diff --git a/.Jules/palette.md b/.Jules/palette.md
index 6e3411a..b0b031e 100644
--- a/.Jules/palette.md
+++ b/.Jules/palette.md
@@ -31,3 +31,6 @@
 ## 2026-06-09 - Empty State Feedback
 **Learning:** When a list or process finishes with zero results, an empty summary container gives no feedback, leaving the user wondering if it actually ran or failed silently.
 **Action:** Always provide a helpful empty state message explaining why no results might have occurred, using styles consistent with other hints to offer guidance without showing as an error.
+## 2026-10-26 - Semantic Grouping over ARIA Workarounds
+**Learning:** Prioritizing native semantic HTML (`<fieldset>` and `<legend>`) over generic `<div>` elements with ARIA attributes (`role="radiogroup"`, `aria-labelledby`) for form groups provides more robust accessibility out of the box, reduces markup bloat, and aligns with HTML standards.
+**Action:** Always use `<fieldset>` to group related form controls (like radio buttons or mode selectors) and `<legend>` for their label. If custom styling is needed, reset default browser styles (`border: none`, `margin: 0`, `padding: 0`) rather than resorting to non-semantic wrappers.
diff --git a/biome.json b/biome.json
index 85ee3ce..adb6282 100644
--- a/biome.json
+++ b/biome.json
@@ -1,5 +1,5 @@
 {
-  "$schema": "https://biomejs.dev/schemas/2.4.16/schema.json",
+  "$schema": "https://biomejs.dev/schemas/2.5.0/schema.json",
   "vcs": {
     "enabled": true,
     "clientKind": "git",
@@ -33,7 +33,7 @@
   "linter": {
     "enabled": true,
     "rules": {
-      "recommended": true,
+      "preset": "recommended",
       "suspicious": {
         "noExplicitAny": "off",
         "noImplicitAnyLet": "off"
diff --git a/popup.css b/popup.css
index 85153c2..c32113c 100644
--- a/popup.css
+++ b/popup.css
@@ -85,7 +85,21 @@ input[type="password"]:focus {
   margin-bottom: 8px;
 }
 
-.setting-row label {
+fieldset {
+  border: none;
+  margin: 0;
+  padding: 0;
+}
+
+legend {
+  display: block;
+  font-size: 12px;
+  color: #94a3b8;
+  margin-bottom: 6px;
+}
+
+.setting-row label,
+.setting-row legend {
   margin-bottom: 4px;
 }
 
diff --git a/popup.html b/popup.html
index e4c322c..6a91a70 100644
--- a/popup.html
+++ b/popup.html
@@ -13,20 +13,20 @@ <h1>Jules Task Archiver</h1>
 
     <section class="options">
       <h2>Options</h2>
-      <div class="setting-row">
-        <label id="opModeLabel">Operation</label>
-        <div class="segmented" id="opMode" role="group" aria-labelledby="opModeLabel">
+      <fieldset class="setting-row">
+        <legend id="opModeLabel">Operation</legend>
+        <div class="segmented" id="opMode">
           <button type="button" data-value="archive" class="active" aria-pressed="true">Archive Tasks</button>
           <button type="button" data-value="suggestions" aria-pressed="false">Start Suggestions</button>
         </div>
-      </div>
-      <div class="setting-row">
-        <label id="execModeLabel">Execution Mode</label>
-        <div class="radio-group" role="radiogroup" aria-labelledby="execModeLabel">
+      </fieldset>
+      <fieldset class="setting-row">
+        <legend id="execModeLabel">Execution Mode</legend>
+        <div class="radio-group">
           <label><input type="radio" name="mode" value="dry" checked /> Dry Run</label>
           <label><input type="radio" name="mode" value="run" /> Run</label>
         </div>
-      </div>
+      </fieldset>
       <div class="setting-row">
         <label class="checkbox">
           <input type="checkbox" id="force" aria-describedby="forceHint" />
@@ -34,13 +34,13 @@ <h2>Options</h2>
         </label>
         <span class="hint" id="forceHint" style="display: block; margin-left: 20px; margin-top: 2px;">Archive every task, ignoring state and matching open Pull Requests</span>
       </div>
-      <div class="setting-row">
-        <label id="scopeLabel">Scope</label>
-        <div class="radio-group" role="radiogroup" aria-labelledby="scopeLabel">
+      <fieldset class="setting-row">
+        <legend id="scopeLabel">Scope</legend>
+        <div class="radio-group">
           <label><input type="radio" name="scope" value="current" /> Current tab</label>
           <label><input type="radio" name="scope" value="all" checked /> All Jules tabs</label>
         </div>
-      </div>
+      </fieldset>
     </section>
 
     <section class="settings">
diff --git a/tests/popup.test.js b/tests/popup.test.js
index 3f3db03..6f7d210 100644
--- a/tests/popup.test.js
+++ b/tests/popup.test.js
@@ -435,11 +435,13 @@ describe('popup.html accessibility', () => {
     )
   })
 
-  it('should use explicit visible labels for radio groups via aria-labelledby', () => {
-    assert.ok(popupHtml.includes('id="execModeLabel"'), 'execModeLabel should exist')
-    assert.ok(popupHtml.includes('aria-labelledby="execModeLabel"'), 'mode radiogroup should use aria-labelledby')
-    assert.ok(popupHtml.includes('id="scopeLabel"'), 'scopeLabel should exist')
-    assert.ok(popupHtml.includes('aria-labelledby="scopeLabel"'), 'scope radiogroup should use aria-labelledby')
+  it('should use explicit semantic fieldsets and legends for grouped controls', () => {
+    assert.ok(popupHtml.includes('<fieldset class="setting-row">'), 'should use fieldset for grouped controls')
+    assert.ok(
+      popupHtml.includes('<legend id="execModeLabel">Execution Mode</legend>'),
+      'should use semantic legend for execution mode'
+    )
+    assert.ok(popupHtml.includes('<legend id="scopeLabel">Scope</legend>'), 'should use semantic legend for scope')
   })
 })