diff --git a/core/.stylelintrc.json b/core/.stylelintrc.json
new file mode 100644
index 0000000..322fad0
--- /dev/null
+++ b/core/.stylelintrc.json
@@ -0,0 +1,43 @@
+{
+  "extends": "stylelint-config-standard",
+  "plugins": [
+    "stylelint-no-browser-hacks/lib"
+  ],
+  "rules": {
+    "at-rule-empty-line-before": null,
+    "block-no-empty": null,
+    "color-hex-case": null,
+    "color-hex-length": null,
+    "comment-empty-line-before": null,
+    "declaration-block-no-duplicate-properties": null,
+    "declaration-block-no-redundant-longhand-properties": null,
+    "declaration-block-no-shorthand-property-overrides": null,
+    "declaration-block-trailing-semicolon": null,
+    "declaration-colon-space-after": null,
+    "function-comma-space-after": null,
+    "function-linear-gradient-no-nonstandard-direction": null,
+    "function-name-case": null,
+    "function-whitespace-after": null,
+    "length-zero-no-unit": null,
+    "no-empty-source": null,
+    "no-unknown-animations": true,
+    "number-leading-zero": null,
+    "number-no-trailing-zeros": null,
+    "plugin/no-browser-hacks": [true, {
+      "browsers": [
+        "last 2 versions",
+        "ie >=8"
+      ]
+    }],
+    "property-no-unknown": null,
+    "rule-empty-line-before": null,
+    "selector-pseudo-element-colon-notation": null,
+    "selector-type-no-unknown": null,
+    "shorthand-property-no-redundant-values": null,
+    "unit-whitelist": ["deg", "em", "ex", "ms", "rem", "%", "s", "px"]
+  },
+  "ignoreFiles": [
+    "assets/vendor/**/*.css",
+    "tests/Drupal/Tests/Core/Asset/css_test_files/**/*.css"
+  ]
+}
diff --git a/core/misc/dropbutton/dropbutton.css b/core/misc/dropbutton/dropbutton.css
index 5990514..8b8709d 100644
--- a/core/misc/dropbutton/dropbutton.css
+++ b/core/misc/dropbutton/dropbutton.css
@@ -17,14 +17,14 @@
   position: relative;
 }
 
-@media screen and (max-width:600px) {
+@media screen and (max-width: 600px) {
   .js .dropbutton-wrapper {
     width: 100%;
   }
 }
 
 /* Splitbuttons */
-@media screen and (min-width:600px) {
+@media screen and (min-width: 600px) {
   .form-actions .dropbutton-wrapper {
     float: left; /* LTR */
   }
diff --git a/core/misc/print.css b/core/misc/print.css
index 6e69a3b..586d332 100644
--- a/core/misc/print.css
+++ b/core/misc/print.css
@@ -17,7 +17,7 @@ th {
 tr:nth-child(odd) {
   background-color: #ddd;
 }
-tr:nth-child(even){
+tr:nth-child(even) {
   background-color: #fff;
 }
 td {
diff --git a/core/misc/vertical-tabs.css b/core/misc/vertical-tabs.css
index ec5d3c1..fc83da5 100644
--- a/core/misc/vertical-tabs.css
+++ b/core/misc/vertical-tabs.css
@@ -8,8 +8,8 @@
   border: 1px solid #ccc;
 }
 [dir="rtl"] .vertical-tabs {
-   margin-left: 0;
-   margin-right: 15em;
+  margin-left: 0;
+  margin-right: 15em;
 }
 .vertical-tabs__menu {
   float: left; /* LTR */
diff --git a/core/modules/block/css/block.admin.css b/core/modules/block/css/block.admin.css
index 7fde3d7..16bee33 100644
--- a/core/modules/block/css/block.admin.css
+++ b/core/modules/block/css/block.admin.css
@@ -24,7 +24,7 @@ a.block-demo-backlink:visited {
   font-family: "Lucida Grande", Verdana, sans-serif;
   font-size: small;
   line-height: 20px;
-  left: 20px; /*LTR*/
+  left: 20px; /* LTR */
   padding: 5px 10px;
   position: fixed;
   z-index: 499;
diff --git a/core/modules/ckeditor/css/ckeditor-iframe.css b/core/modules/ckeditor/css/ckeditor-iframe.css
index 8996334..c34a683 100644
--- a/core/modules/ckeditor/css/ckeditor-iframe.css
+++ b/core/modules/ckeditor/css/ckeditor-iframe.css
@@ -16,7 +16,9 @@ body {
   }
 }
 
-ol, ul, dl {
+ol,
+ul,
+dl {
   /* Preserved spaces for list items with text direction other than the list.
    * (CKEditor issues #6249,#8049) */
   padding: 0 40px;
diff --git a/core/modules/ckeditor/css/ckeditor.admin.css b/core/modules/ckeditor/css/ckeditor.admin.css
index 8b771c7..cfbeae0 100644
--- a/core/modules/ckeditor/css/ckeditor.admin.css
+++ b/core/modules/ckeditor/css/ckeditor.admin.css
@@ -6,8 +6,6 @@
  * "moono".
  */
 
-
-
 .ckeditor-toolbar {
   border: 1px solid #b6b6b6;
   padding: 0.1667em 0.1667em 0.08em;
@@ -119,7 +117,7 @@
   margin: 3px 6px;
   padding: 3px;
 }
-.ckeditor-toolbar-configuration .fieldset-description{
+.ckeditor-toolbar-configuration .fieldset-description {
   margin-bottom: 1em;
 }
 .ckeditor-toolbar-disabled .ckeditor-toolbar-available,
diff --git a/core/modules/image/css/editors/image.theme.css b/core/modules/image/css/editors/image.theme.css
index cb0c7f9..5946458 100644
--- a/core/modules/image/css/editors/image.theme.css
+++ b/core/modules/image/css/editors/image.theme.css
@@ -51,9 +51,9 @@
 }
 
 @keyframes quickedit-image-spin {
-  0% {transform: rotate(0deg);}
-  50% {transform: rotate(180deg);}
-  100% {transform: rotate(360deg);}
+  0% { transform: rotate(0deg); }
+  50% { transform: rotate(180deg); }
+  100% { transform: rotate(360deg); }
 }
 
 .quickedit-image-text {
diff --git a/core/modules/outside_in/css/off-canvas.css b/core/modules/outside_in/css/off-canvas.css
index 05ab539..b5aa0c5 100644
--- a/core/modules/outside_in/css/off-canvas.css
+++ b/core/modules/outside_in/css/off-canvas.css
@@ -6,18 +6,18 @@
  */
 /* Position the off-canvas dialog container outside the right of the viewport. */
 .ui-dialog-off-canvas {
-    box-sizing: border-box;
-    height: 100%;
-    overflow: visible;
+  box-sizing: border-box;
+  height: 100%;
+  overflow: visible;
 }
 
 /* Wrap the form that's inside the off-canvas dialog. */
 .ui-dialog-off-canvas .ui-dialog-content {
-    padding: 0 20px;
-    /* Prevent horizontal scrollbar. */
-    overflow-x: hidden;
-    overflow-y: auto;
+  padding: 0 20px;
+  /* Prevent horizontal scrollbar. */
+  overflow-x: hidden;
+  overflow-y: auto;
 }
 [dir="rtl"] .ui-dialog-off-canvas .ui-dialog-content {
-    text-align: right;
+  text-align: right;
 }
diff --git a/core/modules/outside_in/css/off-canvas.motion.css b/core/modules/outside_in/css/off-canvas.motion.css
index a6217ee..e395fbb 100644
--- a/core/modules/outside_in/css/off-canvas.motion.css
+++ b/core/modules/outside_in/css/off-canvas.motion.css
@@ -12,17 +12,17 @@
 
 /* Transition the off-canvas dialog container, with 2s delay to match main canvas speed. */
 .ui-dialog-off-canvas .ui-dialog-content {
-    -webkit-transition: all .7s ease 2s;
-    -moz-transition: all .7s ease 2s;
-    transition: all .7s ease 2s;
+  -webkit-transition: all .7s ease 2s;
+  -moz-transition: all .7s ease 2s;
+  transition: all .7s ease 2s;
 }
 
 @media (max-width: 700px) {
-    .ui-dialog-off-canvas .ui-dialog-content {
-        -webkit-transition: all .7s ease;
-        -moz-transition: all .7s ease;
-        transition: all .7s ease;
-    }
+  .ui-dialog-off-canvas .ui-dialog-content {
+    -webkit-transition: all .7s ease;
+    -moz-transition: all .7s ease;
+    transition: all .7s ease;
+  }
 }
 
 .dialog-off-canvas__main-canvas {
diff --git a/core/modules/outside_in/css/outside_in.motion.css b/core/modules/outside_in/css/outside_in.motion.css
index 3c86aca..5fae723 100644
--- a/core/modules/outside_in/css/outside_in.motion.css
+++ b/core/modules/outside_in/css/outside_in.motion.css
@@ -10,7 +10,6 @@
  *   file: https://www.drupal.org/node/2784443.
  */
 
-
 /* Transition the edit icon in the toolbar. */
 #toolbar-bar.button.toolbar-icon.toolbar-icon.toolbar-icon-edit:before {
   -webkit-transition: all .7s ease;
@@ -41,4 +40,5 @@
   -webkit-transition: all .7s ease;
   -moz-transition: all .7s ease;
   transition: all .7s ease;
-}*/
+}
+*/
diff --git a/core/modules/outside_in/css/outside_in.tabledrag.css b/core/modules/outside_in/css/outside_in.tabledrag.css
index e9d825f..28ebead 100644
--- a/core/modules/outside_in/css/outside_in.tabledrag.css
+++ b/core/modules/outside_in/css/outside_in.tabledrag.css
@@ -5,7 +5,6 @@
  * @see tabledrag.js
  */
 
-
 /* Because base font sizes will vary widely across themes, to maintain consistency outside-in uses only pixels. */
 
 .ui-dialog-outside-in body.drag {
diff --git a/core/modules/outside_in/css/outside_in.theme.css b/core/modules/outside_in/css/outside_in.theme.css
index 011d198..0db7a3c 100644
--- a/core/modules/outside_in/css/outside_in.theme.css
+++ b/core/modules/outside_in/css/outside_in.theme.css
@@ -97,7 +97,7 @@
 .ui-dialog-outside-in details,
 .ui-dialog-outside-in .form-item {
   color: #ddd;
-  font-family: "Lucida Grande", 'Lucida Sans Unicode','liberation sans', sans-serif;
+  font-family: "Lucida Grande", 'Lucida Sans Unicode', 'liberation sans', sans-serif;
   font-size: 14px;
   font-weight: normal;
   background-color: transparent;
@@ -106,7 +106,7 @@
 .ui-dialog-outside-in a,
 .ui-dialog-outside-in .link {
   border-bottom: none;
-  font-family: "Lucida Grande", 'Lucida Sans Unicode','liberation sans', sans-serif;
+  font-family: "Lucida Grande", 'Lucida Sans Unicode', 'liberation sans', sans-serif;
   font-size: 14px;
   font-weight: normal;
   color: #85bef4;
@@ -235,7 +235,6 @@
   background: #2b8bd8;
 }
 
-
 /*
  * Visual styling for dropbutton in the Settings Tray module's off canvas tray.
  * @todo Move to its own component:
diff --git a/core/modules/outside_in/css/outside_in.toolbar.css b/core/modules/outside_in/css/outside_in.toolbar.css
index 3f7e044..a199841 100644
--- a/core/modules/outside_in/css/outside_in.toolbar.css
+++ b/core/modules/outside_in/css/outside_in.toolbar.css
@@ -62,9 +62,9 @@ button.toolbar-icon.toolbar-icon-edit.toolbar-item:before:focus {
 }
 
 #toolbar-bar.js-outside-in-edit-mode button.toolbar-icon.toolbar-icon-edit.toolbar-item.is-active {
- background-image: none;
- color: #fff;
+  background-image: none;
+  color: #fff;
 }
 #toolbar-bar.js-outside-in-edit-mode button.toolbar-icon.toolbar-icon-edit.toolbar-item.is-active:hover {
- background-image: linear-gradient(to bottom, #0094f0, #0e69be);
+  background-image: linear-gradient(to bottom, #0094f0, #0e69be);
 }
diff --git a/core/modules/quickedit/css/quickedit.theme.css b/core/modules/quickedit/css/quickedit.theme.css
index 399db7a..120573a 100644
--- a/core/modules/quickedit/css/quickedit.theme.css
+++ b/core/modules/quickedit/css/quickedit.theme.css
@@ -99,7 +99,7 @@
  * Toolbars.
  */
 .quickedit-toolbar-container {
-  font-family: 'Source Sans Pro','Lucida Grande', sans-serif;
+  font-family: 'Source Sans Pro', 'Lucida Grande', sans-serif;
   padding-bottom: 7px;
   padding-top: 7px;
   -webkit-transition: all 1s;
@@ -174,9 +174,9 @@
   padding: 0.1667em 0.2em;
 }
 
- /**
-  * Info toolgroup.
-  */
+/**
+ * Info toolgroup.
+ */
 .quickedit-toolbar-fullwidth {
   width: 100%;
 }
diff --git a/core/modules/system/css/system.admin.css b/core/modules/system/css/system.admin.css
index 913ce57..be739ac 100644
--- a/core/modules/system/css/system.admin.css
+++ b/core/modules/system/css/system.admin.css
@@ -211,7 +211,7 @@ small .admin-link:after {
   background-color: transparent;
 }
 [dir="rtl"] .system-status-report__status-title {
-    padding: 10px 40px 10px 6px;
+  padding: 10px 40px 10px 6px;
 }
 .system-status-report__status-icon:before {
   content: "";
@@ -223,7 +223,7 @@ small .admin-link:after {
   left: 12px; /* LTR */
   top: 12px;
 }
-[dir="rtl"] .system-status-report__status-icon:before  {
+[dir="rtl"] .system-status-report__status-icon:before {
   left: auto;
   right: 12px;
 }
diff --git a/core/modules/system/tests/modules/layout_test/css/layout-test-2col.css b/core/modules/system/tests/modules/layout_test/css/layout-test-2col.css
index d5c05b9..ca7e876 100644
--- a/core/modules/system/tests/modules/layout_test/css/layout-test-2col.css
+++ b/core/modules/system/tests/modules/layout_test/css/layout-test-2col.css
@@ -1,4 +1,4 @@
-
+/* stylelint-disable plugin/no-browser-hacks */
 .layout-example-2col .region-left {
   float: left;
   width: 50%;
@@ -14,3 +14,4 @@
 * html .layout-example-2col .region-right {
   width: 49.9%;
 }
+/* stylelint-disable */
diff --git a/core/modules/toolbar/css/toolbar.icons.theme.css b/core/modules/toolbar/css/toolbar.icons.theme.css
index c52f868..54248a2 100644
--- a/core/modules/toolbar/css/toolbar.icons.theme.css
+++ b/core/modules/toolbar/css/toolbar.icons.theme.css
@@ -219,7 +219,6 @@
   background-color: #f5f5f5;
 }
 
-
 /**
  * Handle.
  */
@@ -280,8 +279,7 @@
   background-image: url(../../../misc/icons/bebebe/push-left.svg); /* LTR */
 }
 .toolbar .toolbar-toggle-orientation [value="vertical"]:hover:before,
-.toolbar .toolbar-toggle-orientation [value="vertical"]:focus:before
- {
+.toolbar .toolbar-toggle-orientation [value="vertical"]:focus:before {
   background-image: url(../../../misc/icons/787878/push-left.svg); /* LTR */
 }
 [dir="rtl"] .toolbar .toolbar-toggle-orientation [value="vertical"]:before {
diff --git a/core/modules/toolbar/css/toolbar.module.css b/core/modules/toolbar/css/toolbar.module.css
index 69eb7c2..324d806 100644
--- a/core/modules/toolbar/css/toolbar.module.css
+++ b/core/modules/toolbar/css/toolbar.module.css
@@ -111,7 +111,7 @@ body.toolbar-tray-open.toolbar-fixed.toolbar-vertical .toolbar-oriented {
 /* This min-width media query is meant to provide basic horizontal layout to
  * the main menu tabs when JavaScript is disabled on user agents that understand
  * media queries. */
-@media (min-width:16.5em) {
+@media (min-width: 16.5em) {
   .toolbar .toolbar-bar .toolbar-tab,
   .toolbar .toolbar-tray-horizontal li {
     float: left; /* LTR */
@@ -171,7 +171,7 @@ body.toolbar-tray-open.toolbar-fixed.toolbar-vertical .toolbar-oriented {
   right: 0;
 }
 /* Layer the links just above the toolbar-tray. */
-.toolbar .toolbar-bar .toolbar-tab > .toolbar-icon{
+.toolbar .toolbar-bar .toolbar-tab > .toolbar-icon {
   position: relative;
   z-index: 502;
 }
diff --git a/core/modules/toolbar/css/toolbar.theme.css b/core/modules/toolbar/css/toolbar.theme.css
index 981ee00..0b3afc9 100644
--- a/core/modules/toolbar/css/toolbar.theme.css
+++ b/core/modules/toolbar/css/toolbar.theme.css
@@ -20,7 +20,8 @@
   line-height: 1em;
   text-decoration: none;
 }
-.toolbar .toolbar-item:hover, .toolbar .toolbar-item:focus {
+.toolbar .toolbar-item:hover,
+.toolbar .toolbar-item:focus {
   text-decoration: underline;
 }
 
@@ -93,8 +94,7 @@
 .toolbar-tray a:hover,
 .toolbar-tray a:active,
 .toolbar-tray a:focus,
-.toolbar-tray a.is-active
- {
+.toolbar-tray a.is-active {
   color: #000;
   text-decoration: underline;
 }
@@ -105,7 +105,7 @@
   border-left: 1px solid #dddddd; /* LTR */
 }
 [dir="rtl"] .toolbar .toolbar-tray-horizontal .menu-item + .menu-item {
-  border-left: 0 none ;
+  border-left: 0 none;
   border-right: 1px solid #dddddd;
 }
 .toolbar .toolbar-tray-horizontal .menu-item:last-child {
diff --git a/core/modules/views_ui/css/views_ui.admin.css b/core/modules/views_ui/css/views_ui.admin.css
index e932af1..3d1db05 100644
--- a/core/modules/views_ui/css/views_ui.admin.css
+++ b/core/modules/views_ui/css/views_ui.admin.css
@@ -147,7 +147,7 @@
   margin-bottom: 2em;
 }
 
-@media screen and (min-width:45em) { /* 720px */
+@media screen and (min-width: 45em) { /* 720px */
   .views-display-columns > * {
     float: left; /* LTR */
     margin-left: 2%; /* LTR */
diff --git a/core/modules/views_ui/css/views_ui.admin.theme.css b/core/modules/views_ui/css/views_ui.admin.theme.css
index 460e75e..30616f0 100644
--- a/core/modules/views_ui/css/views_ui.admin.theme.css
+++ b/core/modules/views_ui/css/views_ui.admin.theme.css
@@ -158,7 +158,7 @@ details.box-padding {
 
 /* Hide 'remove' checkboxes. */
 .views-remove-checkbox {
-    display: none;
+  display: none;
 }
 
 /* sizes the labels of checkboxes and radio button to the height of the text */
@@ -345,7 +345,7 @@ td.group-title {
   padding: 0;
   width: auto;
 }
-.views-displays .tabs li.add ul.action-list li{
+.views-displays .tabs li.add ul.action-list li {
   margin: 0;
 }
 .views-displays .tabs.secondary li {
@@ -402,7 +402,7 @@ td.group-title {
   color: #0074bd;
   background-color: #f1f1f1;
 }
-.views-displays .tabs .action-list  li {
+.views-displays .tabs .action-list li {
   background-color: #f1f1f1;
   border-color: #cbcbcb;
   border-style: solid;
@@ -412,10 +412,10 @@ td.group-title {
 .views-displays .tabs .action-list li:first-child {
   border-width: 1px 1px 0;
 }
-.views-displays .action-list  li:last-child {
+.views-displays .action-list li:last-child {
   border-width: 0 1px 1px;
 }
-.views-displays .tabs .action-list  li:last-child {
+.views-displays .tabs .action-list li:last-child {
   border-width: 0 1px 1px;
 }
 .views-displays .tabs .action-list input.form-submit {
@@ -483,7 +483,7 @@ td.group-title {
 .view-preview-form .form-actions {
   vertical-align: top;
 }
-@media screen and (min-width:45em) { /* 720px */
+@media screen and (min-width: 45em) { /* 720px */
   .view-preview-form .form-type-textfield .description {
     white-space: nowrap;
   }
diff --git a/core/package.json b/core/package.json
index b168cb3..a8be250 100644
--- a/core/package.json
+++ b/core/package.json
@@ -6,14 +6,20 @@
   "scripts": {
     "build:js": "node ./scripts/js/babel-es6-build.js",
     "watch:js": "node ./scripts/js/babel-es6-watch.js",
-    "lint:js": "eslint . || exit 0"
+    "lint:js": "eslint . || exit 0",
+    "lint:css": "stylelint \"**/*.css\" || exit 0",
+    "lint:css-checkstyle": "stylelint \"**/*.css\" --custom-formatter ./node_modules/stylelint-checkstyle-formatter/index.js || exit 0"
   },
   "devDependencies": {
     "babel-core": "6.17.0",
     "babel-preset-es2015": "6.16.0",
     "chokidar": "1.6.0",
     "eslint": "3.8.1",
-    "glob": "^7.1.1"
+    "glob": "^7.1.1",
+    "stylelint": "^7.10.1",
+    "stylelint-config-standard": "^16.0.0",
+    "stylelint-checkstyle-formatter": "^0.1.0",
+    "stylelint-no-browser-hacks": "^1.0.2"
   },
   "babel": {
     "presets": [
diff --git a/core/themes/bartik/color/preview.css b/core/themes/bartik/color/preview.css
index ac561d3..48c124e 100644
--- a/core/themes/bartik/color/preview.css
+++ b/core/themes/bartik/color/preview.css
@@ -78,7 +78,7 @@
 }
 [dir="rtl"] .color-preview-sidebar,
 [dir="rtl"] .color-preview-content {
-    float: right;
+  float: right;
 }
 .color-preview-sidebar {
   margin-left: 15px; /* LTR */
diff --git a/core/themes/bartik/css/base/elements.css b/core/themes/bartik/css/base/elements.css
index ac47566..645cefa 100644
--- a/core/themes/bartik/css/base/elements.css
+++ b/core/themes/bartik/css/base/elements.css
@@ -132,7 +132,8 @@ img {
   max-width: 100%;
   height: auto;
 }
-ul, ol {
+ul,
+ol {
   margin: 0;
   padding: 0 0 0.25em 1em; /* LTR */
 }
diff --git a/core/themes/bartik/css/components/comments.css b/core/themes/bartik/css/components/comments.css
index a80e049..5acf4d5 100644
--- a/core/themes/bartik/css/components/comments.css
+++ b/core/themes/bartik/css/components/comments.css
@@ -49,7 +49,6 @@
   font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
   font-size: 0.733em;
   line-height: 1.2;
-
 }
 .comment__permalink {
   font-size: 0.733em;
diff --git a/core/themes/bartik/css/components/form.css b/core/themes/bartik/css/components/form.css
index 3e46920..5ff46e4 100644
--- a/core/themes/bartik/css/components/form.css
+++ b/core/themes/bartik/css/components/form.css
@@ -316,7 +316,9 @@ input.form-submit:focus {
     -moz-box-sizing: border-box;
   }
 
-  .js .dropbutton .dropbutton-action > input, .js .dropbutton .dropbutton-action > a, .js .dropbutton .dropbutton-action > button {
+  .js .dropbutton .dropbutton-action > input,
+  .js .dropbutton .dropbutton-action > a,
+  .js .dropbutton .dropbutton-action > button {
     text-align: center;
     padding-left: 3em;
   }
diff --git a/core/themes/bartik/css/components/header.css b/core/themes/bartik/css/components/header.css
index 40ea0f0..52ab1c6 100644
--- a/core/themes/bartik/css/components/header.css
+++ b/core/themes/bartik/css/components/header.css
@@ -21,7 +21,7 @@
   }
   .region-header .site-branding {
     float: left; /* LTR */
-   /* margin-bottom: 1.857em;*/
+    /* margin-bottom: 1.857em; */
   }
   [dir="rtl"] .region-header .site-branding {
     float: right;
diff --git a/core/themes/bartik/css/maintenance-page.css b/core/themes/bartik/css/maintenance-page.css
index 1196a22..eb1a3d0 100644
--- a/core/themes/bartik/css/maintenance-page.css
+++ b/core/themes/bartik/css/maintenance-page.css
@@ -49,7 +49,7 @@ body.maintenance-page {
 .maintenance-page .site-branding-text a:focus {
   color: #777;
 }
-.maintenance-page  .page-title {
+.maintenance-page .page-title {
   line-height: 1em;
   margin-top: 0;
 }
diff --git a/core/themes/classy/css/components/field.css b/core/themes/classy/css/components/field.css
index 0ef4c2d..daa8fb5 100644
--- a/core/themes/classy/css/components/field.css
+++ b/core/themes/classy/css/components/field.css
@@ -8,7 +8,7 @@
 }
 .field--label-inline .field__label,
 .field--label-inline .field__items {
-  float: left; /*LTR*/
+  float: left; /* LTR */
 }
 .field--label-inline .field__label,
 .field--label-inline > .field__item,
diff --git a/core/themes/classy/css/components/file.css b/core/themes/classy/css/components/file.css
index 5e16b4f..8bb3124 100644
--- a/core/themes/classy/css/components/file.css
+++ b/core/themes/classy/css/components/file.css
@@ -3,7 +3,7 @@
  * Default style for file module.
  */
 
-/* File icons.*/
+/* File icons. */
 
 .file {
   padding-left: 20px; /* LTR */
diff --git a/core/themes/classy/css/components/form.css b/core/themes/classy/css/components/form.css
index 15b8ec2..97b94fe 100644
--- a/core/themes/classy/css/components/form.css
+++ b/core/themes/classy/css/components/form.css
@@ -8,13 +8,13 @@ form .field-multiple-table {
 }
 form .field-multiple-table .field-multiple-drag {
   width: 30px;
-  padding-right: 0; /*LTR*/
+  padding-right: 0; /* LTR */
 }
 [dir="rtl"] form .field-multiple-table .field-multiple-drag {
   padding-left: 0;
 }
 form .field-multiple-table .field-multiple-drag .tabledrag-handle {
-  padding-right: .5em; /*LTR*/
+  padding-right: .5em; /* LTR */
 }
 [dir="rtl"] form .field-multiple-table .field-multiple-drag .tabledrag-handle {
   padding-right: 0;
@@ -64,8 +64,8 @@ label.option {
 }
 [dir="rtl"] .form-type-radio .description,
 [dir="rtl"] .form-type-checkbox .description {
-   margin-left: 0;
-   margin-right: 2.4em;
+  margin-left: 0;
+  margin-right: 2.4em;
 }
 .marker {
   color: #e00;
diff --git a/core/themes/classy/css/components/progress.css b/core/themes/classy/css/components/progress.css
index 1fb80a6..60bc123 100644
--- a/core/themes/classy/css/components/progress.css
+++ b/core/themes/classy/css/components/progress.css
@@ -17,27 +17,14 @@
   border: 1px #07629a solid;
   background: #057ec9;
   background-image:
-    -webkit-linear-gradient( top, rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.15) ),
-    -webkit-linear-gradient( left top,
-      #0094f0 0%,
-      #0094f0 25%,
-      #007ecc 25%,
-      #007ecc 50%,
-      #0094f0 50%,
-      #0094f0 75%,
-      #0094f0 100% );
+    -webkit-linear-gradient(top, rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.15)),
+    -webkit-linear-gradient(left top, #0094f0 0%, #0094f0 25%, #007ecc 25%, #007ecc 50%, #0094f0 50%, #0094f0 75%, #0094f0 100%);
   background-image:
-    -webkit-linear-gradient(top, rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.15)), -webkit-linear-gradient(left top, #0094f0 0%, #0094f0 25%, #007ecc 25%, #007ecc 50%, #0094f0 50%, #0094f0 75%, #0094f0 100%);
+    -webkit-linear-gradient(top, rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.15)),
+    -webkit-linear-gradient(left top, #0094f0 0%, #0094f0 25%, #007ecc 25%, #007ecc 50%, #0094f0 50%, #0094f0 75%, #0094f0 100%);
   background-image:
-    linear-gradient( to bottom, rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.15) ),
-    linear-gradient( to right bottom,
-      #0094f0 0%,
-      #0094f0 25%,
-      #007ecc 25%,
-      #007ecc 50%,
-      #0094f0 50%,
-      #0094f0 75%,
-      #0094f0 100% );
+    linear-gradient(to bottom, rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.15)),
+    linear-gradient(to right bottom, #0094f0 0%, #0094f0 25%, #007ecc 25%, #007ecc 50%, #0094f0 50%, #0094f0 75%, #0094f0 100%);
   background-size: 40px 40px;
   margin-top: -1px;
   margin-left: -1px; /* LTR */
@@ -61,11 +48,14 @@
  * Progress bar animations.
  */
 @-webkit-keyframes animate-stripes {
-  0% {background-position: 0 0, 0 0;} 100% {background-position: 0 0, -80px 0;}
+  0% { background-position: 0 0, 0 0; }
+  100% { background-position: 0 0, -80px 0; }
 }
 @-ms-keyframes animate-stripes {
-  0% {background-position: 0 0, 0 0;} 100% {background-position: 0 0, -80px 0;}
+  0% { background-position: 0 0, 0 0; }
+  100% { background-position: 0 0, -80px 0; }
 }
 @keyframes animate-stripes {
-  0% {background-position: 0 0, 0 0;} 100% {background-position: 0 0, -80px 0;}
+  0% { background-position: 0 0, 0 0; }
+  100% { background-position: 0 0, -80px 0; }
 }
diff --git a/core/themes/seven/css/base/print.css b/core/themes/seven/css/base/print.css
index 653e511..c432ccb 100644
--- a/core/themes/seven/css/base/print.css
+++ b/core/themes/seven/css/base/print.css
@@ -42,7 +42,8 @@
     color: #000;
     text-decoration: underline;
   }
-  .button, .button--primary {
+  .button,
+  .button--primary {
     background: none !important;
   }
   .messages {
@@ -70,7 +71,17 @@
     background: none;
     border-radius: 4px;
   }
-  input.form-autocomplete, input.form-text, input.form-tel, input.form-email, input.form-url, input.form-search, input.form-number, input.form-color, input.form-file, textarea.form-textarea, select.form-select {
+  input.form-autocomplete,
+  input.form-text,
+  input.form-tel,
+  input.form-email,
+  input.form-url,
+  input.form-search,
+  input.form-number,
+  input.form-color,
+  input.form-file,
+  textarea.form-textarea,
+  select.form-select {
     border-width: 1px;
   }
 }
diff --git a/core/themes/seven/css/components/dialog.css b/core/themes/seven/css/components/dialog.css
index 99aaa53..7b2ea3b 100644
--- a/core/themes/seven/css/components/dialog.css
+++ b/core/themes/seven/css/components/dialog.css
@@ -60,7 +60,6 @@
 }
 .ui-dialog .ui-widget-content.ui-dialog-buttonpane {
   background: #f5f5f2;
-  /*border-top: 1px solid #bfbfbf;*/
   margin: 0;
   padding: 15px 20px;
   border-bottom-left-radius: 5px;
diff --git a/core/themes/seven/css/components/dropbutton.component.css b/core/themes/seven/css/components/dropbutton.component.css
index 229f1bd..deb4458 100644
--- a/core/themes/seven/css/components/dropbutton.component.css
+++ b/core/themes/seven/css/components/dropbutton.component.css
@@ -169,7 +169,7 @@
 .dropbutton-single .dropbutton-action a {
   padding: 4px 1.5em;
   border: 1px solid #a6a6a6;
-  border-radius: 20em!important;
+  border-radius: 20em !important;
   background-color: #f2f1eb;
   background-image: -webkit-linear-gradient(top, #f6f6f3, #e7e7df);
   background-image: linear-gradient(to bottom, #f6f6f3, #e7e7df);
@@ -180,7 +180,7 @@
   -webkit-transition: all 0.1s;
   transition: all 0.1s;
   -webkit-font-smoothing: antialiased;
-  width: auto!important;
+  width: auto !important;
 }
 .dropbutton-single .dropbutton-action a:hover,
 .dropbutton-single .dropbutton-action a:focus {
diff --git a/core/themes/seven/css/components/entity-meta.css b/core/themes/seven/css/components/entity-meta.css
index 9877ec3..701e8dc 100644
--- a/core/themes/seven/css/components/entity-meta.css
+++ b/core/themes/seven/css/components/entity-meta.css
@@ -55,5 +55,5 @@
   text-shadow: 0 1px 0 white;
 }
 .entity-meta details .summary {
- display: none; /* Hide JS summaries. @todo Rethink summaries. */
+  display: none; /* Hide JS summaries. @todo Rethink summaries. */
 }
diff --git a/core/themes/seven/css/components/form.css b/core/themes/seven/css/components/form.css
index f3acc2c..0db30e8 100644
--- a/core/themes/seven/css/components/form.css
+++ b/core/themes/seven/css/components/form.css
@@ -127,7 +127,6 @@ label[for] {
   padding: 0.25em 0.666em 0;
 }
 
-
 /* Filter */
 ul.tips,
 div.description,
@@ -254,8 +253,9 @@ select {
   }
   select:focus,
   select:hover {
-    background-image: url(../../../../misc/icons/333333/caret-down.svg),
-    -webkit-linear-gradient(top, #fcfcfa, #e9e9dd);
+    background-image:
+      url(../../../../misc/icons/333333/caret-down.svg),
+      -webkit-linear-gradient(top, #fcfcfa, #e9e9dd);
     color: #1a1a1a;
   }
   select:hover {
diff --git a/core/themes/seven/css/components/messages.css b/core/themes/seven/css/components/messages.css
index c23a4d1..8b521cc 100644
--- a/core/themes/seven/css/components/messages.css
+++ b/core/themes/seven/css/components/messages.css
@@ -10,12 +10,18 @@
 .messages pre {
   margin: 0;
 }
-.messages h1, .messages .heading-a,
-.messages h2, .messages .heading-b,
-.messages h3, .messages .heading-c,
-.messages h4, .messages .heading-d,
-.messages h5, .messages .heading-e,
-.messages h6, .messages .heading-f {
+.messages h1,
+.messages .heading-a,
+.messages h2,
+.messages .heading-b,
+.messages h3,
+.messages .heading-c,
+.messages h4,
+.messages .heading-d,
+.messages h5,
+.messages .heading-e,
+.messages h6,
+.messages .heading-f {
   margin-top: 0;
 }
 
diff --git a/core/themes/seven/css/components/system-status-counter.css b/core/themes/seven/css/components/system-status-counter.css
index c3e0f30..8d71965 100644
--- a/core/themes/seven/css/components/system-status-counter.css
+++ b/core/themes/seven/css/components/system-status-counter.css
@@ -71,7 +71,7 @@
 
 @media screen and (min-width: 61em) {
   .system-status-counter__status-icon,
-  .system-status-counter  {
+  .system-status-counter {
     height: 65px;
   }
   .system-status-counter__status-icon {
diff --git a/core/themes/seven/css/components/system-status-report.css b/core/themes/seven/css/components/system-status-report.css
index bfcd75c..7869fbd 100644
--- a/core/themes/seven/css/components/system-status-report.css
+++ b/core/themes/seven/css/components/system-status-report.css
@@ -22,7 +22,7 @@
 .system-status-report__entry--warning {
   background-color: transparent;
 }
-  /* Account for native and poly-filled details element */
+/* Account for native and poly-filled details element */
 .system-status-report__status-title {
   position: relative;
   padding: 1em 1em 1em 3em; /* LTR */
diff --git a/core/themes/seven/css/components/tabs.css b/core/themes/seven/css/components/tabs.css
index 28401b4..5aab30b 100644
--- a/core/themes/seven/css/components/tabs.css
+++ b/core/themes/seven/css/components/tabs.css
@@ -1,7 +1,7 @@
 /**
  * Tabs.
  */
-.is-collapse-enabled  .tabs,
+.is-collapse-enabled .tabs,
 .is-horizontal .tabs {
   position: relative;
 }
@@ -107,7 +107,7 @@ li.tabs__tab a {
 }
 
 /* Only add the arrow if there's space */
-@media screen and (min-width:18.75em) { /* 300px */
+@media screen and (min-width: 18.75em) { /* 300px */
   .tabs.primary a {
     background: url(../../../../misc/icons/0074bd/chevron-right.svg) 99% center no-repeat;
   }
@@ -123,7 +123,7 @@ li.tabs__tab a {
 }
 
 /* JS dependent styling */
- .is-collapse-enabled .tabs__trigger {
+.is-collapse-enabled .tabs__trigger {
   box-sizing: content-box;
   display: block;
   position: absolute;
diff --git a/core/themes/seven/css/components/views-ui.css b/core/themes/seven/css/components/views-ui.css
index 6849781..d212dd0 100644
--- a/core/themes/seven/css/components/views-ui.css
+++ b/core/themes/seven/css/components/views-ui.css
@@ -74,7 +74,6 @@ details.fieldset-no-legend {
   margin-right: 1.5em;
 }
 
-
 .views-admin-dependent .form-item .form-item,
 .views-admin-dependent .form-type-checkboxes,
 .views-admin-dependent .form-type-radios,
@@ -169,7 +168,7 @@ details.fieldset-no-legend {
  */
 
 .views-displays .secondary {
- text-align: left; /* LTR */
+  text-align: left; /* LTR */
 }
 [dir="rtl"] .views-displays .secondary {
   text-align: right;
@@ -193,14 +192,14 @@ details.fieldset-no-legend {
   color: #008BCB;
 }
 
-.views-displays .secondary .action-list  li:first-child {
+.views-displays .secondary .action-list li:first-child {
   border-radius: 0 7px 0 0; /* LTR */
 }
-[dir="rtl"] .views-displays .secondary .action-list  li:first-child {
+[dir="rtl"] .views-displays .secondary .action-list li:first-child {
   border-radius: 7px 0 0 0;
 }
 
-.views-displays .secondary .action-list  li:last-child {
+.views-displays .secondary .action-list li:last-child {
   border-radius: 0 0 7px 7px;
 }
 
diff --git a/core/themes/seven/css/theme/install-page.css b/core/themes/seven/css/theme/install-page.css
index 350e1e6..ad43e4f 100644
--- a/core/themes/seven/css/theme/install-page.css
+++ b/core/themes/seven/css/theme/install-page.css
@@ -59,5 +59,4 @@
     width: auto;
     max-width: 100%;
   }
-
 }
diff --git a/core/themes/seven/css/theme/maintenance-page.css b/core/themes/seven/css/theme/maintenance-page.css
index f067a36..bea8321 100644
--- a/core/themes/seven/css/theme/maintenance-page.css
+++ b/core/themes/seven/css/theme/maintenance-page.css
@@ -135,7 +135,9 @@
     padding: 1em 0;
     vertical-align: middle;
   }
-  html, .install-page, .maintenance-page {
+  html,
+  .install-page,
+  .maintenance-page {
     margin: 0;
     width: 100%;
     height: 100%;
diff --git a/core/themes/stable/css/block/block.admin.css b/core/themes/stable/css/block/block.admin.css
index ed12038..08686e7 100644
--- a/core/themes/stable/css/block/block.admin.css
+++ b/core/themes/stable/css/block/block.admin.css
@@ -24,7 +24,7 @@ a.block-demo-backlink:visited {
   font-family: "Lucida Grande", Verdana, sans-serif;
   font-size: small;
   line-height: 20px;
-  left: 20px; /*LTR*/
+  left: 20px; /* LTR */
   padding: 5px 10px;
   position: fixed;
   z-index: 499;
diff --git a/core/themes/stable/css/ckeditor/ckeditor-iframe.css b/core/themes/stable/css/ckeditor/ckeditor-iframe.css
index 8996334..c34a683 100644
--- a/core/themes/stable/css/ckeditor/ckeditor-iframe.css
+++ b/core/themes/stable/css/ckeditor/ckeditor-iframe.css
@@ -16,7 +16,9 @@ body {
   }
 }
 
-ol, ul, dl {
+ol,
+ul,
+dl {
   /* Preserved spaces for list items with text direction other than the list.
    * (CKEditor issues #6249,#8049) */
   padding: 0 40px;
diff --git a/core/themes/stable/css/ckeditor/ckeditor.admin.css b/core/themes/stable/css/ckeditor/ckeditor.admin.css
index 8b771c7..cfbeae0 100644
--- a/core/themes/stable/css/ckeditor/ckeditor.admin.css
+++ b/core/themes/stable/css/ckeditor/ckeditor.admin.css
@@ -6,8 +6,6 @@
  * "moono".
  */
 
-
-
 .ckeditor-toolbar {
   border: 1px solid #b6b6b6;
   padding: 0.1667em 0.1667em 0.08em;
@@ -119,7 +117,7 @@
   margin: 3px 6px;
   padding: 3px;
 }
-.ckeditor-toolbar-configuration .fieldset-description{
+.ckeditor-toolbar-configuration .fieldset-description {
   margin-bottom: 1em;
 }
 .ckeditor-toolbar-disabled .ckeditor-toolbar-available,
diff --git a/core/themes/stable/css/core/dropbutton/dropbutton.css b/core/themes/stable/css/core/dropbutton/dropbutton.css
index 5990514..8b8709d 100644
--- a/core/themes/stable/css/core/dropbutton/dropbutton.css
+++ b/core/themes/stable/css/core/dropbutton/dropbutton.css
@@ -17,14 +17,14 @@
   position: relative;
 }
 
-@media screen and (max-width:600px) {
+@media screen and (max-width: 600px) {
   .js .dropbutton-wrapper {
     width: 100%;
   }
 }
 
 /* Splitbuttons */
-@media screen and (min-width:600px) {
+@media screen and (min-width: 600px) {
   .form-actions .dropbutton-wrapper {
     float: left; /* LTR */
   }
diff --git a/core/themes/stable/css/core/print.css b/core/themes/stable/css/core/print.css
index 6e69a3b..586d332 100644
--- a/core/themes/stable/css/core/print.css
+++ b/core/themes/stable/css/core/print.css
@@ -17,7 +17,7 @@ th {
 tr:nth-child(odd) {
   background-color: #ddd;
 }
-tr:nth-child(even){
+tr:nth-child(even) {
   background-color: #fff;
 }
 td {
diff --git a/core/themes/stable/css/core/vertical-tabs.css b/core/themes/stable/css/core/vertical-tabs.css
index ec5d3c1..fc83da5 100644
--- a/core/themes/stable/css/core/vertical-tabs.css
+++ b/core/themes/stable/css/core/vertical-tabs.css
@@ -8,8 +8,8 @@
   border: 1px solid #ccc;
 }
 [dir="rtl"] .vertical-tabs {
-   margin-left: 0;
-   margin-right: 15em;
+  margin-left: 0;
+  margin-right: 15em;
 }
 .vertical-tabs__menu {
   float: left; /* LTR */
diff --git a/core/themes/stable/css/file/file.admin.css b/core/themes/stable/css/file/file.admin.css
index 6a45644..38ad478 100644
--- a/core/themes/stable/css/file/file.admin.css
+++ b/core/themes/stable/css/file/file.admin.css
@@ -3,7 +3,7 @@
  * Admin stylesheet for file module.
  */
 
-/* File upload widget.*/
+/* File upload widget. */
 .form-managed-file .form-submit {
   margin: 0 0.5em;
 }
diff --git a/core/themes/stable/css/image/editors/image.theme.css b/core/themes/stable/css/image/editors/image.theme.css
index 5520758..f7a1b3a 100644
--- a/core/themes/stable/css/image/editors/image.theme.css
+++ b/core/themes/stable/css/image/editors/image.theme.css
@@ -51,9 +51,9 @@
 }
 
 @keyframes quickedit-image-spin {
-  0% {transform: rotate(0deg);}
-  50% {transform: rotate(180deg);}
-  100% {transform: rotate(360deg);}
+  0% { transform: rotate(0deg); }
+  50% { transform: rotate(180deg); }
+  100% { transform: rotate(360deg); }
 }
 
 .quickedit-image-text {
diff --git a/core/themes/stable/css/quickedit/quickedit.theme.css b/core/themes/stable/css/quickedit/quickedit.theme.css
index 399db7a..120573a 100644
--- a/core/themes/stable/css/quickedit/quickedit.theme.css
+++ b/core/themes/stable/css/quickedit/quickedit.theme.css
@@ -99,7 +99,7 @@
  * Toolbars.
  */
 .quickedit-toolbar-container {
-  font-family: 'Source Sans Pro','Lucida Grande', sans-serif;
+  font-family: 'Source Sans Pro', 'Lucida Grande', sans-serif;
   padding-bottom: 7px;
   padding-top: 7px;
   -webkit-transition: all 1s;
@@ -174,9 +174,9 @@
   padding: 0.1667em 0.2em;
 }
 
- /**
-  * Info toolgroup.
-  */
+/**
+ * Info toolgroup.
+ */
 .quickedit-toolbar-fullwidth {
   width: 100%;
 }
diff --git a/core/themes/stable/css/system/system.admin.css b/core/themes/stable/css/system/system.admin.css
index cd92b1a..6f5f62b 100644
--- a/core/themes/stable/css/system/system.admin.css
+++ b/core/themes/stable/css/system/system.admin.css
@@ -211,7 +211,7 @@ small .admin-link:after {
   background-color: transparent;
 }
 [dir="rtl"] .system-status-report__status-title {
-    padding: 10px 40px 10px 6px;
+  padding: 10px 40px 10px 6px;
 }
 .system-status-report__status-icon:before {
   content: "";
@@ -223,7 +223,7 @@ small .admin-link:after {
   left: 12px; /* LTR */
   top: 12px;
 }
-[dir="rtl"] .system-status-report__status-icon:before  {
+[dir="rtl"] .system-status-report__status-icon:before {
   left: auto;
   right: 12px;
 }
diff --git a/core/themes/stable/css/toolbar/toolbar.icons.theme.css b/core/themes/stable/css/toolbar/toolbar.icons.theme.css
index 54942d5..2a0614a 100644
--- a/core/themes/stable/css/toolbar/toolbar.icons.theme.css
+++ b/core/themes/stable/css/toolbar/toolbar.icons.theme.css
@@ -219,7 +219,6 @@
   background-color: #f5f5f5;
 }
 
-
 /**
  * Handle.
  */
@@ -280,8 +279,7 @@
   background-image: url(../../images/core/icons/bebebe/push-left.svg); /* LTR */
 }
 .toolbar .toolbar-toggle-orientation [value="vertical"]:hover:before,
-.toolbar .toolbar-toggle-orientation [value="vertical"]:focus:before
- {
+.toolbar .toolbar-toggle-orientation [value="vertical"]:focus:before {
   background-image: url(../../images/core/icons/787878/push-left.svg); /* LTR */
 }
 [dir="rtl"] .toolbar .toolbar-toggle-orientation [value="vertical"]:before {
diff --git a/core/themes/stable/css/toolbar/toolbar.module.css b/core/themes/stable/css/toolbar/toolbar.module.css
index 69eb7c2..324d806 100644
--- a/core/themes/stable/css/toolbar/toolbar.module.css
+++ b/core/themes/stable/css/toolbar/toolbar.module.css
@@ -111,7 +111,7 @@ body.toolbar-tray-open.toolbar-fixed.toolbar-vertical .toolbar-oriented {
 /* This min-width media query is meant to provide basic horizontal layout to
  * the main menu tabs when JavaScript is disabled on user agents that understand
  * media queries. */
-@media (min-width:16.5em) {
+@media (min-width: 16.5em) {
   .toolbar .toolbar-bar .toolbar-tab,
   .toolbar .toolbar-tray-horizontal li {
     float: left; /* LTR */
@@ -171,7 +171,7 @@ body.toolbar-tray-open.toolbar-fixed.toolbar-vertical .toolbar-oriented {
   right: 0;
 }
 /* Layer the links just above the toolbar-tray. */
-.toolbar .toolbar-bar .toolbar-tab > .toolbar-icon{
+.toolbar .toolbar-bar .toolbar-tab > .toolbar-icon {
   position: relative;
   z-index: 502;
 }
diff --git a/core/themes/stable/css/toolbar/toolbar.theme.css b/core/themes/stable/css/toolbar/toolbar.theme.css
index 981ee00..0b3afc9 100644
--- a/core/themes/stable/css/toolbar/toolbar.theme.css
+++ b/core/themes/stable/css/toolbar/toolbar.theme.css
@@ -20,7 +20,8 @@
   line-height: 1em;
   text-decoration: none;
 }
-.toolbar .toolbar-item:hover, .toolbar .toolbar-item:focus {
+.toolbar .toolbar-item:hover,
+.toolbar .toolbar-item:focus {
   text-decoration: underline;
 }
 
@@ -93,8 +94,7 @@
 .toolbar-tray a:hover,
 .toolbar-tray a:active,
 .toolbar-tray a:focus,
-.toolbar-tray a.is-active
- {
+.toolbar-tray a.is-active {
   color: #000;
   text-decoration: underline;
 }
@@ -105,7 +105,7 @@
   border-left: 1px solid #dddddd; /* LTR */
 }
 [dir="rtl"] .toolbar .toolbar-tray-horizontal .menu-item + .menu-item {
-  border-left: 0 none ;
+  border-left: 0 none;
   border-right: 1px solid #dddddd;
 }
 .toolbar .toolbar-tray-horizontal .menu-item:last-child {
diff --git a/core/themes/stable/css/views_ui/views_ui.admin.css b/core/themes/stable/css/views_ui/views_ui.admin.css
index e932af1..3d1db05 100644
--- a/core/themes/stable/css/views_ui/views_ui.admin.css
+++ b/core/themes/stable/css/views_ui/views_ui.admin.css
@@ -147,7 +147,7 @@
   margin-bottom: 2em;
 }
 
-@media screen and (min-width:45em) { /* 720px */
+@media screen and (min-width: 45em) { /* 720px */
   .views-display-columns > * {
     float: left; /* LTR */
     margin-left: 2%; /* LTR */
diff --git a/core/themes/stable/css/views_ui/views_ui.admin.theme.css b/core/themes/stable/css/views_ui/views_ui.admin.theme.css
index e4ac1e4..b843586 100644
--- a/core/themes/stable/css/views_ui/views_ui.admin.theme.css
+++ b/core/themes/stable/css/views_ui/views_ui.admin.theme.css
@@ -158,7 +158,7 @@ details.box-padding {
 
 /* Hide 'remove' checkboxes. */
 .views-remove-checkbox {
-    display: none;
+  display: none;
 }
 
 /* sizes the labels of checkboxes and radio button to the height of the text */
@@ -345,7 +345,7 @@ td.group-title {
   padding: 0;
   width: auto;
 }
-.views-displays .tabs li.add ul.action-list li{
+.views-displays .tabs li.add ul.action-list li {
   margin: 0;
 }
 .views-displays .tabs.secondary li {
@@ -402,7 +402,7 @@ td.group-title {
   color: #0074bd;
   background-color: #f1f1f1;
 }
-.views-displays .tabs .action-list  li {
+.views-displays .tabs .action-list li {
   background-color: #f1f1f1;
   border-color: #cbcbcb;
   border-style: solid;
@@ -412,10 +412,10 @@ td.group-title {
 .views-displays .tabs .action-list li:first-child {
   border-width: 1px 1px 0;
 }
-.views-displays .action-list  li:last-child {
+.views-displays .action-list li:last-child {
   border-width: 0 1px 1px;
 }
-.views-displays .tabs .action-list  li:last-child {
+.views-displays .tabs .action-list li:last-child {
   border-width: 0 1px 1px;
 }
 .views-displays .tabs .action-list input.form-submit {
@@ -483,7 +483,7 @@ td.group-title {
 .view-preview-form .form-actions {
   vertical-align: top;
 }
-@media screen and (min-width:45em) { /* 720px */
+@media screen and (min-width: 45em) { /* 720px */
   .view-preview-form .form-type-textfield .description {
     white-space: nowrap;
   }