diff --git a/prototype/UI/style.css b/prototype/UI/style.css
index cb9c42eeb..7bb788b2c 100644
--- a/prototype/UI/style.css
+++ b/prototype/UI/style.css
@@ -36,31 +36,31 @@ td {
 }
 
 .empty-cell {
-    background-color: #fafafa;
-    border-right-color: #eee;
+  background-color: #fafafa;
+  border-right-color: #eee;
 }
 
 .blob-code+.blob-num {
-    border-left-width: 1px;
+  border-left-width: 1px;
 }
 
 #before, #after {
-	width: 50%;
+  width: 50%;
 }
 #before {
-	float: left;
+  float: left;
 }
 #after {
-	float: right;
+  float: right;
 }
 body {
-	margin: 0;
-	padding: 0;
-	font-family: monospace;
 }
 .insert {
 	background-color: #eaffea;
 	outline: 1px solid #c1e9c1;
+  margin: 0;
+  padding: 0;
+  font-family: monospace;
 }
 .delete {
 	background-color: #ffecec;
@@ -77,21 +77,21 @@ body {
 }
 
 .diff div, .diff ul, .diff li, .diff dl, .diff dd, .diff span {
-	white-space: pre-wrap;
-	display: inline;
-	margin: 0;
-	padding: 0;
-	color: initial;
+  white-space: pre-wrap;
+  display: inline;
+  margin: 0;
+  padding: 0;
+  color: initial;
 }
 
 .diff dt {
-	display: none;
+  display: none;
 }
 
 /* syntax highlighting */
 .diff .category-regex,
 .diff .category-string {
-	color: #183691;
+  color: #183691;
 }
 
 .diff .category-false,
@@ -102,11 +102,11 @@ body {
 .diff .category-function_call>li>.category-identifier,
 .diff .category-function_call>li>.category-member_access>.category-identifier,
 .diff .category-member_access>:not(:first-child)>.category-identifier {
-	color: #0086b3;
+  color: #0086b3;
 }
 
 .diff .category-comment {
-	color: #969896;
+  color: #969896;
 }
 
 .diff [class^="category-"][class$="_op"],
@@ -121,12 +121,12 @@ body {
 .diff .category-function,
 .diff .category-assignment,
 .diff .category-var_assignment {
-	color: #a71d5d;
+  color: #a71d5d;
 }
 
 .diff .category-function>li:first-child>.category-identifier,
 .diff .category-new_expression>li>.category-function_call>li:first-child>.category-identifier,
 .diff .category-pair>li:first-child>.category-identifier,
 .diff .category-assignment>li:first-child>.category-member_access>:not(:first-child)>.category-identifier {
-	color: #795da3;
+  color: #795da3;
 }