diff --git a/core/modules/simpletest/css/simpletest.module.css b/core/modules/simpletest/css/simpletest.module.css
index c0079b6..d2c594c 100644
--- a/core/modules/simpletest/css/simpletest.module.css
+++ b/core/modules/simpletest/css/simpletest.module.css
@@ -1,9 +1,12 @@
+/**
+ * @file
+ * Test Table.
+ */
 
-/* Test Table */
-#simpletest-form-table th.select-all {
+.simpletest-test-form .select-all {
   width: 1em;
 }
-th.simpletest-test-label {
+.simpletest-test-label {
   width: 40%;
 }
 
@@ -12,82 +15,37 @@ th.simpletest-test-label {
   cursor: pointer;
   width: 1em;
 }
-.simpletest-group-label label {
-  display: inline;
-  font-weight: bold;
-}
 .simpletest-test-label label {
-  margin-left: 1em; /* LTR */
+  margin: 0 0 0 1em; /* LTR */
+}
+[dir="rtl"] .simpletest-test-label label {
+  margin: 0 1em 0 0; /* RTL */
 }
 .simpletest-test-description .description {
   margin: 0;
 }
-#simpletest-form-table tr td {
-  background-color: white;
-  color: #494949;
-}
-#simpletest-form-table tr.simpletest-group td {
+.simpletest-form-table .simpletest-group td {
   background-color: #edf5fa;
   color: #494949;
 }
 
-table#simpletest-form-table tr.simpletest-group label {
+.simpletest-test-form .simpletest-group label {
   display: inline;
 }
 
-div.message > div.item-list {
-  font-weight: normal;
-}
-
-div.simpletest-pass {
-  color: #33a333;
-}
-.simpletest-fail {
-  color: #981010;
-}
-
-tr.simpletest-pass,
-tr.simpletest-pass.odd {
-  background-color: #b6ffb6;
-}
-tr.simpletest-pass.even {
-  background-color: #9bff9b;
-}
-tr.simpletest-fail,
-tr.simpletest-fail.odd {
-  background-color: #ffc9c9;
-}
-tr.simpletest-fail.even {
-  background-color: #ffacac;
-}
-tr.simpletest-exception,
-tr.simpletest-exception.odd {
-  background-color: #f4ea71;
-}
-tr.simpletest-exception.even {
-  background-color: #f5e742;
-}
-tr.simpletest-debug,
-tr.simpletest-debug.odd {
-  background-color: #eee;
-}
-tr.simpletest-debug.even {
-  background-color: #fff;
-}
-
-a.simpletest-collapse {
+.simpletest-collapse {
   height: 0;
   width: 0;
   top: -99em;
   position: absolute;
 }
-a.simpletest-collapse:focus,
-a.simpletest-collapse:hover {
-  font-size: 80%;
-  top: 0px;
-  height: auto;
-  width: auto;
+.simpletest-collapse:focus,
+.simpletest-collapse:hover {
   overflow: visible;
   position: relative;
+  top: 0;
   z-index: 1000;
+  font-size: 80%;
+  height: auto;
+  width: auto;
 }
diff --git a/core/modules/simpletest/src/Form/SimpletestTestForm.php b/core/modules/simpletest/src/Form/SimpletestTestForm.php
index c325a8a..4a778a6 100644
--- a/core/modules/simpletest/src/Form/SimpletestTestForm.php
+++ b/core/modules/simpletest/src/Form/SimpletestTestForm.php
@@ -114,6 +114,11 @@ public function buildForm(array $form, FormStateInterface $form_state) {
           'simpletest/drupal.simpletest',
         ),
       ),
+      '#attributes' => array(
+        'class' => array(
+          'simpletest-form-table',
+        ),
+      ),
     );
 
     // Define the images used to expand/collapse the test groups.
diff --git a/core/themes/seven/css/components/tables.css b/core/themes/seven/css/components/tables.css
index 3bdf7cc..bb539aa 100644
--- a/core/themes/seven/css/components/tables.css
+++ b/core/themes/seven/css/components/tables.css
@@ -48,6 +48,10 @@ tbody tr.color-error:hover,
 tbody tr.color-error:focus {
   background: #fcf4f2;
 }
+tbody tr.color-success:hover,
+tbody tr.color-success:focus {
+  background: #77b259;
+}
 td,
 th {
   vertical-align: middle;
@@ -74,6 +78,8 @@ th > a:after {
   left: 0;
   right: 0;
   border-bottom: 2px solid transparent;
+  -moz-transition: all 0.1s;
+  -o-transition: all 0.1s;
   -webkit-transition: all 0.1s;
   transition: all 0.1s;
 }