Multiple UI improvements

webapp/sass/layout/_headers.scss

@@ -134,6 +134,10 @@
                 @include alpha-property(background, $black, .1);
             }
 
+            a {
+                text-decoration: none;
+            }
+
             .user__name {
                 color: $white;
             }

webapp/sass/layout/_navigation.scss

@@ -89,7 +89,7 @@
 
                 &.info-popover {
                     @include background-size(100% 100%);
-                    background: url('../images/info__icon.png');
+                    background-image: url('../images/info__icon.png');
                     cursor: pointer;
                     height: 19px;
                     position: relative;

webapp/sass/layout/_sidebar-left.scss

@@ -1,7 +1,6 @@
 @charset 'UTF-8';
 
 .sidebar--left {
-    background: #fafafa;
     border-right: $border-gray;
     height: 100%;
     left: 0;