diff --git a/index.html b/index.html
index 2d08b58..25ae3eb 100644
--- a/index.html
+++ b/index.html
@@ -472,15 +472,21 @@
             </div>
         </div>
 
-        <!-- Posimai API Key -->
+        <!-- 認証 / VOICEVOX -->
         <div style="margin-top:20px">
-            <div class="settings-group-label">Posimai API Key</div>
-            <p class="settings-field-label">
-                設定すると VPS 経由でずんだもん音声が使えます（未設定時はブラウザ音声）。
+            <div class="settings-group-label">アカウント</div>
+            <p class="settings-field-label" id="authStatusLabel">
+                ログインするとずんだもん音声・カスタムRSSが使えます。
             </p>
-            <input class="settings-text-input" id="apiKeyInput" type="password"
-                   placeholder="posimai_api_key" autocomplete="off">
-            <button class="settings-action-btn" id="apiKeySave">保存</button>
+            <div id="authLoggedIn" style="display:none">
+                <div id="authUserLine" style="font-size:13px;color:var(--accent);margin-bottom:8px"></div>
+                <button class="settings-action-btn" id="authLogoutBtn" style="background:transparent;border:1px solid var(--border);color:var(--text2)">ログアウト</button>
+            </div>
+            <div id="authLoggedOut">
+                <a class="settings-action-btn" id="authLoginBtn"
+                   style="display:inline-flex;align-items:center;gap:6px;text-decoration:none"
+                   href="#">ログインする</a>
+            </div>
         </div>
 
     </div>
@@ -562,6 +568,16 @@
 const FEED_API = 'https://posimai-feed.vercel.app/api/feed';
 const API_BASE = 'https://api.soar-enrich.com/brain/api';
 const TTS_API  = API_BASE + '/tts';
+
+// ── 認証ヘルパー ─────────────────────────────────────────────
+// JWT（posimai_token）を優先、なければ旧来の pk_ キーにフォールバック
+function getAuthToken() {
+    return localStorage.getItem('posimai_token') || localStorage.getItem('posimai-brief-apikey') || '';
+}
+function isLoggedIn() { return !!localStorage.getItem('posimai_token'); }
+function getLoginUrl() {
+    return 'https://posimai.soar-enrich.com/login?redirect=' + encodeURIComponent(location.href);
+}
 const DAYS_JP  = ['日','月','火','水','木','金','土'];
 
 // ── 状態 ─────────────────────────────────────────────────────
@@ -675,15 +691,15 @@ function preprocessText(t) {
 }
 
 async function tryVoicevox(text) {
-    const apiKey = localStorage.getItem('posimai-brief-apikey');
-    if (!apiKey) return false;
+    const token = getAuthToken();
+    if (!token) return false;
 
     const ctx = getAudioCtx();
     for (let attempt = 0; attempt < 4; attempt++) {
         if (attempt > 0) await new Promise(r => setTimeout(r, 2000 * attempt));
         const res = await fetch(TTS_API, {
             method: 'POST',
-            headers: { 'Content-Type': 'application/json', 'Authorization': `Bearer ${apiKey}` },
+            headers: { 'Content-Type': 'application/json', 'Authorization': `Bearer ${token}` },
             body: JSON.stringify({ text: preprocessText(text), speaker: ttsSpeaker }),
         });
         if (res.status === 503) {
@@ -944,14 +960,30 @@ function initSpeakerBtns() {
     });
 }
 
-// ── API キー保存 ──────────────────────────────────────────────
-document.getElementById('apiKeyInput').value = localStorage.getItem('posimai-brief-apikey') || '';
-document.getElementById('apiKeySave').addEventListener('click', () => {
-    const v = document.getElementById('apiKeyInput').value.trim();
-    localStorage.setItem('posimai-brief-apikey', v);
-    if (typeof showToast === 'function') showToast('保存しました');
+// ── 認証 UI 初期化 ───────────────────────────────────────────
+function updateAuthUI() {
+    const loggedIn = isLoggedIn();
+    document.getElementById('authLoggedIn').style.display  = loggedIn ? '' : 'none';
+    document.getElementById('authLoggedOut').style.display = loggedIn ? 'none' : '';
+    if (loggedIn) {
+        try {
+            const payload = JSON.parse(atob(localStorage.getItem('posimai_token').split('.')[1]));
+            document.getElementById('authUserLine').textContent = 'ログイン中: ' + (payload.userId || '');
+        } catch (_) {}
+    }
+    document.getElementById('authLoginBtn').href = getLoginUrl();
+    // 音声バッジも更新
+    updateVoiceBadge(!isLoggedIn() && !localStorage.getItem('posimai-brief-apikey'));
+}
+
+document.getElementById('authLogoutBtn').addEventListener('click', () => {
+    localStorage.removeItem('posimai_token');
+    updateAuthUI();
+    if (typeof showToast === 'function') showToast('ログアウトしました');
 });
 
+updateAuthUI();
+
 // ── 日付表示 ─────────────────────────────────────────────────
 function updateDate() {
     const now = new Date();
@@ -967,13 +999,13 @@ async function loadFeed() {
     document.getElementById('briefList').innerHTML     = '';
 
     try {
-        const apiKey = localStorage.getItem('posimai-brief-apikey');
+        const token = getAuthToken();
         let res;
-        if (apiKey) {
+        if (token) {
             let customFeeds = [];
             try {
                 const mediaRes = await fetch(API_BASE + '/feed/media', {
-                    headers: { 'Authorization': `Bearer ${apiKey}` }
+                    headers: { 'Authorization': `Bearer ${token}` }
                 });
                 if (mediaRes.ok) {
                     const medias = await mediaRes.json();
@@ -994,7 +1026,7 @@ async function loadFeed() {
                 res = await fetch(FEED_API, {
                     method: 'POST',
                     cache: 'no-store',
-                    headers: { 'Content-Type': 'application/json', 'Authorization': `Bearer ${apiKey}` },
+                    headers: { 'Content-Type': 'application/json', 'Authorization': `Bearer ${token}` },
                     body: JSON.stringify({ customFeeds }),
                 });
             } catch (_) {