Changed urls for the portal-icons to be relative, which makes them work.

lms/static/sass/_course_about.scss

@@ -384,19 +384,19 @@
           width: 19px;
 
           &.start-icon {
-            @include background-image(url('/static/images/portal-icons/calendar-icon.png'));
+            @include background-image(url('../images/portal-icons/calendar-icon.png'));
           }
 
           &.final-icon {
-            @include background-image(url('/static/images/portal-icons/pencil-icon.png'));
+            @include background-image(url('../images/portal-icons/pencil-icon.png'));
           }
 
           &.length-icon {
-            @include background-image(url('/static/images/portal-icons/chart-icon.png'));
+            @include background-image(url('../images/portal-icons/chart-icon.png'));
           }
 
           &.number-icon {
-            @include background-image(url('/static/images/portal-icons/course-info-icon.png'));
+            @include background-image(url('../images/portal-icons/course-info-icon.png'));
           }
         }
 

lms/static/sass/shared/_header.scss

@@ -160,7 +160,7 @@ header.global {
 
         .avatar {
           //background: rgb(220,220,220);
-          @include background-image(url('/static/images/portal-icons/home-icon.png'));
+          @include background-image(url('../images/portal-icons/home-icon.png'));
           background-size: cover;
           //@include border-radius(3px);
           //border: 1px solid rgb(80,80,80);