Update editor layout. add delete line button

assets/style.css

@@ -379,10 +379,9 @@ main > h2 {
 
 /* === Edit form === */
 .edit-form { display: flex; flex-direction: column; }
-/* The sidebar is always empty while editing, so drop its grid track instead of
-   leaving a reserved 14rem gap on the right; wide mode then fills the viewport. */
-body.edit-mode .page-wrap { grid-template-columns: minmax(0, 1fr); }
-body.editor-wide .page-wrap { max-width: none; }
+/* The sidebar is always empty while editing, so the editor uses the full
+   viewport: drop the reserved 14rem sidebar track and the centered max-width. */
+body.edit-mode .page-wrap { grid-template-columns: minmax(0, 1fr); max-width: none; }
 /* CodeMirror mount. The .cm-editor visual treatment (border, bg, font, padding)
    lives in the CM theme (editor-build/entry.js), keyed off the same :root
    variables; this only sizes the container. */