Fixing aria values and contrast for accessibility

lms/static/sass/course/modules/_calculator.scss

@@ -37,14 +37,20 @@ div.calc-main {
       background-color: $black;
       top: -36px;
     }
+
+    .utility-control-label {
+      background: $black;
+      color: $white;
+    }
   }
 
   div#calculator_wrapper {
-    background: $black;
     clear: both;
-    max-height: 90px;
     position: relative;
     top: -36px;
+    max-height: 90px;
+    background: $black;
+    color: $white;
 
     // UI: input help table
     .calculator-input-help-table {
@@ -62,6 +68,12 @@ div.calc-main {
       @include box-sizing(border-box);
       padding: lh();
 
+      label.sr {
+        // including the label here in case other .sr values are added
+        // we want to limit this 'white' only to the label
+        color: $white;
+      }
+
       button#calculator_button {
         background: #111;
         border: 1px solid $black;
@@ -82,6 +94,13 @@ div.calc-main {
         &:hover, &:focus {
           color: #333;
         }
+
+        span.sr {
+          // including the element here in case other .sr values are added
+          // we want to limit this 'white' only to the span
+          background: $black;
+          color: $white;
+        }
       }
 
       input#calculator_output {
@@ -125,19 +144,31 @@ div.calc-main {
           right: 0;
           top: 0;
 
+          #hint-instructions {
+            color: $white;
+          }
+
           #calculator_hint {
-            background: url("../images/info-icon.png") center center no-repeat;
-            height: 35px;
             @include hide-text;
-            width: 35px;
             display: block;
+            height: 35px;
+            width: 35px;
             border: none;
+            background: url("../images/info-icon.png") center center no-repeat;
+            color: $white;
 
             &:focus {
               outline: 5px auto #5b9dd9;
               box-shadow: none;
               border: none;
             }
+
+            span.sr {
+              // including the element here in case other .sr values are added
+              // we want to limit this 'white' only to the span
+              background: $black;
+              color: $white;
+            }
           }
 
           .help {

lms/templates/calculator/toggle_calculator.html

@@ -17,7 +17,7 @@ from django.core.urlresolvers import reverse
         <div class="help-wrapper">
           <p class="sr" id="hint-instructions">${_('Use the arrow keys to navigate the tips or use the tab key to return to the calculator')}</p>
 
-          <button id="calculator_hint" aria-haspopup="true" aria-expanded="false" aria-controls=“calculator_input_help” aria-describedby="hint-instructions"><span class="sr">${_("Hints")}</span></button>
+          <button id="calculator_hint" aria-haspopup="true" aria-expanded="false" aria-controls="calculator_input_help" aria-describedby="hint-instructions"><span class="sr">${_("Hints")}</span></button>
 
           <ul id="calculator_input_help" class="help" aria-hidden="true">
             <li class="hint-item" id="hint-moreinfo">