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+<!DOCTYPE html>
+<html lang="zh-CN">
+<head>
+<meta charset="UTF-8">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
+<title>Frost MQTT Client</title>
+<style>
+  :root {
+    --bg-primary: #f8f9fb;
+    --bg-secondary: #ffffff;
+    --bg-tertiary: #f0f2f5;
+    --bg-hover: #e8ecf1;
+    --bg-active: #dce3eb;
+    --border: #e2e6ea;
+    --border-light: #eef0f3;
+    --text-primary: #1a1d23;
+    --text-secondary: #5a5f6b;
+    --text-tertiary: #8b909e;
+    --text-muted: #b0b5c0;
+    --accent: #0ea5a0;
+    --accent-hover: #0b8c87;
+    --accent-light: #e6f7f6;
+    --accent-subtle: #f0faf9;
+    --success: #22c55e;
+    --success-light: #e6f9ef;
+    --warning: #f59e0b;
+    --warning-light: #fff8eb;
+    --danger: #ef4444;
+    --danger-light: #fef0f0;
+    --info: #3b82f6;
+    --info-light: #eff5ff;
+    --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
+    --shadow-md: 0 4px 12px rgba(0,0,0,0.06);
+    --shadow-lg: 0 8px 24px rgba(0,0,0,0.08);
+    --radius-sm: 6px;
+    --radius-md: 10px;
+    --radius-lg: 14px;
+    --radius-xl: 18px;
+    --font-sans: 'Segoe UI', system-ui, -apple-system, sans-serif;
+    --font-mono: 'Cascadia Code', 'Fira Code', 'JetBrains Mono', 'Consolas', monospace;
+    --sidebar-width: 300px;
+  }
+
+  * { margin: 0; padding: 0; box-sizing: border-box; }
+
+  body {
+    font-family: var(--font-sans);
+    background: var(--bg-primary);
+    color: var(--text-primary);
+    height: 100vh;
+    display: flex;
+    overflow: hidden;
+    -webkit-font-smoothing: antialiased;
+  }
+
+  /* ===== Scrollbar ===== */
+  ::-webkit-scrollbar { width: 5px; height: 5px; }
+  ::-webkit-scrollbar-track { background: transparent; }
+  ::-webkit-scrollbar-thumb { background: var(--border); border-radius: 10px; }
+  ::-webkit-scrollbar-thumb:hover { background: var(--text-muted); }
+
+  /* ===== Sidebar ===== */
+  .sidebar {
+    width: var(--sidebar-width);
+    min-width: var(--sidebar-width);
+    background: var(--bg-secondary);
+    border-right: 1px solid var(--border);
+    display: flex;
+    flex-direction: column;
+    z-index: 10;
+  }
+
+  .sidebar-header {
+    padding: 18px 20px;
+    border-bottom: 1px solid var(--border-light);
+    display: flex;
+    align-items: center;
+    gap: 10px;
+    flex-shrink: 0;
+  }
+
+  .sidebar-logo {
+    width: 34px;
+    height: 34px;
+    background: var(--accent);
+    border-radius: var(--radius-sm);
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    color: white;
+    font-size: 18px;
+    font-weight: 700;
+    flex-shrink: 0;
+  }
+
+  .sidebar-title {
+    font-size: 15px;
+    font-weight: 700;
+    color: var(--text-primary);
+    letter-spacing: -0.01em;
+  }
+
+  .sidebar-subtitle {
+    font-size: 11px;
+    color: var(--text-tertiary);
+    font-weight: 500;
+  }
+
+  .server-list {
+    flex: 1;
+    overflow-y: auto;
+    padding: 8px;
+  }
+
+  .server-item {
+    padding: 10px 12px;
+    border-radius: var(--radius-md);
+    cursor: pointer;
+    margin-bottom: 4px;
+    transition: all 0.15s ease;
+    border: 1px solid transparent;
+    position: relative;
+  }
+
+  .server-item:hover {
+    background: var(--bg-tertiary);
+  }
+
+  .server-item.active {
+    background: var(--accent-subtle);
+    border-color: var(--accent);
+  }
+
+  .server-item-header {
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+    gap: 8px;
+  }
+
+  .server-item-name {
+    font-size: 13px;
+    font-weight: 600;
+    color: var(--text-primary);
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+  }
+
+  .server-item-url {
+    font-size: 11px;
+    color: var(--text-tertiary);
+    font-family: var(--font-mono);
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    margin-top: 2px;
+  }
+
+  .status-dot {
+    width: 8px;
+    height: 8px;
+    border-radius: 50%;
+    flex-shrink: 0;
+  }
+
+  .status-dot.disconnected { background: var(--text-muted); }
+  .status-dot.connecting { background: var(--warning); animation: pulse 1s infinite; }
+  .status-dot.connected { background: var(--success); }
+  .status-dot.error { background: var(--danger); }
+
+  @keyframes pulse {
+    0%, 100% { opacity: 1; }
+    50% { opacity: 0.4; }
+  }
+
+  .server-item-actions {
+    display: flex;
+    gap: 4px;
+    opacity: 0;
+    transition: opacity 0.15s;
+  }
+
+  .server-item:hover .server-item-actions { opacity: 1; }
+
+  .icon-btn {
+    width: 28px;
+    height: 28px;
+    border: none;
+    border-radius: var(--radius-sm);
+    background: transparent;
+    cursor: pointer;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    color: var(--text-tertiary);
+    transition: all 0.15s;
+    font-size: 14px;
+  }
+
+  .icon-btn:hover {
+    background: var(--bg-hover);
+    color: var(--text-primary);
+  }
+
+  .icon-btn.danger:hover {
+    background: var(--danger-light);
+    color: var(--danger);
+  }
+
+  .sidebar-footer {
+    padding: 10px 12px;
+    border-top: 1px solid var(--border-light);
+    flex-shrink: 0;
+  }
+
+  .btn {
+    display: inline-flex;
+    align-items: center;
+    justify-content: center;
+    gap: 6px;
+    padding: 8px 16px;
+    border-radius: var(--radius-sm);
+    border: 1px solid transparent;
+    font-size: 13px;
+    font-weight: 600;
+    cursor: pointer;
+    transition: all 0.15s;
+    font-family: var(--font-sans);
+    white-space: nowrap;
+  }
+
+  .btn-primary {
+    background: var(--accent);
+    color: #fff;
+    border-color: var(--accent);
+  }
+  .btn-primary:hover {
+    background: var(--accent-hover);
+    border-color: var(--accent-hover);
+  }
+
+  .btn-outline {
+    background: var(--bg-secondary);
+    color: var(--text-primary);
+    border-color: var(--border);
+  }
+  .btn-outline:hover {
+    background: var(--bg-tertiary);
+    border-color: var(--text-muted);
+  }
+
+  .btn-sm {
+    padding: 5px 10px;
+    font-size: 12px;
+    border-radius: var(--radius-sm);
+  }
+
+  .btn-xs {
+    padding: 3px 8px;
+    font-size: 11px;
+    border-radius: 4px;
+  }
+
+  .btn-success {
+    background: var(--success);
+    color: #fff;
+    border-color: var(--success);
+  }
+  .btn-success:hover {
+    background: #1ca04a;
+  }
+
+  .btn-danger {
+    background: var(--danger);
+    color: #fff;
+    border-color: var(--danger);
+  }
+  .btn-danger:hover {
+    background: #dc2626;
+  }
+
+  .btn-warning {
+    background: var(--warning);
+    color: #fff;
+    border-color: var(--warning);
+  }
+
+  .btn-full {
+    width: 100%;
+  }
+
+  /* ===== Main Content ===== */
+  .main {
+    flex: 1;
+    display: flex;
+    flex-direction: column;
+    min-width: 0;
+    background: var(--bg-primary);
+  }
+
+  .main-header {
+    background: var(--bg-secondary);
+    border-bottom: 1px solid var(--border);
+    padding: 0 24px;
+    display: flex;
+    align-items: center;
+    gap: 4px;
+    flex-shrink: 0;
+    height: 50px;
+  }
+
+  .tab-btn {
+    padding: 8px 16px;
+    border: none;
+    background: transparent;
+    cursor: pointer;
+    font-size: 13px;
+    font-weight: 500;
+    color: var(--text-tertiary);
+    border-bottom: 2px solid transparent;
+    margin-bottom: -1px;
+    transition: all 0.15s;
+    font-family: var(--font-sans);
+    display: flex;
+    align-items: center;
+    gap: 6px;
+  }
+
+  .tab-btn:hover { color: var(--text-primary); }
+  .tab-btn.active {
+    color: var(--accent);
+    border-bottom-color: var(--accent);
+    font-weight: 600;
+  }
+
+  .tab-icon {
+    font-size: 15px;
+  }
+
+  .main-content {
+    flex: 1;
+    overflow-y: auto;
+    padding: 20px 24px;
+  }
+
+  .tab-panel { display: none; }
+  .tab-panel.active { display: block; }
+
+  /* ===== Cards ===== */
+  .card {
+    background: var(--bg-secondary);
+    border: 1px solid var(--border);
+    border-radius: var(--radius-lg);
+    padding: 20px;
+    margin-bottom: 16px;
+    box-shadow: var(--shadow-sm);
+  }
+
+  .card-header {
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+    margin-bottom: 16px;
+  }
+
+  .card-title {
+    font-size: 14px;
+    font-weight: 700;
+    color: var(--text-primary);
+  }
+
+  .card-subtitle {
+    font-size: 12px;
+    color: var(--text-tertiary);
+    margin-top: 2px;
+  }
+
+  /* ===== Form Elements ===== */
+  .form-grid {
+    display: grid;
+    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
+    gap: 14px;
+  }
+
+  .form-grid-2 {
+    display: grid;
+    grid-template-columns: 1fr 1fr;
+    gap: 14px;
+  }
+
+  .form-grid-3 {
+    display: grid;
+    grid-template-columns: 1fr 1fr 1fr;
+    gap: 14px;
+  }
+
+  .form-group {
+    display: flex;
+    flex-direction: column;
+    gap: 5px;
+  }
+
+  .form-group.full {
+    grid-column: 1 / -1;
+  }
+
+  .form-label {
+    font-size: 12px;
+    font-weight: 600;
+    color: var(--text-secondary);
+    text-transform: uppercase;
+    letter-spacing: 0.03em;
+  }
+
+  .form-input, .form-select, .form-textarea {
+    padding: 8px 12px;
+    border: 1px solid var(--border);
+    border-radius: var(--radius-sm);
+    font-size: 13px;
+    color: var(--text-primary);
+    background: var(--bg-secondary);
+    font-family: var(--font-sans);
+    transition: border-color 0.15s, box-shadow 0.15s;
+    outline: none;
+  }
+
+  .form-input:focus, .form-select:focus, .form-textarea:focus {
+    border-color: var(--accent);
+    box-shadow: 0 0 0 3px var(--accent-light);
+  }
+
+  .form-input.mono {
+    font-family: var(--font-mono);
+    font-size: 12px;
+  }
+
+  .form-textarea {
+    resize: vertical;
+    min-height: 120px;
+    font-family: var(--font-mono);
+    font-size: 12px;
+    line-height: 1.6;
+  }
+
+  .form-select {
+    cursor: pointer;
+    appearance: none;
+    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%238b909e' viewBox='0 0 16 16'%3E%3Cpath d='M8 11L3 6h10z'/%3E%3C/svg%3E");
+    background-repeat: no-repeat;
+    background-position: right 10px center;
+    padding-right: 30px;
+  }
+
+  .toggle-row {
+    display: flex;
+    align-items: center;
+    gap: 8px;
+    padding: 6px 0;
+  }
+
+  .toggle {
+    position: relative;
+    width: 40px;
+    height: 22px;
+    flex-shrink: 0;
+  }
+
+  .toggle input {
+    opacity: 0;
+    width: 0;
+    height: 0;
+  }
+
+  .toggle-slider {
+    position: absolute;
+    cursor: pointer;
+    top: 0; left: 0; right: 0; bottom: 0;
+    background: var(--border);
+    border-radius: 22px;
+    transition: 0.2s;
+  }
+
+  .toggle-slider::before {
+    content: "";
+    position: absolute;
+    height: 16px;
+    width: 16px;
+    left: 3px;
+    bottom: 3px;
+    background: white;
+    border-radius: 50%;
+    transition: 0.2s;
+  }
+
+  .toggle input:checked + .toggle-slider {
+    background: var(--accent);
+  }
+
+  .toggle input:checked + .toggle-slider::before {
+    transform: translateX(18px);
+  }
+
+  .toggle-label {
+    font-size: 13px;
+    font-weight: 500;
+    color: var(--text-secondary);
+  }
+
+  /* ===== Message Log ===== */
+  .message-log {
+    background: #1e1e2e;
+    border-radius: var(--radius-md);
+    padding: 16px;
+    max-height: 400px;
+    overflow-y: auto;
+    font-family: var(--font-mono);
+    font-size: 12px;
+    line-height: 1.7;
+    color: #cdd6f4;
+  }
+
+  .msg-entry {
+    padding: 4px 0;
+    border-bottom: 1px solid rgba(255,255,255,0.04);
+    display: flex;
+    gap: 8px;
+  }
+
+  .msg-time {
+    color: #6c7086;
+    flex-shrink: 0;
+  }
+
+  .msg-direction {
+    flex-shrink: 0;
+    font-weight: 700;
+    width: 30px;
+  }
+
+  .msg-direction.pub { color: #89b4fa; }
+  .msg-direction.sub { color: #a6e3a1; }
+
+  .msg-topic {
+    color: #f9e2af;
+    flex-shrink: 0;
+    max-width: 200px;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+  }
+
+  .msg-payload {
+    color: #cdd6f4;
+    flex: 1;
+    word-break: break-all;
+  }
+
+  .msg-meta {
+    color: #6c7086;
+    font-size: 11px;
+    flex-shrink: 0;
+  }
+
+  .empty-state {
+    text-align: center;
+    padding: 40px 20px;
+    color: var(--text-muted);
+  }
+
+  .empty-state-icon {
+    font-size: 48px;
+    margin-bottom: 12px;
+    opacity: 0.5;
+  }
+
+  .empty-state-text {
+    font-size: 14px;
+    font-weight: 500;
+  }
+
+  /* ===== Topic List ===== */
+  .topic-list {
+    display: flex;
+    flex-direction: column;
+    gap: 6px;
+  }
+
+  .topic-item {
+    display: flex;
+    align-items: center;
+    gap: 10px;
+    padding: 10px 14px;
+    background: var(--bg-tertiary);
+    border-radius: var(--radius-sm);
+    transition: all 0.15s;
+    border: 1px solid transparent;
+  }
+
+  .topic-item:hover {
+    background: var(--bg-hover);
+  }
+
+  .topic-item.subscribed {
+    border-color: var(--success);
+    background: var(--success-light);
+  }
+
+  .topic-item-text {
+    flex: 1;
+    font-family: var(--font-mono);
+    font-size: 12px;
+    color: var(--text-primary);
+    min-width: 0;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+  }
+
+  .topic-item-qos {
+    font-size: 11px;
+    font-weight: 600;
+    padding: 2px 8px;
+    border-radius: 10px;
+    background: var(--bg-hover);
+    color: var(--text-secondary);
+    flex-shrink: 0;
+  }
+
+  .topic-item.subscribed .topic-item-qos {
+    background: var(--success);
+    color: #fff;
+  }
+
+  .badge {
+    display: inline-flex;
+    align-items: center;
+    padding: 2px 8px;
+    border-radius: 10px;
+    font-size: 11px;
+    font-weight: 600;
+  }
+
+  .badge-success { background: var(--success-light); color: var(--success); }
+  .badge-warning { background: var(--warning-light); color: var(--warning); }
+  .badge-danger { background: var(--danger-light); color: var(--danger); }
+  .badge-info { background: var(--info-light); color: var(--info); }
+
+  /* ===== Stats ===== */
+  .stats-grid {
+    display: grid;
+    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
+    gap: 12px;
+  }
+
+  .stat-card {
+    background: var(--bg-secondary);
+    border: 1px solid var(--border);
+    border-radius: var(--radius-lg);
+    padding: 16px 20px;
+    box-shadow: var(--shadow-sm);
+  }
+
+  .stat-label {
+    font-size: 11px;
+    font-weight: 600;
+    color: var(--text-tertiary);
+    text-transform: uppercase;
+    letter-spacing: 0.04em;
+  }
+
+  .stat-value {
+    font-size: 28px;
+    font-weight: 700;
+    color: var(--text-primary);
+    margin-top: 4px;
+    letter-spacing: -0.02em;
+  }
+
+  .stat-value.accent { color: var(--accent); }
+
+  /* ===== Modal ===== */
+  .modal-overlay {
+    position: fixed;
+    inset: 0;
+    background: rgba(0,0,0,0.35);
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    z-index: 100;
+    animation: fadeIn 0.15s ease;
+  }
+
+  @keyframes fadeIn {
+    from { opacity: 0; }
+    to { opacity: 1; }
+  }
+
+  .modal {
+    background: var(--bg-secondary);
+    border-radius: var(--radius-xl);
+    padding: 24px;
+    width: 520px;
+    max-width: 90vw;
+    max-height: 85vh;
+    overflow-y: auto;
+    box-shadow: var(--shadow-lg);
+    animation: slideUp 0.2s ease;
+  }
+
+  @keyframes slideUp {
+    from { transform: translateY(12px); opacity: 0; }
+    to { transform: translateY(0); opacity: 1; }
+  }
+
+  .modal-title {
+    font-size: 16px;
+    font-weight: 700;
+    margin-bottom: 20px;
+    color: var(--text-primary);
+  }
+
+  .modal-actions {
+    display: flex;
+    justify-content: flex-end;
+    gap: 8px;
+    margin-top: 20px;
+  }
+
+  /* ===== Toolbar ===== */
+  .toolbar {
+    display: flex;
+    align-items: center;
+    gap: 8px;
+    flex-wrap: wrap;
+  }
+
+  .flex-spacer { flex: 1; }
+
+  /* ===== Responsive ===== */
+  @media (max-width: 768px) {
+    .sidebar {
+      position: fixed;
+      left: -100%;
+      top: 0;
+      bottom: 0;
+      transition: left 0.25s;
+    }
+    .sidebar.open { left: 0; }
+    .form-grid, .form-grid-2, .form-grid-3 {
+      grid-template-columns: 1fr;
+    }
+    .stats-grid {
+      grid-template-columns: 1fr 1fr;
+    }
+    .main-content { padding: 14px; }
+  }
+
+  /* ===== Toast ===== */
+  .toast-container {
+    position: fixed;
+    top: 20px;
+    right: 20px;
+    z-index: 200;
+    display: flex;
+    flex-direction: column;
+    gap: 8px;
+  }
+
+  .toast {
+    padding: 12px 20px;
+    border-radius: var(--radius-md);
+    font-size: 13px;
+    font-weight: 500;
+    box-shadow: var(--shadow-lg);
+    animation: slideInRight 0.25s ease;
+    min-width: 250px;
+    display: flex;
+    align-items: center;
+    gap: 8px;
+  }
+
+  @keyframes slideInRight {
+    from { transform: translateX(100%); opacity: 0; }
+    to { transform: translateX(0); opacity: 1; }
+  }
+
+  .toast-success { background: var(--success); color: #fff; }
+  .toast-error { background: var(--danger); color: #fff; }
+  .toast-info { background: var(--info); color: #fff; }
+  .toast-warning { background: var(--warning); color: #fff; }
+
+  /* ===== Section divider ===== */
+  .section-divider {
+    border: none;
+    border-top: 1px solid var(--border-light);
+    margin: 16px 0;
+  }
+
+  /* ===== Quick actions row ===== */
+  .quick-actions {
+    display: flex;
+    gap: 8px;
+    flex-wrap: wrap;
+  }
+</style>
+</head>
+<body>
+
+<!-- Sidebar -->
+<aside class="sidebar" id="sidebar">
+  <div class="sidebar-header">
+    <div class="sidebar-logo">F</div>
+    <div>
+      <div class="sidebar-title">Frost MQTT Client</div>
+      <div class="sidebar-subtitle">多服务器管理客户端</div>
+    </div>
+  </div>
+
+  <div class="server-list" id="serverList">
+    <!-- 动态渲染 -->
+  </div>
+
+  <div class="sidebar-footer">
+    <button class="btn btn-primary btn-full" onclick="openServerModal()">
+      + 添加服务器
+    </button>
+  </div>
+</aside>
+
+<!-- Main Content -->
+<main class="main">
+  <div class="main-header" id="mainHeader">
+    <div class="tab-btn active" data-tab="dashboard">
+      <span class="tab-icon">&#9681;</span> 仪表盘
+    </div>
+    <div class="tab-btn" data-tab="subscribe">
+      <span class="tab-icon">&#9776;</span> 主题订阅
+    </div>
+    <div class="tab-btn" data-tab="publish">
+      <span class="tab-icon">&#9654;</span> 消息发布
+    </div>
+    <div class="tab-btn" data-tab="messages">
+      <span class="tab-icon">&#9776;</span> 消息监控
+    </div>
+  </div>
+
+  <div class="main-content" id="mainContent">
+    <!-- Dashboard Tab -->
+    <div class="tab-panel active" id="panel-dashboard">
+      <div class="empty-state" id="dashboardEmpty">
+        <div class="empty-state-icon">&#9881;</div>
+        <div class="empty-state-text">请先在左侧添加并选择一个 MQTT 服务器</div>
+      </div>
+      <div id="dashboardContent" style="display:none;"></div>
+    </div>
+
+    <!-- Subscribe Tab -->
+    <div class="tab-panel" id="panel-subscribe">
+      <div class="empty-state" id="subscribeEmpty">
+        <div class="empty-state-icon">&#9776;</div>
+        <div class="empty-state-text">请先在左侧选择一个 MQTT 服务器</div>
+      </div>
+      <div id="subscribeContent" style="display:none;">
+        <div class="card">
+          <div class="card-header">
+            <div>
+              <div class="card-title">添加订阅主题</div>
+              <div class="card-subtitle">配置需要订阅的 MQTT 主题</div>
+            </div>
+          </div>
+          <div class="form-grid">
+            <div class="form-group">
+              <label class="form-label">主题 (Topic)</label>
+              <input class="form-input mono" id="subscribeTopic" placeholder="例如: sensor/+/temperature" onkeydown="if(event.key==='Enter')addTopic()">
+            </div>
+            <div class="form-group">
+              <label class="form-label">QoS</label>
+              <select class="form-select" id="subscribeQos">
+                <option value="0">QoS 0 - 最多一次</option>
+                <option value="1">QoS 1 - 至少一次</option>
+                <option value="2" selected>QoS 2 - 恰好一次</option>
+              </select>
+            </div>
+            <div class="form-group" style="justify-content:flex-end;">
+              <button class="btn btn-primary" onclick="addTopic()">+ 添加订阅</button>
+            </div>
+          </div>
+        </div>
+        <div class="card">
+          <div class="card-header">
+            <div class="card-title">已订阅主题列表</div>
+            <button class="btn btn-sm btn-outline" onclick="subscribeAllTopics()">全部订阅</button>
+          </div>
+          <div class="topic-list" id="topicList">
+            <div class="empty-state" style="padding:20px;">
+              <div class="empty-state-text" style="font-size:13px;">暂无订阅主题，请在上方添加</div>
+            </div>
+          </div>
+        </div>
+      </div>
+    </div>
+
+    <!-- Publish Tab -->
+    <div class="tab-panel" id="panel-publish">
+      <div class="empty-state" id="publishEmpty">
+        <div class="empty-state-icon">&#9654;</div>
+        <div class="empty-state-text">请先在左侧选择一个 MQTT 服务器</div>
+      </div>
+      <div id="publishContent" style="display:none;">
+        <div class="card">
+          <div class="card-header">
+            <div>
+              <div class="card-title">发布消息</div>
+              <div class="card-subtitle">向指定主题发送 MQTT 消息</div>
+            </div>
+          </div>
+          <div class="form-grid">
+            <div class="form-group">
+              <label class="form-label">目标主题 (Topic)</label>
+              <input class="form-input mono" id="publishTopic" placeholder="例如: sensor/device01/temperature">
+            </div>
+            <div class="form-group">
+              <label class="form-label">QoS</label>
+              <select class="form-select" id="publishQos">
+                <option value="0">QoS 0 - 最多一次</option>
+                <option value="1" selected>QoS 1 - 至少一次</option>
+                <option value="2">QoS 2 - 恰好一次</option>
+              </select>
+            </div>
+            <div class="form-group" style="justify-content:flex-end;">
+              <div class="toggle-row">
+                <label class="toggle">
+                  <input type="checkbox" id="publishRetain">
+                  <span class="toggle-slider"></span>
+                </label>
+                <span class="toggle-label">保留消息 (Retain)</span>
+              </div>
+            </div>
+          </div>
+          <div class="form-group" style="margin-top:14px;">
+            <label class="form-label">消息内容 (Payload)</label>
+            <textarea class="form-textarea" id="publishPayload" placeholder='{"temperature": 25.6, "humidity": 68.3}'></textarea>
+          </div>
+          <div style="margin-top:14px;display:flex;gap:8px;">
+            <button class="btn btn-primary" onclick="publishMessage()">&#9654; 发布消息</button>
+            <button class="btn btn-outline btn-sm" onclick="formatJson()">格式化 JSON</button>
+          </div>
+        </div>
+        <div class="card">
+          <div class="card-header">
+            <div class="card-title">发布历史</div>
+            <button class="btn btn-sm btn-outline" onclick="clearPublishHistory()">清空</button>
+          </div>
+          <div class="message-log" id="publishHistory" style="max-height:250px;">
+            <div style="color:#6c7086;text-align:center;padding:20px;">暂无发布记录</div>
+          </div>
+        </div>
+      </div>
+    </div>
+
+    <!-- Messages Tab -->
+    <div class="tab-panel" id="panel-messages">
+      <div class="empty-state" id="messagesEmpty">
+        <div class="empty-state-icon">&#9776;</div>
+        <div class="empty-state-text">请先在左侧选择一个 MQTT 服务器</div>
+      </div>
+      <div id="messagesContent" style="display:none;">
+        <div class="card">
+          <div class="card-header">
+            <div>
+              <div class="card-title">消息监控</div>
+              <div class="card-subtitle">实时查看接收和发送的 MQTT 消息</div>
+            </div>
+            <div class="toolbar">
+              <input class="form-input" style="width:180px;font-size:12px;" placeholder="过滤主题..." id="msgFilter" oninput="renderMessages()">
+              <button class="btn btn-sm btn-outline" onclick="clearMessages()">清空</button>
+              <button class="btn btn-sm btn-outline" id="autoScrollBtn" onclick="toggleAutoScroll()">自动滚动: 开</button>
+            </div>
+          </div>
+          <div class="message-log" id="messageLog" style="max-height:500px;">
+            <div style="color:#6c7086;text-align:center;padding:20px;">等待消息...</div>
+          </div>
+        </div>
+      </div>
+    </div>
+  </div>
+</main>
+
+<!-- Server Modal -->
+<div class="modal-overlay" id="serverModal" style="display:none;" onclick="if(event.target===this)closeServerModal()">
+  <div class="modal">
+    <div class="modal-title" id="serverModalTitle">添加 MQTT 服务器</div>
+    <div class="form-grid">
+      <div class="form-group">
+        <label class="form-label">服务器名称</label>
+        <input class="form-input" id="srvName" placeholder="例如: 本地开发服务器">
+      </div>
+      <div class="form-group">
+        <label class="form-label">主机地址 (Host)</label>
+        <input class="form-input mono" id="srvHost" placeholder="例如: broker.emqx.io">
+      </div>
+      <div class="form-group">
+        <label class="form-label">端口 (Port)</label>
+        <input class="form-input mono" id="srvPort" placeholder="1883" type="number">
+      </div>
+      <div class="form-group">
+        <label class="form-label">客户端 ID</label>
+        <input class="form-input mono" id="srvClientId" placeholder="自动生成">
+      </div>
+      <div class="form-group">
+        <label class="form-label">用户名</label>
+        <input class="form-input" id="srvUsername" placeholder="可选">
+      </div>
+      <div class="form-group">
+        <label class="form-label">密码</label>
+        <input class="form-input" id="srvPassword" type="password" placeholder="可选">
+      </div>
+      <div class="form-group">
+        <label class="form-label">协议</label>
+        <select class="form-select" id="srvProtocol">
+          <option value="mqtt">mqtt:// (默认)</option>
+          <option value="mqtts">mqtts:// (TLS)</option>
+          <option value="ws">ws:// (WebSocket)</option>
+          <option value="wss">wss:// (WebSocket TLS)</option>
+        </select>
+      </div>
+      <div class="form-group">
+        <label class="form-label">Keep Alive (秒)</label>
+        <input class="form-input" id="srvKeepAlive" placeholder="60" type="number" value="60">
+      </div>
+      <div class="form-group full">
+        <div class="toggle-row">
+          <label class="toggle">
+            <input type="checkbox" id="srvCleanSession">
+            <span class="toggle-slider"></span>
+          </label>
+          <span class="toggle-label">Clean Session</span>
+        </div>
+      </div>
+    </div>
+    <div class="modal-actions">
+      <button class="btn btn-outline" onclick="closeServerModal()">取消</button>
+      <button class="btn btn-primary" id="srvSaveBtn" onclick="saveServer()">保存</button>
+    </div>
+  </div>
+</div>
+
+<!-- Toast Container -->
+<div class="toast-container" id="toastContainer"></div>
+
+<script>
+// ==================== 数据模型 ====================
+const DEFAULT_SERVERS = [
+  {
+    id: 'srv_001',
+    name: 'EMQX 公共测试',
+    host: 'broker.emqx.io',
+    port: 1883,
+    protocol: 'mqtt',
+    clientId: 'frost_client_' + Math.random().toString(36).slice(2, 8),
+    username: '',
+    password: '',
+    keepAlive: 60,
+    cleanSession: true,
+    status: 'disconnected', // disconnected | connecting | connected | error
+    topics: [
+      { topic: 'sensor/+/temperature', qos: 1, subscribed: false },
+      { topic: 'device/status', qos: 2, subscribed: false },
+    ],
+    messages: [],
+    publishHistory: []
+  },
+  {
+    id: 'srv_002',
+    name: '本地 Mosquitto',
+    host: 'localhost',
+    port: 1883,
+    protocol: 'mqtt',
+    clientId: 'frost_local_' + Math.random().toString(36).slice(2, 8),
+    username: '',
+    password: '',
+    keepAlive: 60,
+    cleanSession: true,
+    status: 'disconnected',
+    topics: [
+      { topic: 'home/+/light', qos: 1, subscribed: false },
+      { topic: 'home/alarm', qos: 2, subscribed: false },
+    ],
+    messages: [],
+    publishHistory: []
+  }
+];
+
+let servers = JSON.parse(localStorage.getItem('frost_mqtt_servers') || 'null') || DEFAULT_SERVERS;
+let activeServerId = localStorage.getItem('frost_mqtt_active_server') || (servers.length > 0 ? servers[0].id : null);
+let editingServerId = null;
+let autoScroll = true;
+
+// ==================== 工具函数 ====================
+function saveData() {
+  localStorage.setItem('frost_mqtt_servers', JSON.stringify(servers));
+  localStorage.setItem('frost_mqtt_active_server', activeServerId || '');
+}
+
+function getActiveServer() {
+  return servers.find(s => s.id === activeServerId);
+}
+
+function getServer(id) {
+  return servers.find(s => s.id === id);
+}
+
+function generateId() {
+  return 'srv_' + Date.now() + '_' + Math.random().toString(36).slice(2, 6);
+}
+
+function now() {
+  const d = new Date();
+  return d.toLocaleTimeString('zh-CN', { hour12: false }) + '.' + String(d.getMilliseconds()).padStart(3, '0');
+}
+
+function showToast(msg, type = 'info') {
+  const container = document.getElementById('toastContainer');
+  const toast = document.createElement('div');
+  toast.className = 'toast toast-' + type;
+  toast.textContent = msg;
+  container.appendChild(toast);
+  setTimeout(() => {
+    toast.style.opacity = '0';
+    toast.style.transition = 'opacity 0.3s';
+    setTimeout(() => toast.remove(), 300);
+  }, 2500);
+}
+
+// ==================== 服务器管理 ====================
+function openServerModal(serverId = null) {
+  editingServerId = serverId;
+  const modal = document.getElementById('serverModal');
+  const title = document.getElementById('serverModalTitle');
+  const saveBtn = document.getElementById('srvSaveBtn');
+
+  if (serverId) {
+    const srv = getServer(serverId);
+    if (!srv) return;
+    title.textContent = '编辑 MQTT 服务器';
+    saveBtn.textContent = '更新';
+    document.getElementById('srvName').value = srv.name;
+    document.getElementById('srvHost').value = srv.host;
+    document.getElementById('srvPort').value = srv.port;
+    document.getElementById('srvProtocol').value = srv.protocol;
+    document.getElementById('srvClientId').value = srv.clientId;
+    document.getElementById('srvUsername').value = srv.username;
+    document.getElementById('srvPassword').value = srv.password;
+    document.getElementById('srvKeepAlive').value = srv.keepAlive;
+    document.getElementById('srvCleanSession').checked = srv.cleanSession;
+  } else {
+    title.textContent = '添加 MQTT 服务器';
+    saveBtn.textContent = '保存';
+    document.getElementById('srvName').value = '';
+    document.getElementById('srvHost').value = '';
+    document.getElementById('srvPort').value = '1883';
+    document.getElementById('srvProtocol').value = 'mqtt';
+    document.getElementById('srvClientId').value = 'frost_' + Math.random().toString(36).slice(2, 10);
+    document.getElementById('srvUsername').value = '';
+    document.getElementById('srvPassword').value = '';
+    document.getElementById('srvKeepAlive').value = '60';
+    document.getElementById('srvCleanSession').checked = true;
+  }
+
+  modal.style.display = 'flex';
+}
+
+function closeServerModal() {
+  document.getElementById('serverModal').style.display = 'none';
+  editingServerId = null;
+}
+
+function saveServer() {
+  const name = document.getElementById('srvName').value.trim();
+  const host = document.getElementById('srvHost').value.trim();
+  const port = parseInt(document.getElementById('srvPort').value) || 1883;
+  const protocol = document.getElementById('srvProtocol').value;
+  const clientId = document.getElementById('srvClientId').value.trim();
+  const username = document.getElementById('srvUsername').value.trim();
+  const password = document.getElementById('srvPassword').value;
+  const keepAlive = parseInt(document.getElementById('srvKeepAlive').value) || 60;
+  const cleanSession = document.getElementById('srvCleanSession').checked;
+
+  if (!name || !host) {
+    showToast('请填写服务器名称和主机地址', 'warning');
+    return;
+  }
+
+  if (editingServerId) {
+    const srv = getServer(editingServerId);
+    if (srv) {
+      srv.name = name;
+      srv.host = host;
+      srv.port = port;
+      srv.protocol = protocol;
+      srv.clientId = clientId;
+      srv.username = username;
+      srv.password = password;
+      srv.keepAlive = keepAlive;
+      srv.cleanSession = cleanSession;
+      showToast('服务器配置已更新', 'success');
+    }
+  } else {
+    servers.push({
+      id: generateId(),
+      name,
+      host,
+      port,
+      protocol,
+      clientId: clientId || 'frost_' + Math.random().toString(36).slice(2, 10),
+      username,
+      password,
+      keepAlive,
+      cleanSession,
+      status: 'disconnected',
+      topics: [],
+      messages: [],
+      publishHistory: []
+    });
+    showToast('服务器已添加', 'success');
+  }
+
+  closeServerModal();
+  saveData();
+  renderAll();
+}
+
+function deleteServer(serverId) {
+  if (!confirm('确定要删除此服务器配置吗？')) return;
+  servers = servers.filter(s => s.id !== serverId);
+  if (activeServerId === serverId) {
+    activeServerId = servers.length > 0 ? servers[0].id : null;
+  }
+  saveData();
+  renderAll();
+  showToast('服务器已删除', 'info');
+}
+
+function toggleConnection(serverId) {
+  const srv = getServer(serverId);
+  if (!srv) return;
+
+  if (srv.status === 'connected') {
+    // 模拟断开
+    srv.status = 'disconnected';
+    // 取消所有订阅状态
+    srv.topics.forEach(t => t.subscribed = false);
+    showToast(srv.name + ' 已断开连接', 'info');
+  } else if (srv.status === 'disconnected' || srv.status === 'error') {
+    // 模拟连接过程
+    srv.status = 'connecting';
+    renderAll();
+    setTimeout(() => {
+      srv.status = 'connected';
+      saveData();
+      renderAll();
+      showToast(srv.name + ' 连接成功', 'success');
+      // 自动订阅已配置的主题
+      srv.topics.forEach(t => { t.subscribed = true; });
+      saveData();
+      renderAll();
+    }, 800 + Math.random() * 600);
+    return;
+  } else {
+    return; // 连接中，不响应
+  }
+
+  saveData();
+  renderAll();
+}
+
+function selectServer(serverId) {
+  activeServerId = serverId;
+  saveData();
+  renderAll();
+}
+
+// ==================== 主题管理 ====================
+function addTopic() {
+  const srv = getActiveServer();
+  if (!srv) return;
+  const topicInput = document.getElementById('subscribeTopic');
+  const topic = topicInput.value.trim();
+  if (!topic) {
+    showToast('请输入主题名称', 'warning');
+    return;
+  }
+  const qos = parseInt(document.getElementById('subscribeQos').value);
+
+  if (srv.topics.find(t => t.topic === topic)) {
+    showToast('该主题已存在', 'warning');
+    return;
+  }
+
+  srv.topics.push({ topic, qos, subscribed: srv.status === 'connected' });
+  topicInput.value = '';
+  saveData();
+  renderAll();
+  showToast('主题已添加' + (srv.status === 'connected' ? '并已订阅' : ''), 'success');
+}
+
+function removeTopic(topic) {
+  const srv = getActiveServer();
+  if (!srv) return;
+  srv.topics = srv.topics.filter(t => t.topic !== topic);
+  saveData();
+  renderAll();
+  showToast('主题已移除', 'info');
+}
+
+function toggleTopicSubscription(topicStr) {
+  const srv = getActiveServer();
+  if (!srv) return;
+  if (srv.status !== 'connected') {
+    showToast('请先连接服务器', 'warning');
+    return;
+  }
+  const topic = srv.topics.find(t => t.topic === topicStr);
+  if (!topic) return;
+  topic.subscribed = !topic.subscribed;
+  saveData();
+  renderAll();
+  showToast(topic.subscribed ? '已订阅: ' + topicStr : '已取消订阅: ' + topicStr, 'info');
+}
+
+function subscribeAllTopics() {
+  const srv = getActiveServer();
+  if (!srv) return;
+  if (srv.status !== 'connected') {
+    showToast('请先连接服务器', 'warning');
+    return;
+  }
+  srv.topics.forEach(t => t.subscribed = true);
+  saveData();
+  renderAll();
+  showToast('已订阅全部主题', 'success');
+}
+
+// ==================== 消息发布 ====================
+function publishMessage() {
+  const srv = getActiveServer();
+  if (!srv) return;
+  if (srv.status !== 'connected') {
+    showToast('请先连接服务器', 'warning');
+    return;
+  }
+
+  const topic = document.getElementById('publishTopic').value.trim();
+  const payload = document.getElementById('publishPayload').value;
+  const qos = parseInt(document.getElementById('publishQos').value);
+  const retain = document.getElementById('publishRetain').checked;
+
+  if (!topic) {
+    showToast('请输入目标主题', 'warning');
+    return;
+  }
+
+  // 模拟发布
+  const pubEntry = {
+    time: now(),
+    topic,
+    payload,
+    qos,
+    retain,
+    direction: 'pub'
+  };
+
+  srv.publishHistory.unshift(pubEntry);
+  if (srv.publishHistory.length > 50) srv.publishHistory.pop();
+
+  // 同时添加到消息日志
+  srv.messages.unshift({
+    ...pubEntry,
+    id: 'msg_' + Date.now()
+  });
+  if (srv.messages.length > 200) srv.messages.pop();
+
+  saveData();
+  renderAll();
+  showToast('消息已发布到: ' + topic, 'success');
+
+  // 模拟收到回显消息
+  setTimeout(() => {
+    const srv2 = getServer(srv.id);
+    if (srv2 && srv2.status === 'connected') {
+      srv2.messages.unshift({
+        time: now(),
+        topic,
+        payload,
+        qos,
+        direction: 'sub',
+        id: 'msg_' + Date.now()
+      });
+      if (srv2.messages.length > 200) srv2.messages.pop();
+      saveData();
+      if (activeServerId === srv2.id) renderMessages();
+    }
+  }, 300 + Math.random() * 500);
+}
+
+function formatJson() {
+  const textarea = document.getElementById('publishPayload');
+  try {
+    const obj = JSON.parse(textarea.value);
+    textarea.value = JSON.stringify(obj, null, 2);
+    showToast('JSON 已格式化', 'info');
+  } catch (e) {
+    showToast('无效的 JSON 格式', 'warning');
+  }
+}
+
+function clearPublishHistory() {
+  const srv = getActiveServer();
+  if (!srv) return;
+  srv.publishHistory = [];
+  saveData();
+  renderAll();
+}
+
+// ==================== 消息监控 ====================
+function clearMessages() {
+  const srv = getActiveServer();
+  if (!srv) return;
+  srv.messages = [];
+  saveData();
+  renderAll();
+}
+
+function toggleAutoScroll() {
+  autoScroll = !autoScroll;
+  document.getElementById('autoScrollBtn').textContent = '自动滚动: ' + (autoScroll ? '开' : '关');
+}
+
+function renderMessages() {
+  const srv = getActiveServer();
+  const log = document.getElementById('messageLog');
+  const filter = (document.getElementById('msgFilter')?.value || '').trim().toLowerCase();
+
+  if (!srv || srv.messages.length === 0) {
+    log.innerHTML = '<div style="color:#6c7086;text-align:center;padding:20px;">等待消息...</div>';
+    return;
+  }
+
+  let filtered = srv.messages;
+  if (filter) {
+    filtered = srv.messages.filter(m => m.topic.toLowerCase().includes(filter));
+  }
+
+  log.innerHTML = filtered.map(m => `
+    <div class="msg-entry">
+      <span class="msg-time">${m.time}</span>
+      <span class="msg-direction ${m.direction}">${m.direction === 'pub' ? 'PUB' : 'SUB'}</span>
+      <span class="msg-topic" title="${m.topic}">${m.topic}</span>
+      <span class="msg-payload">${escapeHtml(m.payload.length > 100 ? m.payload.slice(0, 100) + '...' : m.payload)}</span>
+      <span class="msg-meta">QoS${m.qos}${m.retain ? ' R' : ''}</span>
+    </div>
+  `).join('');
+
+  if (filtered.length === 0) {
+    log.innerHTML = '<div style="color:#6c7086;text-align:center;padding:20px;">无匹配消息</div>';
+  }
+
+  if (autoScroll) {
+    log.scrollTop = 0;
+  }
+}
+
+function escapeHtml(str) {
+  const div = document.createElement('div');
+  div.textContent = str;
+  return div.innerHTML;
+}
+
+// ==================== 渲染 ====================
+function renderAll() {
+  renderServerList();
+  renderMainContent();
+  updateTabVisibility();
+}
+
+function renderServerList() {
+  const list = document.getElementById('serverList');
+  list.innerHTML = servers.map(srv => {
+    const activeClass = srv.id === activeServerId ? ' active' : '';
+    const statusLabel = {
+      'disconnected': '未连接',
+      'connecting': '连接中...',
+      'connected': '已连接',
+      'error': '连接失败'
+    }[srv.status] || '未知';
+
+    return `
+      <div class="server-item${activeClass}" onclick="selectServer('${srv.id}')">
+        <div class="server-item-header">
+          <span class="server-item-name" title="${srv.name}">${srv.name}</span>
+          <div class="server-item-actions">
+            <button class="icon-btn" title="编辑" onclick="event.stopPropagation();openServerModal('${srv.id}')">&#9998;</button>
+            <button class="icon-btn danger" title="删除" onclick="event.stopPropagation();deleteServer('${srv.id}')">&#10005;</button>
+          </div>
+        </div>
+        <div style="display:flex;align-items:center;gap:6px;margin-top:4px;">
+          <span class="status-dot ${srv.status}"></span>
+          <span class="server-item-url">${srv.protocol}://${srv.host}:${srv.port}</span>
+        </div>
+        <div style="display:flex;align-items:center;justify-content:space-between;margin-top:6px;">
+          <span style="font-size:11px;color:var(--text-muted);">${statusLabel}</span>
+          <button class="btn btn-xs ${srv.status === 'connected' ? 'btn-danger' : srv.status === 'connecting' ? 'btn-warning' : 'btn-success'}"
+            onclick="event.stopPropagation();toggleConnection('${srv.id}')"
+            ${srv.status === 'connecting' ? 'disabled' : ''}>
+            ${srv.status === 'connected' ? '断开' : srv.status === 'connecting' ? '...' : '连接'}
+          </button>
+        </div>
+      </div>
+    `;
+  }).join('');
+}
+
+function renderMainContent() {
+  const srv = getActiveServer();
+  const isConnected = srv && srv.status === 'connected';
+
+  // 各面板的空状态/内容切换
+  ['dashboard', 'subscribe', 'publish', 'messages'].forEach(panel => {
+    const emptyEl = document.getElementById(panel + 'Empty');
+    const contentEl = document.getElementById(panel + 'Content');
+    if (!emptyEl || !contentEl) return;
+    if (srv) {
+      emptyEl.style.display = 'none';
+      contentEl.style.display = 'block';
+    } else {
+      emptyEl.style.display = 'block';
+      contentEl.style.display = 'none';
+    }
+  });
+
+  if (!srv) return;
+
+  // 仪表盘
+  renderDashboard(srv);
+
+  // 主题列表
+  renderTopicList(srv);
+
+  // 发布历史
+  renderPublishHistory(srv);
+
+  // 消息监控
+  renderMessages();
+}
+
+function renderDashboard(srv) {
+  const container = document.getElementById('dashboardContent');
+  const connectedCount = servers.filter(s => s.status === 'connected').length;
+  const totalTopics = servers.reduce((sum, s) => sum + s.topics.length, 0);
+  const subscribedTopics = servers.reduce((sum, s) => sum + s.topics.filter(t => t.subscribed).length, 0);
+  const totalMessages = servers.reduce((sum, s) => sum + s.messages.length, 0);
+
+  container.innerHTML = `
+    <div class="stats-grid">
+      <div class="stat-card">
+        <div class="stat-label">服务器总数</div>
+        <div class="stat-value">${servers.length}</div>
+      </div>
+      <div class="stat-card">
+        <div class="stat-label">已连接</div>
+        <div class="stat-value accent">${connectedCount}</div>
+      </div>
+      <div class="stat-card">
+        <div class="stat-label">已订阅主题</div>
+        <div class="stat-value">${subscribedTopics}<span style="font-size:14px;color:var(--text-tertiary);">/${totalTopics}</span></div>
+      </div>
+      <div class="stat-card">
+        <div class="stat-label">消息总数</div>
+        <div class="stat-value">${totalMessages}</div>
+      </div>
+    </div>
+
+    <div class="card" style="margin-top:16px;">
+      <div class="card-header">
+        <div>
+          <div class="card-title">当前服务器: ${srv.name}</div>
+          <div class="card-subtitle">${srv.protocol}://${srv.host}:${srv.port} &nbsp;|&nbsp; 客户端: ${srv.clientId}</div>
+        </div>
+        <span class="badge ${srv.status === 'connected' ? 'badge-success' : srv.status === 'connecting' ? 'badge-warning' : 'badge-danger'}">
+          ${srv.status === 'connected' ? '已连接' : srv.status === 'connecting' ? '连接中...' : '未连接'}
+        </span>
+      </div>
+      <div class="quick-actions">
+        <button class="btn btn-sm ${srv.status === 'connected' ? 'btn-danger' : 'btn-success'}" onclick="toggleConnection('${srv.id}')">
+          ${srv.status === 'connected' ? '断开连接' : '连接服务器'}
+        </button>
+        <button class="btn btn-sm btn-outline" onclick="openServerModal('${srv.id}')">编辑配置</button>
+        <button class="btn btn-sm btn-outline" onclick="switchTab('subscribe')">管理订阅</button>
+        <button class="btn btn-sm btn-outline" onclick="switchTab('publish')">发布消息</button>
+        <button class="btn btn-sm btn-outline" onclick="switchTab('messages')">查看消息</button>
+      </div>
+    </div>
+
+    <div class="card">
+      <div class="card-header">
+        <div class="card-title">所有服务器状态</div>
+      </div>
+      <div style="display:flex;flex-direction:column;gap:8px;">
+        ${servers.map(s => `
+          <div style="display:flex;align-items:center;gap:10px;padding:8px 12px;background:var(--bg-tertiary);border-radius:var(--radius-sm);">
+            <span class="status-dot ${s.status}"></span>
+            <span style="flex:1;font-size:13px;font-weight:500;">${s.name}</span>
+            <span style="font-family:var(--font-mono);font-size:11px;color:var(--text-tertiary);">${s.protocol}://${s.host}:${s.port}</span>
+            <span class="badge badge-${s.status === 'connected' ? 'success' : s.status === 'connecting' ? 'warning' : 'info'}">
+              ${s.status === 'connected' ? '已连接' : s.status === 'connecting' ? '连接中...' : '未连接'}
+            </span>
+            <button class="btn btn-xs ${s.status === 'connected' ? 'btn-danger' : 'btn-success'}" onclick="toggleConnection('${s.id}')">
+              ${s.status === 'connected' ? '断开' : s.status === 'connecting' ? '...' : '连接'}
+            </button>
+          </div>
+        `).join('')}
+      </div>
+    </div>
+  `;
+}
+
+function renderTopicList(srv) {
+  const container = document.getElementById('topicList');
+  if (!srv) return;
+
+  if (srv.topics.length === 0) {
+    container.innerHTML = '<div class="empty-state" style="padding:20px;"><div class="empty-state-text" style="font-size:13px;">暂无订阅主题，请在上方添加</div></div>';
+    return;
+  }
+
+  container.innerHTML = srv.topics.map(t => `
+    <div class="topic-item ${t.subscribed ? 'subscribed' : ''}">
+      <span class="topic-item-text" title="${t.topic}">${t.topic}</span>
+      <span class="topic-item-qos">QoS ${t.qos}</span>
+      <button class="btn btn-xs ${t.subscribed ? 'btn-danger' : 'btn-success'}"
+        onclick="toggleTopicSubscription('${t.topic}')">
+        ${t.subscribed ? '取消订阅' : '订阅'}
+      </button>
+      <button class="icon-btn danger" title="删除" onclick="removeTopic('${t.topic}')">&#10005;</button>
+    </div>
+  `).join('');
+}
+
+function renderPublishHistory(srv) {
+  const container = document.getElementById('publishHistory');
+  if (!srv) return;
+
+  if (srv.publishHistory.length === 0) {
+    container.innerHTML = '<div style="color:#6c7086;text-align:center;padding:20px;">暂无发布记录</div>';
+    return;
+  }
+
+  container.innerHTML = srv.publishHistory.map(m => `
+    <div class="msg-entry">
+      <span class="msg-time">${m.time}</span>
+      <span class="msg-direction pub">PUB</span>
+      <span class="msg-topic" title="${m.topic}">${m.topic}</span>
+      <span class="msg-payload">${escapeHtml(m.payload.length > 80 ? m.payload.slice(0, 80) + '...' : m.payload)}</span>
+      <span class="msg-meta">QoS${m.qos}${m.retain ? ' R' : ''}</span>
+    </div>
+  `).join('');
+}
+
+function updateTabVisibility() {
+  const srv = getActiveServer();
+  const header = document.getElementById('mainHeader');
+  // 无服务器时，tab 仍可见但内容显示空状态
+  // 不做额外处理
+}
+
+// ==================== Tab 切换 ====================
+function switchTab(tabName) {
+  document.querySelectorAll('.tab-btn').forEach(b => b.classList.remove('active'));
+  document.querySelectorAll('.tab-panel').forEach(p => p.classList.remove('active'));
+
+  const btn = document.querySelector(`.tab-btn[data-tab="${tabName}"]`);
+  const panel = document.getElementById('panel-' + tabName);
+  if (btn) btn.classList.add('active');
+  if (panel) panel.classList.add('active');
+
+  if (tabName === 'messages') {
+    setTimeout(() => {
+      const log = document.getElementById('messageLog');
+      if (log && autoScroll) log.scrollTop = 0;
+    }, 50);
+  }
+}
+
+// ==================== 事件绑定 ====================
+document.addEventListener('DOMContentLoaded', () => {
+  renderAll();
+
+  // Tab 切换
+  document.querySelectorAll('.tab-btn').forEach(btn => {
+    btn.addEventListener('click', () => {
+      switchTab(btn.dataset.tab);
+    });
+  });
+});
+
+// ==================== 模拟消息 ====================
+// 为已连接的服务器模拟接收消息
+setInterval(() => {
+  servers.forEach(srv => {
+    if (srv.status === 'connected' && srv.topics.length > 0) {
+      const subscribedTopics = srv.topics.filter(t => t.subscribed);
+      if (subscribedTopics.length > 0 && Math.random() > 0.7) {
+        const t = subscribedTopics[Math.floor(Math.random() * subscribedTopics.length)];
+        const actualTopic = t.topic.replace('+', 'device' + Math.floor(Math.random() * 10));
+        const temp = (20 + Math.random() * 15).toFixed(1);
+        const hum = (40 + Math.random() * 40).toFixed(1);
+        srv.messages.unshift({
+          time: now(),
+          topic: actualTopic,
+          payload: JSON.stringify({ temperature: parseFloat(temp), humidity: parseFloat(hum), timestamp: Date.now() }),
+          qos: t.qos,
+          direction: 'sub',
+          id: 'msg_' + Date.now()
+        });
+        if (srv.messages.length > 200) srv.messages.pop();
+        saveData();
+        if (activeServerId === srv.id) {
+          renderMessages();
+        }
+      }
+    }
+  });
+}, 3000);
+</script>
+
+</body>
+</html>
\ No newline at end of file
