Index: src/wp-content/themes/twentythirteen/css/editor-blocks.css
===================================================================
--- src/wp-content/themes/twentythirteen/css/editor-blocks.css	(revision 53486)
+++ src/wp-content/themes/twentythirteen/css/editor-blocks.css	(working copy)
@@ -319,18 +319,26 @@
 	width: 100%;
 }
 
+.block-editor-block-list__block.wp-block-table th,
 .wp-block-table th {
 	border: 0;
 	font-weight: bold;
 	text-transform: uppercase;
+	padding: 0.5em;
 }
 
+.block-editor-block-list__block.wp-block-table td,
 .editor-block-list__block .wp-block-table td {
 	border: 0;
 	border-top: 1px solid #ededed;
-	padding: 0;
+	padding: 0.5em;
 }
 
+.wp-block-table th:focus,
+.wp-block-table td:focus {
+	box-shadow: inset 0 0 0 1px var(--wp-admin-theme-color);
+}
+
 /*--------------------------------------------------------------
 6.0 Blocks - Layout Elements
 --------------------------------------------------------------*/