Merge pull request #5769 from hanakin/ticket/16248

[ticket/16248] swap logo for new svg version

phpBB/styles/prosilver/theme/colours.css

@@ -149,7 +149,7 @@ table.zebra-list tr:nth-child(even) td, ul.zebra-list li:nth-child(even) {
 }
 
 .site_logo {
-	background-image: url("./images/site_logo.gif");
+	background-image: url("./images/site_logo.svg");
 }
 
 /* Horizontal lists

phpBB/styles/prosilver/theme/common.css

@@ -176,6 +176,7 @@ a:hover	{ text-decoration: underline; }
 }
 
 .site_logo {
+	background-repeat: no-repeat;
 	display: inline-block;
 	width: 149px;
 	height: 52px;