diff --git a/public_html/style.css b/public_html/style.css
index f90930e..fedfb33 100644
--- a/public_html/style.css
+++ b/public_html/style.css
@@ -55,18 +55,34 @@ html, body {
 
 #toggle_sidebar_button.show_sidebar {
     background-image: url("images/table-icon.png");
-}
-
-#toggle_sidebar_button.show_sidebar:hover {
-    background-image: url("images/table-icon.png");
+    background-image: 
+        -webkit-image-set(
+            "images/table-icon.png" 1x,
+            "images/table-icon@2x.png" 2x,
+            "images/table-icon@3x.png" 3x
+        );
+    background-image: 
+        -image-set(
+            "images/table-icon.png" 1x,
+            "images/table-icon@2x.png" 2x,
+            "images/table-icon@3x.png" 3x
+        );
 }
 
 #toggle_sidebar_button.hide_sidebar {
     background-image: url("images/map-icon.png");
-}
-
-#toggle_sidebar_button.hide_sidebar:hover {
-    background-image: url("images/map-icon.png");
+    background-image: 
+        -webkit-image-set(
+            "images/map-icon.png" 1x,
+            "images/map-icon@2x.png" 2x,
+            "images/map-icon@3x.png" 3x
+        );
+    background-image: 
+        -image-set(
+            "images/map-icon.png" 1x,
+            "images/map-icon@2x.png" 2x,
+            "images/map-icon@3x.png" 3x
+        );
 }
 
 #expand_sidebar_control {
@@ -90,10 +106,18 @@ html, body {
 
 #expand_sidebar_button {
     background-image: url("images/table-icon.png");
-}
-
-#expand_sidebar_button:hover {
-    background-image: url("images/table-icon.png");
+    background-image: 
+        -webkit-image-set(
+            "images/table-icon.png" 1x,
+            "images/table-icon@2x.png" 2x,
+            "images/table-icon@3x.png" 3x
+        );
+    background-image: 
+        -image-set(
+            "images/table-icon.png" 1x,
+            "images/table-icon@2x.png" 2x,
+            "images/table-icon@3x.png" 3x
+        );
 }
 
 #sidebar_container {
@@ -118,10 +142,34 @@ html, body {
     background-color: transparent;
     border: none;
     background-image: url("images/column-adjust.png");
+    background-image: 
+        -webkit-image-set(
+            "images/column-adjust.png" 1x,
+            "images/column-adjust@2x.png" 2x,
+            "images/column-adjust@3x.png" 3x
+        );
+    background-image: 
+        -image-set(
+            "images/column-adjust.png" 1x,
+            "images/column-adjust@2x.png" 2x,
+            "images/column-adjust@3x.png" 3x
+        );
 }
 
 .ol-zoom-in {
     background-image: url("images/zoom-in.png");
+    background-image: 
+        -webkit-image-set(
+            "images/zoom-in.png" 1x,
+            "images/zoom-in@2x.png" 2x,
+            "images/zoom-in@3x.png" 3x
+        );
+    background-image: 
+        -image-set(
+            "images/zoom-in.png" 1x,
+            "images/zoom-in@2x.png" 2x,
+            "images/zoom-in@3x.png" 3x
+        );
     color:transparent !important;
     width: 19px !important;
     height: 19px !important;
@@ -131,6 +179,18 @@ html, body {
 
 .ol-zoom-out {
     background-image: url("images/zoom-out.png");
+    background-image: 
+        -webkit-image-set(
+            "images/zoom-out.png" 1x,
+            "images/zoom-out@2x.png" 2x,
+            "images/zoom-out@3x.png" 3x
+        );
+    background-image: 
+        -image-set(
+            "images/zoom-out.png" 1x,
+            "images/zoom-out@2x.png" 2x,
+            "images/zoom-out@3x.png" 3x
+        );
     color:transparent !important;
     width: 19px !important;
     height: 19px !important;
@@ -421,6 +481,7 @@ select.error, textarea.error, input.error {
     box-shadow: 4px 4px 10px #444444;
     cursor: pointer;
     z-index: 9999;
+    display: none;
 }
 
 .highlightedTitle {