update frontend

static/app.js

@@ -1,5 +1,14 @@
 const API = '';
 let currentSession = null;
+let sendTime = 0;
+
+// Configure marked
+marked.setOptions({
+    breaks: true,
+    gfm: true,
+    headerIds: false,
+    mangle: false,
+});
 
 // DOM
 const sessionList = document.getElementById('session-list');
@@ -97,14 +106,17 @@ async function sendMessage() {
     scrollToBottom();
     btnSend.disabled = true;
 
+    sendTime = performance.now();
+
     try {
         const data = await api(`/api/sessions/${currentSession.id}/messages`, {
             method: 'POST',
             body: JSON.stringify({ content: text }),
         });
 
+        const elapsed = ((performance.now() - sendTime) / 1000).toFixed(1);
         typingEl.remove();
-        appendMessage('assistant', data.content, data.sources);
+        appendMessage('assistant', data.content, data.sources, elapsed);
         scrollToBottom();
         loadSessions();
     } catch (e) {
@@ -117,7 +129,15 @@ async function sendMessage() {
     }
 }
 
-function appendMessage(role, content, sources = null) {
+function renderMarkdown(text) {
+    try {
+        return marked.parse(text || '');
+    } catch {
+        return esc(text);
+    }
+}
+
+function appendMessage(role, content, sources = null, elapsed = null) {
     // Remove empty state if present
     const empty = messages.querySelector('.empty-state');
     if (empty) empty.remove();
@@ -125,14 +145,27 @@ function appendMessage(role, content, sources = null) {
     const div = document.createElement('div');
     div.className = `message ${role}`;
 
-    let html = `<div class="bubble">${esc(content)}</div>`;
+    let html = '';
 
+    if (role === 'assistant') {
+        html += `<div class="bubble">${renderMarkdown(content)}</div>`;
+    } else {
+        html += `<div class="bubble">${esc(content)}</div>`;
+    }
+
+    // Sources + timing
+    const metaParts = [];
     if (sources && sources.length > 0) {
-        html += `<div class="sources">`;
-        sources.forEach(s => {
-            html += `<a class="source-chip" href="${esc(s.url)}" target="_blank" title="${esc(s.title)}">${esc(s.title.substring(0, 40))}</a>`;
-        });
-        html += `</div>`;
+        const chips = sources.map(s =>
+            `<a class="source-chip" href="${esc(s.url)}" target="_blank" title="${esc(s.title)}">${esc(s.title.substring(0, 40))}</a>`
+        ).join('');
+        metaParts.push(`<div class="sources">${chips}</div>`);
+    }
+    if (elapsed !== null && role === 'assistant') {
+        metaParts.push(`<div class="msg-meta"><span class="timing">⚡ ${elapsed}s</span></div>`);
+    }
+    if (metaParts.length) {
+        html += metaParts.join('');
     }
 
     div.innerHTML = html;

static/style.css

@@ -190,10 +190,98 @@ body {
     padding: 12px 16px;
     font-size: 14px;
     line-height: 1.7;
-    white-space: pre-wrap;
     word-break: break-word;
 }
 
+/* Markdown content inside assistant bubble */
+.bubble h1, .bubble h2, .bubble h3, .bubble h4 {
+    margin: 12px 0 6px;
+    font-weight: 600;
+    line-height: 1.3;
+}
+.bubble h1 { font-size: 18px; }
+.bubble h2 { font-size: 16px; }
+.bubble h3 { font-size: 15px; }
+
+.bubble p { margin: 0 0 8px; }
+.bubble p:last-child { margin-bottom: 0; }
+
+.bubble ul, .bubble ol {
+    margin: 6px 0;
+    padding-left: 20px;
+}
+.bubble li { margin: 2px 0; }
+
+.bubble code {
+    background: #ffffff10;
+    padding: 1px 5px;
+    border-radius: 4px;
+    font-size: 13px;
+    font-family: 'SF Mono', 'Consolas', 'Menlo', monospace;
+}
+
+.bubble pre {
+    background: #0a0a0a;
+    border: 1px solid var(--border);
+    border-radius: var(--radius-sm);
+    padding: 10px 12px;
+    margin: 8px 0;
+    overflow-x: auto;
+}
+.bubble pre code {
+    background: none;
+    padding: 0;
+    font-size: 12px;
+    line-height: 1.5;
+}
+
+.bubble blockquote {
+    border-left: 3px solid var(--accent);
+    margin: 8px 0;
+    padding: 4px 12px;
+    color: var(--text-dim);
+}
+
+.bubble a {
+    color: #60a5fa;
+    text-decoration: none;
+}
+.bubble a:hover { text-decoration: underline; }
+
+.bubble table {
+    border-collapse: collapse;
+    margin: 8px 0;
+    width: 100%;
+    font-size: 13px;
+}
+.bubble th, .bubble td {
+    border: 1px solid var(--border);
+    padding: 6px 10px;
+    text-align: left;
+}
+.bubble th { background: #ffffff08; font-weight: 600; }
+
+.bubble strong { font-weight: 600; }
+.bubble em { font-style: italic; }
+
+.message.user .bubble {
+    white-space: pre-wrap;
+}
+
+.msg-meta {
+    font-size: 11px;
+    color: var(--text-muted);
+    padding: 0 4px;
+    display: flex;
+    gap: 8px;
+    align-items: center;
+}
+
+.msg-meta .timing {
+    color: var(--accent);
+    font-weight: 500;
+}
+
 .sources {
     display: flex;
     flex-wrap: wrap;

templates/index.html

@@ -5,6 +5,7 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>Blog RAG Chat</title>
     <link rel="stylesheet" href="/static/style.css">
+    <script src="https://cdn.jsdelivr.net/npm/marked/marked.min.js"></script>
 </head>
 <body>
     <div class="app">