Contents list style adjustments

- restore underline by default, in line with link styles across GOV.UK
- slightly increase spacing between links on mobile

app/assets/stylesheets/components/_contents-list.scss

@@ -10,40 +10,37 @@
   box-shadow: 0 20px 15px -10px $white;
 }
 
-// Remove underlines from lists of links
-// to improve legibility
 .app-c-contents-list__link {
-  text-decoration: none;
-
-  &:hover,
-  &:focus,
-  &:active {
-    text-decoration: underline;
-  }
-
   .app-c-contents-list__list-item--parent > & {
     font-weight: bold;
   }
 }
 
 .app-c-contents-list__list-item {
-  padding-top: $gutter / 4;
+  padding-top: $gutter-one-third;
   line-height: 1.3;
   list-style-type: none;
+
+  @include media(tablet) {
+    padding-top: $gutter-one-quarter;
+  }
 }
 
 .app-c-contents-list__list-item--dashed {
-  $contents-spacing: $gutter-half + 5;
+  $contents-spacing: $gutter-half + 10;
   margin-left: $contents-spacing;
   padding-right: $contents-spacing;
 
   &:before {
     content: "— ";
     margin-left: -$contents-spacing;
+    padding-right: 5px;
 
     .direction-rtl & {
       margin-left: 0;
       margin-right: -$contents-spacing;
+      padding-right: 0;
+      padding-left: 5px;
     }
   }