Index: src/wp-content/themes/twentyfifteen/css/blocks.css
===================================================================
--- src/wp-content/themes/twentyfifteen/css/blocks.css	(revision 61418)
+++ src/wp-content/themes/twentyfifteen/css/blocks.css	(working copy)
@@ -590,6 +590,10 @@
 	background-color: #111;
 }
 
+.has-dark-gray-border-color {
+	border-color: #111;
+}
+
 .has-light-gray-color {
 	color: #f1f1f1;
 }
@@ -598,6 +602,10 @@
 	background-color: #f1f1f1;
 }
 
+.has-light-gray-border-color {
+	border-color: #f1f1f1;
+}
+
 .has-white-color {
 	color: #fff;
 }
@@ -606,6 +614,10 @@
 	background-color: #fff;
 }
 
+.has-white-border-color {
+	border-color: #fff;
+}
+
 .has-yellow-color {
 	color: #f4ca16;
 }
@@ -614,6 +626,10 @@
 	background-color: #f4ca16;
 }
 
+.has-yellow-border-color {
+	border-color: #f4ca16;
+}
+
 .has-dark-brown-color {
 	color: #352712;
 }
@@ -622,6 +638,10 @@
 	background-color: #352712;
 }
 
+.has-dark-brown-border-color {
+	border-color: #352712;
+}
+
 .has-medium-pink-color {
 	color: #e53b51;
 }
@@ -630,6 +650,10 @@
 	background-color: #e53b51;
 }
 
+.has-medium-pink-border-color {
+	border-color: #e53b51;
+}
+
 .has-light-pink-color {
 	color: #ffe5d1;
 }
@@ -638,6 +662,10 @@
 	background-color: #ffe5d1;
 }
 
+.has-light-pink-border-color {
+	border-color: #ffe5d1;
+}
+
 .has-dark-purple-color {
 	color: #2e2256;
 }
@@ -646,6 +674,10 @@
 	background-color: #2e2256;
 }
 
+.has-dark-purple-border-color {
+	border-color: #2e2256;
+}
+
 .has-purple-color {
 	color: #674970;
 }
@@ -654,6 +686,10 @@
 	background-color: #674970;
 }
 
+.has-purple-border-color {
+	border-color: #674970;
+}
+
 .has-blue-gray-color {
 	color: #22313f;
 }
@@ -662,6 +698,10 @@
 	background-color: #22313f;
 }
 
+.has-blue-gray-border-color {
+	border-color: #22313f;
+}
+
 .has-bright-blue-color {
 	color: #55c3dc;
 }
@@ -670,6 +710,10 @@
 	background-color: #55c3dc;
 }
 
+.has-bright-blue-border-color {
+	border-color: #55c3dc;
+}
+
 .has-light-blue-color {
 	color: #e9f2f9;
 }
@@ -678,6 +722,10 @@
 	background-color: #e9f2f9;
 }
 
+.has-light-blue-border-color {
+	border-color: #e9f2f9;
+}
+
 .has-dark-gray-gradient-background {
 	background-image: linear-gradient(90deg, rgba(17,17,17,1) 0%, rgba(42,42,42,1) 100%);
 }