
       // Like all input controls, the button value may be in the location
@@ -1947,7 +1947,7 @@ function form_builder($form_id, &$element, &$form_state) {
     }
 
     // Special processing if the triggering element is a button.
-    if (isset($form_state['triggering_element']['#button_type'])) {
+    if (!empty($form_state['triggering_element']['#is_button'])) {
       // Because there are several ways in which the triggering element could
       // have been determined (including from input variables set by JavaScript
       // or fallback behavior implemented for IE), and because buttons often
@@ -2083,7 +2083,7 @@ function _form_builder_handle_input_element($form_id, &$element, &$form_state) {
     // If the form was submitted by the browser rather than via Ajax, then it
     // can only have been triggered by a button, and we need to determine which
     // button within the constraints of how browsers provide this information.
-    if (isset($element['#button_type'])) {
+    if (!empty($element['#is_button'])) {
       // All buttons in the form need to be tracked for
       // form_state_values_clean() and for the form_builder() code that handles
       // a form submission containing no button information in $_POST.
@@ -3161,6 +3161,12 @@ function form_pre_render_conditional_form_element($element) {
  * Processes a form button element.
  */
 function form_process_button($element, $form_state) {
+  // Automatically take over the button's array key as #button_type, unless
+  // #button_type has been manually specified.
+  // @see theme_button()
+  if (!isset($element['#button_type'])) {
+    $element['#button_type'] = end($element['#array_parents']);
+  }
   // If this is a button intentionally allowing incomplete form submission
   // (e.g., a "Previous" or "Add another item" button), then also skip
   // client-side validation.
@@ -3250,6 +3256,13 @@ function form_process_checkboxes($element) {
  */
 function form_process_actions($element, &$form_state) {
   $element['#attributes']['class'][] = 'form-actions';
+  // The primary actions in a form may be denoted by setting #primary to TRUE,
+  // in order to facilitate specialized button styling in themes.
+  // @todo Consider to remove actions containers for alternate form actions or
+  //   introduce a suitable replacement container for them.
+  if (!empty($element['#primary'])) {
+    $element['#attributes']['class'][] = 'primary';
+  }
   return $element;
 }
 
@@ -3936,7 +3949,13 @@ function theme_button($variables) {
   $element['#attributes']['type'] = 'submit';
   element_set_attributes($element, array('id', 'name', 'value'));
 
-  $element['#attributes']['class'][] = 'form-' . $element['#button_type'];
+  $element['#attributes']['class'][] = 'button';
+  if (!empty($element['#button_type'])) {
+    $element['#attributes']['class'][] = 'button-' . $element['#button_type'];
+  }
+  // @todo Various JavaScript depends on this button class.
+  $element['#attributes']['class'][] = 'form-submit';
+
   if (!empty($element['#attributes']['disabled'])) {
     $element['#attributes']['class'][] = 'form-button-disabled';
   }
@@ -3965,7 +3984,13 @@ function theme_image_button($variables) {
     $element['#attributes']['title'] = $element['#title'];
   }
 
-  $element['#attributes']['class'][] = 'form-' . $element['#button_type'];
+  $element['#attributes']['class'][] = 'button';
+  if (!empty($element['#button_type'])) {
+    $element['#attributes']['class'][] = 'button-' . $element['#button_type'];
+  }
+  // @todo Various JavaScript depends on this button class.
+  $element['#attributes']['class'][] = 'form-submit';
+
   if (!empty($element['#attributes']['disabled'])) {
     $element['#attributes']['class'][] = 'form-button-disabled';
   }
diff --git a/core/lib/Drupal/Core/Entity/EntityFormController.php b/core/lib/Drupal/Core/Entity/EntityFormController.php
index 2e9daac..d348ef1 100644
--- a/core/lib/Drupal/Core/Entity/EntityFormController.php
+++ b/core/lib/Drupal/Core/Entity/EntityFormController.php
@@ -88,17 +88,13 @@ public function form(array $form, array &$form_state, EntityInterface $entity) {
    */
   protected function actionsElement(array $form, array &$form_state) {
     $element = $this->actions($form, $form_state);
+    $element['#type'] = 'actions';
+    // Indicate that these are the primary actions of the form.
+    $element['#primary'] = TRUE;
 
     // We cannot delete an entity that has not been created yet.
     if ($this->getEntity($form_state)->isNew()) {
-      unset($element['delete']);
-    }
-    elseif (isset($element['delete'])) {
-      // Move the delete action as last one, unless weights are explicitly
-      // provided.
-      $delete = $element['delete'];
-      unset($element['delete']);
-      $element['delete'] = $delete;
+      $element['delete']['#access'] = FALSE;
     }
 
     $count = 0;
@@ -109,10 +105,6 @@ protected function actionsElement(array $form, array &$form_state) {
       );
     }
 
-    if (!empty($element)) {
-      $element['#type'] = 'actions';
-    }
-
     return $element;
   }
 
@@ -134,6 +126,7 @@ protected function actions(array $form, array &$form_state) {
       ),
       'delete' => array(
         '#value' => t('Delete'),
+        '#weight' => 50,
         // No need to validate the form when deleting the entity.
         '#submit' => array(
           array($this, 'delete'),
diff --git a/core/modules/system/lib/Drupal/system/Tests/Form/ElementTest.php b/core/modules/system/lib/Drupal/system/Tests/Form/ElementTest.php
index 621578c..bec18fb 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Form/ElementTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Form/ElementTest.php
@@ -92,4 +92,19 @@ function testOptions() {
       )));
     }
   }
+
+  /**
+   * Tests button classes.
+   */
+  function testButtonClasses() {
+    $this->drupalGet('form-test/button-class');
+    // Just contains(@class, "button") won't do because then
+    // "button-foo" would contain "button". Instead, check
+    // " button ". Make sure it matches in the beginning and the end too
+    // by adding a space before and after.
+    $this->assertEqual(2, count($this->xpath('//*[contains(concat(" ", @class, " "), " button ")]')));
+    $this->assertEqual(1, count($this->xpath('//*[contains(concat(" ", @class, " "), " button-foo ")]')));
+    $this->assertEqual(1, count($this->xpath('//*[contains(concat(" ", @class, " "), " button-delete ")]')));
+  }
+
 }
diff --git a/core/modules/system/system.module b/core/modules/system/system.module
index 843ed78..f8ae55d 100644
--- a/core/modules/system/system.module
+++ b/core/modules/system/system.module
@@ -300,7 +300,7 @@ function system_element_info() {
   $types['submit'] = array(
     '#input' => TRUE,
     '#name' => 'op',
-    '#button_type' => 'submit',
+    '#is_button' => TRUE,
     '#executes_submit_callback' => TRUE,
     '#limit_validation_errors' => FALSE,
     '#process' => array('form_process_button', 'ajax_process_form'),
@@ -309,7 +309,7 @@ function system_element_info() {
   $types['button'] = array(
     '#input' => TRUE,
     '#name' => 'op',
-    '#button_type' => 'submit',
+    '#is_button' => TRUE,
     '#executes_submit_callback' => FALSE,
     '#limit_validation_errors' => FALSE,
     '#process' => array('form_process_button', 'ajax_process_form'),
@@ -317,7 +317,7 @@ function system_element_info() {
   );
   $types['image_button'] = array(
     '#input' => TRUE,
-    '#button_type' => 'submit',
+    '#is_button' => TRUE,
     '#executes_submit_callback' => TRUE,
     '#limit_validation_errors' => FALSE,
     '#process' => array('form_process_button', 'ajax_process_form'),
@@ -551,6 +551,7 @@ function system_element_info() {
   $types['actions'] = array(
     '#theme_wrappers' => array('container'),
     '#process' => array('form_process_actions', 'form_process_container'),
+    '#primary' => FALSE,
     '#weight' => 100,
   );
 
diff --git a/core/modules/system/tests/modules/form_test/form_test.module b/core/modules/system/tests/modules/form_test/form_test.module
index 03b7cb8..db0eb8c 100644
--- a/core/modules/system/tests/modules/form_test/form_test.module
+++ b/core/modules/system/tests/modules/form_test/form_test.module
@@ -307,6 +307,12 @@ function form_test_menu() {
     'page arguments' => array('form_test_required_attribute'),
     'access callback' => TRUE,
   );
+  $items['form-test/button-class'] = array(
+    'title' => 'Button class testing',
+    'page callback' => 'drupal_get_form',
+    'page arguments' => array('form_test_button_class'),
+    'access callback' => TRUE,
+  );
 
   return $items;
 }
@@ -2310,3 +2316,19 @@ function form_test_html_id($form, &$form_state) {
   );
   return $form;
 }
+
+/**
+ * Builds a simple form to test form button classes.
+ */
+function form_test_button_class($form, &$form_state) {
+  $form['button'] = array(
+    '#type' => 'button',
+    '#value' => 'test',
+    '#button_type' => 'foo',
+  );
+  $form['delete'] = array(
+    '#type' => 'button',
+    '#value' => 'Delete',
+  );
+  return $form;
+}
diff --git a/core/modules/user/lib/Drupal/user/ProfileFormController.php b/core/modules/user/lib/Drupal/user/ProfileFormController.php
index d2a7e81..5584e63 100644
--- a/core/modules/user/lib/Drupal/user/ProfileFormController.php
+++ b/core/modules/user/lib/Drupal/user/ProfileFormController.php
@@ -21,16 +21,10 @@ protected function actions(array $form, array &$form_state) {
     $element = parent::actions($form, $form_state);
     $account = $this->getEntity($form_state);
 
-    // @todo Actually the cancel action can be assimilated to the delete one: we
-    // should alter it instead of providing a new one.
-    unset($element['delete']);
-
-    $element['cancel'] = array(
-      '#type' => 'submit',
-      '#value' => t('Cancel account'),
-      '#submit' => array('user_edit_cancel_submit'),
-      '#access' => $account->uid > 1 && (($account->uid == $GLOBALS['user']->uid && user_access('cancel account')) || user_access('administer users')),
-    );
+    $element['delete']['#type'] = 'submit';
+    $element['delete']['#value'] = t('Cancel account');
+    $element['delete']['#submit'] = array('user_edit_cancel_submit');
+    $element['delete']['#access'] = $account->uid > 1 && (($account->uid == $GLOBALS['user']->uid && user_access('cancel account')) || user_access('administer users'));
 
     return $element;
   }
diff --git a/core/modules/views/views_ui/admin.inc b/core/modules/views/views_ui/admin.inc
index 5b0ae41..a37297f 100644
--- a/core/modules/views/views_ui/admin.inc
+++ b/core/modules/views/views_ui/admin.inc
@@ -2303,7 +2303,7 @@ function views_fetch_fields($base, $type, $grouping = FALSE, $sub_type = NULL) {
  */
 function views_ui_form_button_was_clicked($element, &$form_state) {
   $process_input = empty($element['#disabled']) && ($form_state['programmed'] || ($form_state['process_input'] && (!isset($element['#access']) || $element['#access'])));
-  if ($process_input && !isset($form_state['triggering_element']) && isset($element['#button_type']) && isset($form_state['input'][$element['#name']]) && isset($element['#values']) && in_array($form_state['input'][$element['#name']], $element['#values'], TRUE)) {
+  if ($process_input && !isset($form_state['triggering_element']) && !empty($element['#is_button']) && isset($form_state['input'][$element['#name']]) && isset($element['#values']) && in_array($form_state['input'][$element['#name']], $element['#values'], TRUE)) {
     $form_state['triggering_element'] = $element;
   }
   return $element;
diff --git a/core/themes/bartik/css/style-rtl.css b/core/themes/bartik/css/style-rtl.css
index d95d66b..3b52583 100644
--- a/core/themes/bartik/css/style-rtl.css
+++ b/core/themes/bartik/css/style-rtl.css
@@ -146,8 +146,7 @@ ul.tips {
 
 /* ----------------- Buttons ------------------ */
 
-input.form-submit,
-a.button {
+.button {
   margin-right: 0;
   margin-left: 0.6em;
 }
diff --git a/core/themes/bartik/css/style.css b/core/themes/bartik/css/style.css
index 94ac775..2a70405 100644
--- a/core/themes/bartik/css/style.css
+++ b/core/themes/bartik/css/style.css
@@ -1096,8 +1096,7 @@ div.password-confirm {
 
 /* ---------------- Buttons    ---------------- */
 
-input.form-submit,
-a.button {
+.button {
   background: #fff url(../images/buttons.png) 0 0 repeat-x;
   border: 1px solid #e4e4e4;
   border-bottom: 1px solid #b4b4b4;
@@ -1113,11 +1112,11 @@ a.button {
   padding: 4px 17px;
   border-radius: 15px;
 }
-a.button:link,
-a.button:visited,
-a.button:hover,
-a.button:focus,
-a.button:active {
+.button:link,
+.button:visited,
+.button:hover,
+.button:focus,
+.button:active {
   text-decoration: none;
   color: #5a5a5a;
 }
diff --git a/core/themes/seven/images/buttons.png b/core/themes/seven/images/buttons.png
deleted file mode 100644
index 0a89f98..0000000
--- a/core/themes/seven/images/buttons.png
+++ /dev/null
@@ -1,3 +0,0 @@
-�PNG
-
-
IHDR
�xS�3�
�IDATx^���u
E��"���B1D�_וּ��)��@����-@�a
�aX@��D�0���0, c7�d�@�a
��0, c?
"����2� °��]
D��o�d�+@�a
�aX@�>D��O�d�#@�a
�aX@�.
"v���D��w�d�aX@�."��[��2� °����0, c�"��9@�a
�d����d�@����s��2� °��=�0, ð��2� °��=�0, c�"��@�a
;�0, ð��2�0, ð��2� °��2����2�0, ð��2�0, ð��2v °��2��	@�a
�d��{�d�aX@��D�aX@�a
�aX@�7����ZIEND�B`�
\ No newline at end of file
diff --git a/core/themes/seven/style-rtl.css b/core/themes/seven/style-rtl.css
index 3276ce8..f039008 100644
--- a/core/themes/seven/style-rtl.css
+++ b/core/themes/seven/style-rtl.css
@@ -127,8 +127,7 @@ body div.form-type-checkbox div.description {
   margin-left: 0;
   margin-right: 1.5em;
 }
-input.form-submit,
-a.button {
+.button {
   margin-left: 1em;
   margin-right: 0;
 }
diff --git a/core/themes/seven/style.css b/core/themes/seven/style.css
index 575c91b..bea0931 100644
--- a/core/themes/seven/style.css
+++ b/core/themes/seven/style.css
@@ -615,8 +615,7 @@ body div.form-type-radio div.description,
 body div.form-type-checkbox div.description {
   margin-left: 1.5em; /* LTR */
 }
-input.form-submit,
-a.button {
+.button {
   cursor: pointer;
   padding: 4px 17px;
   margin-bottom: 1em;
@@ -630,29 +629,26 @@ a.button {
   border-bottom: 1px solid #b4b4b4;
   border-left-color: #d2d2d2;
   border-right-color: #d2d2d2;
-  background: url(images/buttons.png) 0 0 repeat-x;
+  background-color: #e4e4e4;
   border-radius: 20px;
 }
-a.button:link,
-a.button:visited,
-a.button:hover,
-a.button:active {
+.button:link,
+.button:visited,
+.button:hover,
+.button:active {
   text-decoration: none;
 }
-input.form-submit:hover,
-input.form-submit:focus,
-a.button:hover,
-a.button:focus {
-  background-position: 0 -40px;
+.button:focus,
+.button:hover {
+  background-color: #c0c0c0;
   border: 1px solid #bebebe;
   border-left-color: #afafaf;
   border-right-color: #afafaf;
   border-bottom-color: #9b9b9b;
   color: #2e2e2e;
 }
-input.form-submit:active,
-a.button:active {
-  background-position: 0 -80px;
+.button:active {
+  background-color: #565656;
   border: 1px solid #333;
   border-left-color: #222;
   border-right-color: #222;
@@ -660,9 +656,26 @@ a.button:active {
   color: #fff;
   text-shadow: #222 0 -1px 0;
 }
+.form-actions.primary .button:first-child {
+  background-color: #9dcae7;
+  border: 1px solid #8eB7cd;
+  border-bottom-color: #7691a2;
+  color: #133B54;
+}
+.form-actions.primary .button:first-child:focus,
+.form-actions.primary .button:first-child:hover {
+  background-color: #73b3dd;
+  border: 1px solid #6ea3bf;
+  border-bottom-color: #4680a0;
+}
+.form-actions.primary .button:first-child:active {
+  background-color: #3981b1;
+  border: 1px solid #36647c;
+  border-bottom-color: #284657;
+}
 input.form-button-disabled,
 input.form-button-disabled:active {
-  background: #eee none;
+  background-color: #eee;
   border-color: #eee;
   text-shadow: none;
   color: #999;
@@ -795,6 +808,11 @@ div.filter-options select {
   padding: 0;
 }
 
+/* Form actions */
+.form-actions {
+  margin-top: 1em;
+}
+
 /**
  * System.
  */