[Glitch] Improve layout and spacing of number fields

Port cf7a092053 to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/components/number_fields/styles.module.scss

@@ -1,9 +1,11 @@
 .list {
+  --item-gap: var(--number-fields-gap, 24px);
+
   display: flex;
   flex-wrap: wrap;
   margin: 0;
   padding: 0;
-  gap: 4px 24px;
+  gap: 4px var(--item-gap);
   font-size: 13px;
   color: var(--color-text-secondary);
 }