diff --git a/posimai-dev/index.html b/posimai-dev/index.html
index fa996ddb..c227522d 100644
--- a/posimai-dev/index.html
+++ b/posimai-dev/index.html
@@ -13,8 +13,7 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0, viewport-fit=cover">
     <meta name="description" content="posimai development portal">
     <meta name="color-scheme" content="dark light">
-    <meta name="theme-color" content="#0D0D0D" media="(prefers-color-scheme: dark)">
-    <meta name="theme-color" content="#F9FAFB" media="(prefers-color-scheme: light)">
+    <meta name="theme-color" content="#0C1221">
     <meta name="mobile-web-app-capable" content="yes">
     <meta name="apple-mobile-web-app-capable" content="yes">
     <meta name="apple-mobile-web-app-status-bar-style" content="black-translucent">
@@ -38,10 +37,7 @@
             --accent-dim: rgba(167, 139, 250, 0.15);
             --dev-bg: #0C1221;
         }
-        [data-theme="light"] {
-            --accent: #7C3AED;
-            --dev-bg: #0C1221;
-        }
+        [data-theme="light"] { --accent: #7C3AED; }
 
         * { box-sizing: border-box; margin: 0; padding: 0; }
 
@@ -51,91 +47,103 @@
             height: 100dvh;
             overflow: hidden;
             background: var(--dev-bg);
+            font-family: Inter, sans-serif;
         }
 
+        /* ── Header ── */
         .header {
             display: flex;
             align-items: center;
             justify-content: space-between;
             padding: 0 16px;
             height: 48px;
-            border-bottom: 1px solid var(--border);
+            border-bottom: 1px solid rgba(255,255,255,0.06);
             flex-shrink: 0;
+            background: rgba(12, 18, 33, 0.8);
+            backdrop-filter: blur(12px);
         }
-
-        .header-left {
-            display: flex;
-            align-items: center;
-            gap: 10px;
-        }
-
-        .header-dot {
-            width: 8px;
-            height: 8px;
-            border-radius: 50%;
-            background: var(--accent);
-        }
-
-        .header-title {
-            font-size: 14px;
-            font-weight: 600;
-            color: var(--text);
-            letter-spacing: -0.01em;
-        }
+        .header-left { display: flex; align-items: center; gap: 10px; }
+        .header-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--accent); }
+        .header-title { font-size: 14px; font-weight: 600; color: #F3F4F6; letter-spacing: -0.01em; }
+        .header-right { display: flex; align-items: center; gap: 4px; }
 
         .status-badge {
-            font-size: 11px;
-            font-weight: 500;
-            padding: 2px 8px;
-            border-radius: 20px;
-            background: var(--accent-dim);
-            color: var(--accent);
+            font-size: 11px; font-weight: 500; padding: 2px 8px;
+            border-radius: 20px; background: var(--accent-dim); color: var(--accent);
             transition: background 0.2s, color 0.2s;
         }
+        .status-badge.disconnected { background: rgba(239,68,68,0.12); color: #F87171; }
 
-        .status-badge.disconnected {
-            background: rgba(239, 68, 68, 0.12);
-            color: #F87171;
+        .session-badge {
+            font-size: 10px; font-weight: 400; color: rgba(255,255,255,0.3);
+            font-family: monospace; display: none;
         }
+        .session-badge.visible { display: block; }
 
-        .header-right {
-            display: flex;
-            align-items: center;
-            gap: 4px;
+        /* Claude開始ボタン */
+        .claude-btn {
+            display: flex; align-items: center; gap: 6px;
+            padding: 5px 12px; border-radius: 8px; border: none; cursor: pointer;
+            background: var(--accent-dim); color: var(--accent);
+            font-size: 12px; font-weight: 500; font-family: Inter, sans-serif;
+            transition: background 0.15s;
         }
+        .claude-btn:hover { background: rgba(167,139,250,0.25); }
 
+        /* ── Terminal ── */
         #terminal-container {
             flex: 1;
             overflow: hidden;
-            padding: 12px;
+            padding: 12px 12px 0;
             min-height: 0;
             background:
-                radial-gradient(ellipse at 15% 60%, rgba(34, 211, 238, 0.07) 0%, transparent 55%),
-                radial-gradient(ellipse at 85% 25%, rgba(167, 139, 250, 0.07) 0%, transparent 55%),
+                radial-gradient(ellipse at 15% 60%, rgba(34,211,238,0.07) 0%, transparent 55%),
+                radial-gradient(ellipse at 85% 25%, rgba(167,139,250,0.07) 0%, transparent 55%),
                 var(--dev-bg);
         }
+        #terminal-container .xterm { height: 100%; }
+        #terminal-container .xterm-viewport { border-radius: 8px 8px 0 0; }
 
-        #terminal-container .xterm {
-            height: 100%;
+        /* ── Chat input bar ── */
+        .chat-bar {
+            display: flex;
+            align-items: center;
+            gap: 8px;
+            padding: 10px 12px;
+            padding-bottom: max(10px, env(safe-area-inset-bottom));
+            background: rgba(12, 18, 33, 0.9);
+            border-top: 1px solid rgba(255,255,255,0.06);
+            flex-shrink: 0;
         }
-
-        #terminal-container .xterm-viewport {
-            border-radius: 8px;
+        .chat-input {
+            flex: 1;
+            background: rgba(255,255,255,0.05);
+            border: 1px solid rgba(255,255,255,0.08);
+            border-radius: 10px;
+            padding: 9px 14px;
+            color: #F3F4F6;
+            font-size: 14px;
+            font-family: Inter, sans-serif;
+            outline: none;
+            transition: border-color 0.15s;
         }
-
-        /* スマホ用キーボード表示ボタン */
-        #keyboard-btn {
-            display: none;
-        }
-
-        @media (pointer: coarse) {
-            #keyboard-btn {
-                display: flex;
-            }
+        .chat-input::placeholder { color: rgba(255,255,255,0.25); }
+        .chat-input:focus { border-color: rgba(167,139,250,0.4); }
+        .send-btn {
+            width: 38px; height: 38px; border-radius: 10px; border: none;
+            background: var(--accent); color: #0C1221; cursor: pointer;
+            display: flex; align-items: center; justify-content: center;
+            flex-shrink: 0; transition: opacity 0.15s;
         }
+        .send-btn:hover { opacity: 0.85; }
+        .send-btn:disabled { opacity: 0.3; cursor: default; }
 
         .overlay { display: none; }
         .settings-panel { z-index: 1000; }
+
+        /* icon-btn override for dark bg */
+        .icon-btn { color: rgba(255,255,255,0.5); }
+        .icon-btn:hover { color: #F3F4F6; background: rgba(255,255,255,0.06); }
     </style>
 </head>
 <body>
@@ -156,6 +164,13 @@
                 <button class="theme-btn" data-theme-val="system"><i data-lucide="monitor" style="width:12px;height:12px;stroke-width:1.75"></i>自動</button>
             </div>
         </div>
+        <div style="margin-top:20px">
+            <div class="settings-group-label">セッション</div>
+            <a href="/sessions.html" style="font-size:13px;color:var(--accent);text-decoration:none;display:flex;align-items:center;gap:6px;margin-top:8px">
+                <i data-lucide="history" style="width:14px;height:14px;stroke-width:1.75"></i>
+                過去のセッションを見る
+            </a>
+        </div>
     </div>
 </aside>
 <div class="overlay" id="overlay" aria-hidden="true"></div>
@@ -165,10 +180,12 @@
         <div class="header-dot" aria-hidden="true"></div>
         <span class="header-title">posimai-dev</span>
         <span class="status-badge disconnected" id="statusBadge">接続中...</span>
+        <span class="session-badge" id="sessionBadge"></span>
     </div>
     <div class="header-right">
-        <button class="icon-btn" id="keyboard-btn" aria-label="キーボードを表示">
-            <i data-lucide="keyboard" style="width:18px;height:18px;stroke-width:1.5"></i>
+        <button class="claude-btn" id="claudeBtn">
+            <i data-lucide="bot" style="width:13px;height:13px;stroke-width:1.75"></i>
+            Claude 開始
         </button>
         <button class="icon-btn" id="settingsBtn" aria-label="設定" aria-expanded="false">
             <i data-lucide="settings" style="width:18px;height:18px;stroke-width:1.5"></i>
@@ -178,13 +195,33 @@
 
 <div id="terminal-container"></div>
 
+<div class="chat-bar">
+    <input
+        type="text"
+        class="chat-input"
+        id="chatInput"
+        placeholder="Claude に話しかける、またはコマンドを入力..."
+        autocomplete="off"
+        autocorrect="off"
+        autocapitalize="off"
+        spellcheck="false"
+    >
+    <button class="send-btn" id="sendBtn" disabled aria-label="送信">
+        <i data-lucide="arrow-up" style="width:16px;height:16px;stroke-width:2.5"></i>
+    </button>
+</div>
+
 <script src="https://posimai-ui.vercel.app/v1/base.js" defer></script>
 <script>
 (function () {
     const statusBadge = document.getElementById('statusBadge');
-    const container = document.getElementById('terminal-container');
+    const sessionBadge = document.getElementById('sessionBadge');
+    const container   = document.getElementById('terminal-container');
+    const chatInput   = document.getElementById('chatInput');
+    const sendBtn     = document.getElementById('sendBtn');
+    const claudeBtn   = document.getElementById('claudeBtn');
 
-    // xterm.js setup
+    // xterm.js
     const term = new Terminal({
         fontFamily: '"JetBrains Mono", "Fira Code", "Cascadia Code", monospace',
         fontSize: 14,
@@ -195,55 +232,55 @@
             background: 'rgba(12, 18, 33, 0.0)',
             foreground: '#F3F4F6',
             cursor: '#A78BFA',
-            selectionBackground: 'rgba(167, 139, 250, 0.3)',
-            black: '#1A1A1A',
-            brightBlack: '#4B5563',
-            red: '#F87171',
-            brightRed: '#FCA5A5',
-            green: '#6EE7B7',
-            brightGreen: '#A7F3D0',
-            yellow: '#FCD34D',
-            brightYellow: '#FDE68A',
-            blue: '#60A5FA',
-            brightBlue: '#93C5FD',
-            magenta: '#A78BFA',
-            brightMagenta: '#C4B5FD',
-            cyan: '#22D3EE',
-            brightCyan: '#67E8F9',
-            white: '#F3F4F6',
-            brightWhite: '#FFFFFF'
+            selectionBackground: 'rgba(167,139,250,0.3)',
+            black: '#1A1A1A', brightBlack: '#4B5563',
+            red: '#F87171',   brightRed: '#FCA5A5',
+            green: '#6EE7B7', brightGreen: '#A7F3D0',
+            yellow: '#FCD34D',brightYellow: '#FDE68A',
+            blue: '#60A5FA',  brightBlue: '#93C5FD',
+            magenta: '#A78BFA', brightMagenta: '#C4B5FD',
+            cyan: '#22D3EE',  brightCyan: '#67E8F9',
+            white: '#F3F4F6', brightWhite: '#FFFFFF'
         }
     });
-
     const fitAddon = new FitAddon.FitAddon();
     term.loadAddon(fitAddon);
     term.open(container);
     fitAddon.fit();
 
-    // WebSocket connection
+    // WebSocket
     const proto = location.protocol === 'https:' ? 'wss:' : 'ws:';
     let ws;
 
+    function sendInput(text) {
+        if (ws && ws.readyState === 1) ws.send(JSON.stringify({ type: 'input', data: text }));
+    }
+
     function connect() {
         ws = new WebSocket(`${proto}//${location.host}/terminal`);
 
         ws.onopen = () => {
             statusBadge.textContent = '接続済み';
             statusBadge.classList.remove('disconnected');
-            const { cols, rows } = term;
-            ws.send(JSON.stringify({ type: 'resize', cols, rows }));
+            sendBtn.disabled = false;
+            ws.send(JSON.stringify({ type: 'resize', cols: term.cols, rows: term.rows }));
         };
 
         ws.onmessage = (e) => {
             try {
                 const msg = JSON.parse(e.data);
                 if (msg.type === 'output') term.write(msg.data);
+                if (msg.type === 'session') {
+                    sessionBadge.textContent = msg.id;
+                    sessionBadge.classList.add('visible');
+                }
             } catch {}
         };
 
         ws.onclose = () => {
             statusBadge.textContent = '切断';
             statusBadge.classList.add('disconnected');
+            sendBtn.disabled = true;
             term.write('\r\n\x1b[31m[切断されました。再接続中...]\x1b[0m\r\n');
             setTimeout(connect, 3000);
         };
@@ -253,42 +290,45 @@
 
     connect();
 
-    // Terminal input
-    term.onData((data) => {
-        if (ws && ws.readyState === 1) {
-            ws.send(JSON.stringify({ type: 'input', data }));
-        }
+    // ターミナル直接入力
+    term.onData((data) => sendInput(data));
+
+    // チャットバー送信
+    function submitChat() {
+        const text = chatInput.value.trim();
+        if (!text) return;
+        sendInput(text + '\n');
+        chatInput.value = '';
+        term.focus();
+    }
+
+    sendBtn.addEventListener('click', submitChat);
+    chatInput.addEventListener('keydown', (e) => {
+        if (e.key === 'Enter' && !e.shiftKey) { e.preventDefault(); submitChat(); }
     });
 
-    // Resize handling
-    const ro = new ResizeObserver(() => {
-        fitAddon.fit();
-        if (ws && ws.readyState === 1) {
-            ws.send(JSON.stringify({ type: 'resize', cols: term.cols, rows: term.rows }));
-        }
-    });
-    ro.observe(container);
-
-    window.addEventListener('resize', () => {
-        fitAddon.fit();
-    });
-
-    // スマホ用キーボードボタン
-    document.getElementById('keyboard-btn').addEventListener('click', () => {
+    // Claude 開始ボタン
+    claudeBtn.addEventListener('click', () => {
+        sendInput('claude\n');
         term.focus();
     });
 
-    // Settings panel
-    const settingsBtn = document.getElementById('settingsBtn');
-    const settingsPanel = document.getElementById('settingsPanel');
-    const settingsCloseBtn = document.getElementById('settingsCloseBtn');
+    // Resize
+    const ro = new ResizeObserver(() => {
+        fitAddon.fit();
+        if (ws && ws.readyState === 1) ws.send(JSON.stringify({ type: 'resize', cols: term.cols, rows: term.rows }));
+    });
+    ro.observe(container);
+    window.addEventListener('resize', () => fitAddon.fit());
 
+    // Settings panel
+    const settingsBtn   = document.getElementById('settingsBtn');
+    const settingsPanel = document.getElementById('settingsPanel');
     settingsBtn.addEventListener('click', () => {
         settingsPanel.classList.toggle('open');
         settingsBtn.setAttribute('aria-expanded', settingsPanel.classList.contains('open'));
     });
-
-    settingsCloseBtn.addEventListener('click', () => {
+    document.getElementById('settingsCloseBtn').addEventListener('click', () => {
         settingsPanel.classList.remove('open');
         settingsBtn.setAttribute('aria-expanded', 'false');
     });
diff --git a/posimai-dev/server.js b/posimai-dev/server.js
index c58b51e2..22a38726 100644
--- a/posimai-dev/server.js
+++ b/posimai-dev/server.js
@@ -11,9 +11,33 @@ const os = require('os');
 const app = express();
 const PORT = process.env.PORT || 3333;
 
+// セッションログ保存ディレクトリ
+const SESSIONS_DIR = path.join(os.homedir(), 'posimai-dev-sessions');
+if (!fs.existsSync(SESSIONS_DIR)) fs.mkdirSync(SESSIONS_DIR, { recursive: true });
+
+app.use(express.json());
 app.use(express.static(path.join(__dirname)));
 
-// ホームディレクトリのTailscale証明書を自動検出
+// セッション一覧 API
+app.get('/api/sessions', (req, res) => {
+  const files = fs.readdirSync(SESSIONS_DIR)
+    .filter((f) => f.endsWith('.log'))
+    .map((f) => {
+      const stat = fs.statSync(path.join(SESSIONS_DIR, f));
+      return { id: f.replace('.log', ''), size: stat.size, mtime: stat.mtime };
+    })
+    .sort((a, b) => new Date(b.mtime) - new Date(a.mtime));
+  res.json(files);
+});
+
+// セッション内容 API
+app.get('/api/sessions/:id', (req, res) => {
+  const file = path.join(SESSIONS_DIR, req.params.id + '.log');
+  if (!fs.existsSync(file)) return res.status(404).json({ error: 'not found' });
+  res.type('text/plain').send(fs.readFileSync(file, 'utf8'));
+});
+
+// Tailscale証明書を自動検出
 function findCert() {
   const home = os.homedir();
   const crt = fs.readdirSync(home).find((f) => f.endsWith('.crt'));
@@ -30,30 +54,47 @@ const proto = tlsOpts ? 'https' : 'http';
 const wss = new WebSocketServer({ server, path: '/terminal' });
 
 wss.on('connection', (ws) => {
+  // セッションID・ログファイル作成
+  const sessionId = new Date().toISOString().replace(/[:.]/g, '-').slice(0, 19);
+  const logPath = path.join(SESSIONS_DIR, `${sessionId}.log`);
+  const logStream = fs.createWriteStream(logPath, { flags: 'a' });
+  logStream.write(`=== posimai-dev session ${sessionId} ===\n`);
+
+  // セッションID をブラウザに通知
+  ws.send(JSON.stringify({ type: 'session', id: sessionId }));
+
   const shell = process.env.SHELL || '/bin/bash';
   const ptyProc = pty.spawn(shell, [], {
     name: 'xterm-256color',
     cols: 80,
     rows: 24,
-    cwd: process.env.HOME || '/home/ubuntu-pc',
-    env: process.env
+    cwd: path.join(os.homedir(), 'posimai-project'),
+    env: { ...process.env, PATH: `${os.homedir()}/.npm-global/bin:${process.env.PATH}` }
   });
 
+  // 起動時に posimai-project へ自動移動（cwd で指定済みだが source bashrc も通す）
+  setTimeout(() => ptyProc.write(`source ~/.bashrc\n`), 300);
+
   ptyProc.onData((data) => {
-    if (ws.readyState === 1) {
-      ws.send(JSON.stringify({ type: 'output', data }));
-    }
+    logStream.write(data);
+    if (ws.readyState === 1) ws.send(JSON.stringify({ type: 'output', data }));
   });
 
   ws.on('message', (raw) => {
     try {
       const msg = JSON.parse(raw.toString());
-      if (msg.type === 'input') ptyProc.write(msg.data);
+      if (msg.type === 'input') {
+        logStream.write(msg.data);
+        ptyProc.write(msg.data);
+      }
       if (msg.type === 'resize') ptyProc.resize(Number(msg.cols), Number(msg.rows));
     } catch {}
   });
 
-  ws.on('close', () => { try { ptyProc.kill(); } catch {} });
+  ws.on('close', () => {
+    logStream.end(`\n=== session end ===\n`);
+    try { ptyProc.kill(); } catch {}
+  });
   ptyProc.onExit(() => { try { ws.close(); } catch {} });
 });
 
diff --git a/posimai-dev/sessions.html b/posimai-dev/sessions.html
new file mode 100644
index 00000000..8c0065e1
--- /dev/null
+++ b/posimai-dev/sessions.html
@@ -0,0 +1,327 @@
+<!DOCTYPE html>
+<html lang="ja" data-app-id="posimai-dev">
+<head>
+    <meta charset="UTF-8">
+    <meta name="robots" content="noindex, nofollow">
+    <script>
+    (function () {
+        var t = localStorage.getItem('posimai-dev-theme') || 'dark';
+        document.documentElement.setAttribute('data-theme', t === 'light' ? 'light' : 'dark');
+        document.documentElement.setAttribute('data-theme-pref', t);
+    })();
+    </script>
+    <meta name="viewport" content="width=device-width, initial-scale=1.0, viewport-fit=cover">
+    <meta name="description" content="posimai-dev session history">
+    <meta name="color-scheme" content="dark light">
+    <meta name="theme-color" content="#0C1221">
+    <title>セッション履歴 — posimai-dev</title>
+    <link rel="preconnect" href="https://fonts.googleapis.com">
+    <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
+    <link href="https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600&display=swap" rel="stylesheet">
+    <link rel="stylesheet" href="https://posimai-ui.vercel.app/v1/base.css">
+    <script src="https://unpkg.com/lucide@0.344.0/dist/umd/lucide.min.js"></script>
+    <style>
+        :root {
+            --accent: #A78BFA;
+            --accent-dim: rgba(167, 139, 250, 0.15);
+            --dev-bg: #0C1221;
+        }
+        [data-theme="light"] { --accent: #7C3AED; }
+
+        * { box-sizing: border-box; margin: 0; padding: 0; }
+
+        body {
+            display: flex;
+            flex-direction: column;
+            min-height: 100dvh;
+            background:
+                radial-gradient(ellipse at 15% 60%, rgba(34,211,238,0.07) 0%, transparent 55%),
+                radial-gradient(ellipse at 85% 25%, rgba(167,139,250,0.07) 0%, transparent 55%),
+                var(--dev-bg);
+            font-family: Inter, sans-serif;
+            color: #F3F4F6;
+        }
+
+        .header {
+            display: flex;
+            align-items: center;
+            justify-content: space-between;
+            padding: 0 16px;
+            height: 48px;
+            border-bottom: 1px solid rgba(255,255,255,0.06);
+            flex-shrink: 0;
+            background: rgba(12, 18, 33, 0.8);
+            backdrop-filter: blur(12px);
+            position: sticky;
+            top: 0;
+            z-index: 10;
+        }
+        .header-left { display: flex; align-items: center; gap: 10px; }
+        .header-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--accent); }
+        .header-title { font-size: 14px; font-weight: 600; color: #F3F4F6; letter-spacing: -0.01em; }
+
+        .back-btn {
+            display: flex; align-items: center; gap: 6px;
+            padding: 5px 12px; border-radius: 8px; border: none; cursor: pointer;
+            background: var(--accent-dim); color: var(--accent);
+            font-size: 12px; font-weight: 500; font-family: Inter, sans-serif;
+            text-decoration: none;
+            transition: background 0.15s;
+        }
+        .back-btn:hover { background: rgba(167,139,250,0.25); }
+
+        .content {
+            flex: 1;
+            padding: 24px 16px;
+            max-width: 800px;
+            width: 100%;
+            margin: 0 auto;
+        }
+
+        .page-title {
+            font-size: 18px;
+            font-weight: 600;
+            margin-bottom: 4px;
+            letter-spacing: -0.02em;
+        }
+        .page-subtitle {
+            font-size: 13px;
+            color: rgba(255,255,255,0.35);
+            margin-bottom: 20px;
+        }
+
+        .session-list { display: flex; flex-direction: column; gap: 8px; }
+
+        .session-card {
+            background: rgba(255,255,255,0.04);
+            border: 1px solid rgba(255,255,255,0.07);
+            border-radius: 12px;
+            padding: 14px 16px;
+            cursor: pointer;
+            transition: background 0.15s, border-color 0.15s;
+            display: flex;
+            align-items: center;
+            gap: 12px;
+        }
+        .session-card:hover { background: rgba(167,139,250,0.08); border-color: rgba(167,139,250,0.2); }
+        .session-card.active { background: rgba(167,139,250,0.1); border-color: rgba(167,139,250,0.3); }
+
+        .session-icon {
+            width: 36px; height: 36px; border-radius: 8px;
+            background: var(--accent-dim);
+            display: flex; align-items: center; justify-content: center;
+            flex-shrink: 0;
+        }
+
+        .session-info { flex: 1; min-width: 0; }
+        .session-id {
+            font-size: 13px; font-weight: 500; font-family: monospace;
+            color: #F3F4F6; white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
+        }
+        .session-meta {
+            font-size: 11px; color: rgba(255,255,255,0.35); margin-top: 2px;
+        }
+
+        .session-size {
+            font-size: 11px; color: rgba(255,255,255,0.3);
+            font-family: monospace; flex-shrink: 0;
+        }
+
+        /* ログビューアー */
+        .log-viewer {
+            display: none;
+            margin-top: 16px;
+            background: rgba(0,0,0,0.3);
+            border: 1px solid rgba(255,255,255,0.07);
+            border-radius: 12px;
+            overflow: hidden;
+        }
+        .log-viewer.open { display: block; }
+
+        .log-header {
+            display: flex; align-items: center; justify-content: space-between;
+            padding: 10px 14px;
+            border-bottom: 1px solid rgba(255,255,255,0.06);
+            background: rgba(255,255,255,0.03);
+        }
+        .log-header-title { font-size: 12px; color: rgba(255,255,255,0.5); font-family: monospace; }
+
+        .log-close-btn {
+            background: none; border: none; cursor: pointer;
+            color: rgba(255,255,255,0.4); padding: 2px;
+            display: flex; align-items: center;
+            transition: color 0.15s;
+        }
+        .log-close-btn:hover { color: #F3F4F6; }
+
+        .log-body {
+            padding: 14px;
+            font-family: "JetBrains Mono", "Fira Code", monospace;
+            font-size: 12px;
+            line-height: 1.6;
+            color: #B0BAD3;
+            white-space: pre-wrap;
+            word-break: break-all;
+            max-height: 400px;
+            overflow-y: auto;
+        }
+
+        .empty-state {
+            text-align: center;
+            padding: 60px 20px;
+            color: rgba(255,255,255,0.25);
+        }
+        .empty-state-icon { margin-bottom: 12px; }
+        .empty-state-text { font-size: 14px; }
+
+        .loading {
+            text-align: center;
+            padding: 40px;
+            color: rgba(255,255,255,0.3);
+            font-size: 13px;
+        }
+
+        .icon-btn { color: rgba(255,255,255,0.5); }
+        .icon-btn:hover { color: #F3F4F6; background: rgba(255,255,255,0.06); }
+    </style>
+</head>
+<body>
+
+<header class="header">
+    <div class="header-left">
+        <div class="header-dot" aria-hidden="true"></div>
+        <span class="header-title">セッション履歴</span>
+    </div>
+    <a href="/" class="back-btn">
+        <i data-lucide="arrow-left" style="width:13px;height:13px;stroke-width:1.75"></i>
+        ターミナルに戻る
+    </a>
+</header>
+
+<div class="content">
+    <div class="page-title">過去のセッション</div>
+    <div class="page-subtitle" id="sessionCount">読み込み中...</div>
+
+    <div class="session-list" id="sessionList">
+        <div class="loading">読み込み中...</div>
+    </div>
+
+    <div class="log-viewer" id="logViewer">
+        <div class="log-header">
+            <span class="log-header-title" id="logTitle"></span>
+            <button class="log-close-btn" id="logCloseBtn" aria-label="閉じる">
+                <i data-lucide="x" style="width:14px;height:14px;stroke-width:1.75"></i>
+            </button>
+        </div>
+        <div class="log-body" id="logBody"></div>
+    </div>
+</div>
+
+<script src="https://posimai-ui.vercel.app/v1/base.js" defer></script>
+<script>
+(function () {
+    const sessionList  = document.getElementById('sessionList');
+    const sessionCount = document.getElementById('sessionCount');
+    const logViewer    = document.getElementById('logViewer');
+    const logTitle     = document.getElementById('logTitle');
+    const logBody      = document.getElementById('logBody');
+
+    let activeCard = null;
+
+    function formatDate(iso) {
+        const d = new Date(iso);
+        return d.toLocaleString('ja-JP', { month: 'numeric', day: 'numeric', hour: '2-digit', minute: '2-digit' });
+    }
+
+    function formatSize(bytes) {
+        if (bytes < 1024) return bytes + ' B';
+        return (bytes / 1024).toFixed(1) + ' KB';
+    }
+
+    // ANSIエスケープを除去して表示
+    function stripAnsi(str) {
+        return str.replace(/\x1b\[[0-9;]*[mGKHFJ]/g, '').replace(/\r/g, '');
+    }
+
+    async function loadLog(id) {
+        logBody.textContent = '読み込み中...';
+        logTitle.textContent = id + '.log';
+        logViewer.classList.add('open');
+        logViewer.scrollIntoView({ behavior: 'smooth', block: 'nearest' });
+        try {
+            const r = await fetch(`/api/sessions/${encodeURIComponent(id)}`);
+            const text = await r.text();
+            logBody.textContent = stripAnsi(text);
+        } catch (e) {
+            logBody.textContent = '読み込みに失敗しました。';
+        }
+    }
+
+    document.getElementById('logCloseBtn').addEventListener('click', () => {
+        logViewer.classList.remove('open');
+        if (activeCard) { activeCard.classList.remove('active'); activeCard = null; }
+    });
+
+    async function loadSessions() {
+        try {
+            const r = await fetch('/api/sessions');
+            const sessions = await r.json();
+
+            if (!sessions.length) {
+                sessionList.innerHTML = `
+                    <div class="empty-state">
+                        <div class="empty-state-icon">
+                            <i data-lucide="inbox" style="width:32px;height:32px;stroke-width:1;color:rgba(255,255,255,0.15)"></i>
+                        </div>
+                        <div class="empty-state-text">セッションはまだありません</div>
+                    </div>`;
+                sessionCount.textContent = 'セッションなし';
+                lucide.createIcons();
+                return;
+            }
+
+            sessionCount.textContent = `${sessions.length} セッション`;
+            sessionList.innerHTML = '';
+
+            sessions.forEach((s) => {
+                const card = document.createElement('div');
+                card.className = 'session-card';
+                card.innerHTML = `
+                    <div class="session-icon">
+                        <i data-lucide="terminal" style="width:16px;height:16px;stroke-width:1.75;color:var(--accent)"></i>
+                    </div>
+                    <div class="session-info">
+                        <div class="session-id">${s.id}</div>
+                        <div class="session-meta">${formatDate(s.mtime)}</div>
+                    </div>
+                    <div class="session-size">${formatSize(s.size)}</div>`;
+
+                card.addEventListener('click', () => {
+                    if (activeCard === card) {
+                        logViewer.classList.remove('open');
+                        card.classList.remove('active');
+                        activeCard = null;
+                        return;
+                    }
+                    if (activeCard) activeCard.classList.remove('active');
+                    activeCard = card;
+                    card.classList.add('active');
+                    loadLog(s.id);
+                });
+
+                sessionList.appendChild(card);
+            });
+
+            lucide.createIcons();
+        } catch (e) {
+            sessionList.innerHTML = `<div class="empty-state"><div class="empty-state-text">読み込みに失敗しました</div></div>`;
+            sessionCount.textContent = 'エラー';
+        }
+    }
+
+    loadSessions();
+    lucide.createIcons();
+})();
+</script>
+</body>
+</html>