Style updates for 2FA to handle mobile etc.

hypha/static_src/src/sass/apply/components/_two-factor.scss

@@ -11,6 +11,10 @@
         @extend %h3;
         font-weight: 700;
     }
+
+    .mb-3 {
+        margin-bottom: 1rem;
+    }
 }
 
 // 2FA token label font size
@@ -22,13 +26,18 @@ label[for='id_generator-token'] {
     display: none;
 }
 
+.bg-white {
+  background-color: $color--white;
+}
+
 // 2FA token field.
 // stylelint-disable property-no-vendor-prefix, selector-id-pattern, selector-max-id
 #id_generator-token {
     -moz-appearance: textfield;
-    border: 2px solid $color--dark-blue;
-    line-height: 1.35;
-    width: 20%;
+    border: 3px solid $color--dark-blue;
+    line-height: 1.5;
+    width: 8ch;
+    padding:  5px;
 
     &::-webkit-outer-spin-button,
     &::-webkit-inner-spin-button {