cleaning up LMS Sass variables a bit

lms/static/sass/base/_variables.scss

+$baseline: 20px;
+
 $gw-column: 80px;
 $gw-gutter: 20px;
-
 $fg-column: $gw-column;
 $fg-gutter: $gw-gutter;
 $fg-max-columns: 12;
@@ -8,25 +9,24 @@ $fg-max-width: 1400px;
 $fg-min-width: 810px;
 
 $sans-serif: 'Open Sans', $verdana;
-$body-font-family: $sans-serif;
-$serif: $georgia;
 $monospace: Monaco, 'Bitstream Vera Sans Mono', 'Lucida Console', monospace;
-
-$body-font-size: em(14);
-$body-line-height: golden-ratio(.875em, 1);
-$base-font-color: rgb(60,60,60);
-$lighter-base-font-color: rgb(100,100,100);
+$serif: $georgia;
 
 $blue: rgb(29,157,217);
 $pink: rgb(182,37,104);
 $yellow: rgb(255, 252, 221);
+$red: rgb(178, 6, 16);
 $error-red: rgb(253, 87, 87);
-$border-color: #C8C8C8;
-$sidebar-color: #f6f6f6;
-$outer-border-color: #aaa;
+$light-gray: rgb(221, 221, 221);
+$dark-gray: rgb(51, 51, 51);
+$border-color: rgb(200, 200, 200);
+$sidebar-color: rgb(246, 246, 246);
+$outer-border-color: rgb(170, 170, 170);
 
-// old variables
-$light-gray: #ddd;
-$dark-gray: #333;
+$base-font-color: rgb(60,60,60);
+$lighter-base-font-color: rgb(100,100,100);
 $text-color: $dark-gray;
 
+$body-font-family: $sans-serif;
+$body-font-size: em(14);
+$body-line-height: golden-ratio(.875em, 1);
\ No newline at end of file

lms/static/sass/multicourse/_testcenter-register.scss

-// ==========
-
-$baseline: 20px;
-$yellow: rgb(255, 235, 169);
-$red: rgb(178, 6, 16);
-
-// ==========
-
 .testcenter-register {
 	@include clearfix;
 	padding: 60px 0px 120px;