Administration: Fix minor misalignments caused by the button-link CSS class.

After [40059] the CSS class `button-link` uses `text-align: left` by default.
This change now requires to limit as much as possible the use of `button-link`
to controls that should really look like links and to explicitly set
`text-align: center` in a few other cases.

Fixes #39983.


git-svn-id: https://develop.svn.wordpress.org/trunk@40358 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/css/media-views.css

@@ -183,19 +183,28 @@
 	right: 0;
 	width: 50px;
 	height: 50px;
+	margin: 0;
 	padding: 0;
+	border: 1px solid transparent;
+	background: none;
+	color: #666;
 	z-index: 1000;
+	cursor: pointer;
+	outline: none;
 	-webkit-transition: color .1s ease-in-out, background .1s ease-in-out;
 	transition: color .1s ease-in-out, background .1s ease-in-out;
 }
 
-.media-modal-close.button-link {
-	text-decoration: none;
+.media-modal-close:hover,
+.media-modal-close:active {
+	color: #00a0d2;
 }
 
-.media-modal-close:active {
-	-webkit-box-shadow: none;
-	box-shadow: none;
+.media-modal-close:focus {
+	color: #00a0d2;
+	border-color: #5b9dd9;
+	-webkit-box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
+	box-shadow: 0 0 3px rgba( 0, 115, 170, .8 );
 }
 
 .media-modal-close span.media-modal-icon {
@@ -209,15 +218,6 @@
 	vertical-align: middle;
 	-webkit-font-smoothing: antialiased;
 	-moz-osx-font-smoothing: grayscale;
-	color: #666;
-}
-
-.media-modal-close:hover .media-modal-icon:before {
-	color: #00a0d2;
-}
-
-.media-modal-close:active {
-	outline: 0;
 }
 
 .media-modal-content {

src/wp-includes/css/wp-auth-check.css

@@ -93,6 +93,7 @@
 	width: 22px;
 	color: #72777c;
 	text-decoration: none;
+	text-align: center;
 }
 
 #wp-auth-check-wrap .wp-auth-check-close:before {