studio - minor design tweaks to alert/notification chrome

cms/static/sass/elements/_alerts.scss

@@ -12,7 +12,6 @@
 
 .wrapper-notification, .wrapper-alert, .prompt {
   background: $gray-d3;
-  border-top: 4px solid $gray-d4;
 
   .copy {
     color: $gray-l2;
@@ -242,7 +241,6 @@
   bottom: 0;
   z-index: 1000;
   width: 100%;
-  border-width: 2px;
   padding: $baseline ($baseline*2);
 
   &.wrapper-notification-warning {
@@ -452,7 +450,6 @@
   z-index: 100;
   overflow: hidden;
   width: 100%;
-  border-bottom: 2px solid $black;
   border-top: 1px solid $black;
   padding: $baseline ($baseline*2) ($baseline*1.5) ($baseline*2);
   background: $gray-d3;
@@ -521,7 +518,7 @@
     @include transition (color 0.5s ease-in-out);
     @include font-size(22);
     width: flex-grid(1, 12);
-    margin-right: flex-gutter();
+    margin: ($baseline/4) flex-gutter() 0 0;
     text-align: right;
   }