use 'auto' initial property

assets/sass/_theme/sections/diplomas.sass

@@ -130,7 +130,7 @@ ul.diplomas
             > a
                 width: columns(6)
             button
-                min-width: unset
+                min-width: auto
         @include media-breakpoint-up(md)
             flex-direction: column
             gap: $spacing-3