Merge pull request #5105 from edx/talbs/os-ggg-a11y

LMS: Accessibility Tweaks 

common/lib/xmodule/xmodule/css/capa/display.scss

@@ -633,7 +633,7 @@ div.problem {
       // margin-top: 10px;
       display: inline-block;
       margin: 8px 0 0 $baseline/2;
-      color: #777;
+      color: #666;
       font-style: italic;
       -webkit-font-smoothing: antialiased;
     }

common/lib/xmodule/xmodule/css/combinedopenended/display.scss

@@ -828,7 +828,7 @@ section.open-ended-child {
     .submission_feedback {
       display: inline-block;
       margin: 8px 0 0 $baseline/2;
-      color: #777;
+      color: #666;
       font-style: italic;
       -webkit-font-smoothing: antialiased;
     }

lms/static/sass/_shame.scss

@@ -65,6 +65,9 @@
   &:hover, &:active, &:focus {
     background: $action-primary-focused-bg;
   }
+  &:focus {
+    box-shadow: 0 0 6px 0 $action-primary-active-focused-shadow;
+  }
 
   &.current, &.active {
     box-shadow: inset 0 2px 1px 1px $action-primary-active-shadow;
@@ -93,6 +96,9 @@
   &:hover, &:active, &:focus {
     background: $action-secondary-focused-bg;
   }
+  &:focus {
+    box-shadow: 0 0 6px 0 $action-primary-active-focused-shadow;
+  }
 
   &.current, &.active {
     box-shadow: inset 0 2px 1px 1px $action-secondary-active-shadow;