diff --git a/oauth/src/components/AuthButton.jsx b/oauth/src/components/AuthButton.jsx
index ba95f99..2a51fc7 100644
--- a/oauth/src/components/AuthButton.jsx
+++ b/oauth/src/components/AuthButton.jsx
@@ -25,20 +25,20 @@ export default function AuthButton({ user, onLogin, onLogout, loading }) {
 
   if (user) {
     return (
-      <div style={{ display: 'flex', alignItems: 'center', gap: '8px' }}>
+      <div className="user-section" style={{ display: 'flex', alignItems: 'center', gap: '8px' }}>
         {user.avatar && (
           <img 
             src={user.avatar} 
             alt="Profile" 
-            className="avatar"
+            className="user-avatar"
             style={{ width: '24px', height: '24px' }}
           />
         )}
         <div>
-          <div className="display-name" style={{ fontSize: '14px', fontWeight: '700' }}>
+          <div className="user-display-name" style={{ fontSize: '14px', fontWeight: '700' }}>
             {user.displayName}
           </div>
-          <div className="handle" style={{ fontSize: '12px' }}>
+          <div className="user-handle" style={{ fontSize: '12px' }}>
             @{user.handle}
           </div>
         </div>
diff --git a/oauth/src/components/CommentForm.jsx b/oauth/src/components/CommentForm.jsx
index 1f7c615..2f7133d 100644
--- a/oauth/src/components/CommentForm.jsx
+++ b/oauth/src/components/CommentForm.jsx
@@ -4,19 +4,18 @@ import { env } from '../config/env.js'
 
 export default function CommentForm({ user, agent, onCommentPosted }) {
   const [text, setText] = useState('')
-  const [url, setUrl] = useState('')
   const [loading, setLoading] = useState(false)
   const [error, setError] = useState(null)
 
   const handleSubmit = async (e) => {
     e.preventDefault()
-    if (!text.trim() || !url.trim()) return
+    if (!text.trim()) return
 
     setLoading(true)
     setError(null)
 
     try {
-      const currentUrl = url.trim()
+      const currentUrl = window.location.href
       const timestamp = new Date().toISOString()
       
       // Create ai.syui.log record structure (new unified format)
@@ -30,7 +29,7 @@ export default function CommentForm({ user, agent, onCommentPosted }) {
           post: {
             url: currentUrl,
             date: timestamp,
-            slug: new URL(currentUrl).pathname.split('/').pop()?.replace(/\.html$/, '') || '',
+            slug: currentUrl.match(/\/posts\/([^/]+)/)?.[1] || new URL(currentUrl).pathname.split('/').pop()?.replace(/\.html$/, '') || '',
             tags: [],
             title: document.title || 'Comment',
             language: 'ja'
@@ -55,7 +54,6 @@ export default function CommentForm({ user, agent, onCommentPosted }) {
 
       // Clear form
       setText('')
-      setUrl('')
 
       // Notify parent component
       if (onCommentPosted) {
@@ -86,18 +84,8 @@ export default function CommentForm({ user, agent, onCommentPosted }) {
       <h3>コメントを投稿</h3>
       
       <form onSubmit={handleSubmit}>
-        <div className="form-group">
-          <label htmlFor="comment-url">ページURL:</label>
-          <input
-            id="comment-url"
-            type="url"
-            value={url}
-            onChange={(e) => setUrl(e.target.value)}
-            placeholder="https://syui.ai/posts/example"
-            required
-            disabled={loading}
-            className="form-input"
-          />
+        <div className="form-group" style={{ marginBottom: '12px', padding: '8px', backgroundColor: 'var(--background-secondary)', borderRadius: '4px', fontSize: '0.9em' }}>
+          <strong>投稿先:</strong> {window.location.href}
         </div>
 
         <div className="form-group">
@@ -123,7 +111,7 @@ export default function CommentForm({ user, agent, onCommentPosted }) {
         <div className="form-actions">
           <button 
             type="submit" 
-            disabled={loading || !text.trim() || !url.trim()}
+            disabled={loading || !text.trim()}
             className="btn btn-primary"
           >
             {loading ? '投稿中...' : 'コメントを投稿'}
diff --git a/oauth/src/components/OAuthCallback.jsx b/oauth/src/components/OAuthCallback.jsx
index f61b444..0b7b0ed 100644
--- a/oauth/src/components/OAuthCallback.jsx
+++ b/oauth/src/components/OAuthCallback.jsx
@@ -20,11 +20,15 @@ export default function OAuthCallback({ onAuthSuccess }) {
       }
 
       if (code) {
-        setStatus('認証成功！メインページに戻ります...')
+        setStatus('認証成功！元のページに戻ります...')
         
-        // 少し待ってからメインページにリダイレクト
+        // Get the referring page or use root
+        const referrer = document.referrer || window.location.origin
+        const returnUrl = referrer.includes('/oauth/callback') ? window.location.origin : referrer
+        
+        // 少し待ってから元のページにリダイレクト
         setTimeout(() => {
-          window.location.href = '/'
+          window.location.href = returnUrl
         }, 1500)
       } else {
         setStatus('認証情報が見つかりません')