-body.about-php .tb-close-icon:before,
-body.plugin-install-php .tb-close-icon:before,
-body.import-php .tb-close-icon:before,
-body.plugins-php .tb-close-icon:before,
-body.update-core-php .tb-close-icon:before,
-body.index-php .tb-close-icon:before {
+body.about-php .tb-close-icon,
+body.plugin-install-php .tb-close-icon,
+body.import-php .tb-close-icon,
+body.plugins-php .tb-close-icon,
+body.update-core-php .tb-close-icon,
+body.index-php .tb-close-icon {
+ display: none;
+}
+
+body.about-php #TB_closeWindowButton:after,
+body.plugin-install-php #TB_closeWindowButton:after,
+body.import-php #TB_closeWindowButton:after,
+body.plugins-php #TB_closeWindowButton:after,
+body.update-core-php #TB_closeWindowButton:after,
+body.index-php #TB_closeWindowButton:after {