UX: fix category nav padding on small screens (#98)

This adjusts the active state of the dropdown by employing negative
margin to compensate for the padding

before:

![image](https://github.com/user-attachments/assets/e8c8a544-3527-4d6c-a513-0291a6a15ab5)


after:

![image](https://github.com/user-attachments/assets/4a53a0ee-a07d-43b0-9ab6-3542d86bbe8c)

scss/mobile-stuff.scss

@@ -35,10 +35,14 @@
           column-gap: var(--spacing-inline-s);
           row-gap: var(--spacing-block-xs);
           flex-basis: 100%;
+          li {
+            margin-right: 0;
+            margin-left: calc(
+              (var(--spacing-block-s) - 2px) * -1
+            ); // 2px is width of the outline
+          }
           .select-kit-header {
             background: var(--d-content-background);
-            padding-block: var(--spacing-block-s);
-            padding-inline: 0;
             border: 0;
           }
         }