Fix: avoid extra space when there is no rule

edit/settings.css

@@ -26,7 +26,10 @@
   display: grid;
   grid-template-columns: minmax(min-content, 1fr) min-content;
   grid-gap: .3em;
-  margin: .3em 0;
+  margin: 0 0 .3em 0;
+}
+[data-length="0"] .rule-table {
+  margin: 0;
 }
 .radio-group .form-label {
   display: block;

edit/settings.js

@@ -69,6 +69,7 @@ function StyleSettings(editor) {
       if (!style[type]) {
         style[type] = [];
       }
+      container.dataset.length = style[type].length;
       style[type].forEach((rule, i) => {
         const input = document.createElement('input');
         input.value = rule;