diff --git a/web/App.vue b/web/App.vue
index caf0d74..81b6a40 100644
--- a/web/App.vue
+++ b/web/App.vue
@@ -100,8 +100,24 @@ const busyAct = ref(false)
 const historyOpen = ref(false)
 const askRestart = ref(false)
 
+/**
+ * 撤回/重做各自的冷却：窗内的连点算一次。手抖不该多退一步；顺带避开
+ * 重做的备份名同秒覆盖（备份名精确到秒，窗比一秒宽就撞不上）。
+ * 两个方向分开冷却，撤回错了马上重做这条路不受影响。
+ */
+const HISTORY_COOLDOWN_MS = 2_500
+const cooling = ref({ undo: false, redo: false })
+
+function coolDown(kind: 'undo' | 'redo') {
+  cooling.value = { ...cooling.value, [kind]: true }
+  window.setTimeout(() => {
+    cooling.value = { ...cooling.value, [kind]: false }
+  }, HISTORY_COOLDOWN_MS)
+}
+
 async function undo() {
-  if (busyAct.value) return
+  if (busyAct.value || cooling.value.undo) return
+  coolDown('undo')
   busyAct.value = true
   try {
     const result = await api.undoConfig()
@@ -115,7 +131,8 @@ async function undo() {
 }
 
 async function redo() {
-  if (busyAct.value) return
+  if (busyAct.value || cooling.value.redo) return
+  coolDown('redo')
   busyAct.value = true
   try {
     const result = await api.redoConfig()
@@ -239,7 +256,7 @@ const current = computed(() => NAV.find((n) => n.key === active.value))
           type="button"
           class="act"
           title="撤回"
-          :disabled="busyAct || !snapshot || history.backups.length === 0"
+          :disabled="busyAct || cooling.undo || !snapshot || history.backups.length === 0"
           @click="undo"
         >
           <IconUndo />
@@ -248,7 +265,7 @@ const current = computed(() => NAV.find((n) => n.key === active.value))
           type="button"
           class="act"
           title="重做"
-          :disabled="busyAct || !snapshot || history.redo === 0"
+          :disabled="busyAct || cooling.redo || !snapshot || history.redo === 0"
           @click="redo"
         >
           <IconRedo />
@@ -411,14 +428,18 @@ const current = computed(() => NAV.find((n) => n.key === active.value))
 
 /* ── 侧栏 ───────────────────────────────────── */
 /*
- * 钉在视口里。不加 sticky 的话它会被网格行撑到和主区一样高，页面一长，
- * 导航就跟着滚出屏幕外，而它是全局导航，任何时候都该够得着。
+ * 钉在视口里。用 fixed 而不是 sticky：sticky 元素的位置跟着 scrollTop 走，
+ * 而滚动到底时 scrollTop = scrollHeight - clientHeight，在 Windows 显示缩放下
+ * 是小数——侧栏落在小数像素上，图标和文字取整方向不同，部分图标会跳 1px。
+ * fixed 按视口摆放，不参与滚动偏移的运算。网格的第一列只当占位。
  */
 .side {
-  position: sticky;
+  position: fixed;
   top: 0;
-  align-self: start;
+  left: 0;
+  width: var(--side-w);
   height: 100vh;
+  transition: width 0.3s ease;
   display: flex;
   flex-direction: column;
   gap: var(--s-5);
@@ -696,7 +717,9 @@ const current = computed(() => NAV.find((n) => n.key === active.value))
 
 
 /* ── 主区 ───────────────────────────────────── */
+/* 侧栏是 fixed、不占网格位，主区要自己站到第二列，否则会顶进第一列 */
 .main {
+  grid-column: 2;
   padding: var(--s-6) var(--s-6) var(--s-7);
   max-width: 1600px;
 }
diff --git a/web/components/ToastHost.vue b/web/components/ToastHost.vue
index 384238d..ee98ec1 100644
--- a/web/components/ToastHost.vue
+++ b/web/components/ToastHost.vue
@@ -1,12 +1,45 @@
 <script setup lang="ts">
 /**
- * 轻提示的渲染宿主，挂在外壳根部。进场从右滑入，退场上移淡出；
- * 点一下立刻消掉。内容来自 web/toast.ts 的单例队列。
+ * 轻提示的渲染宿主，挂在外壳根部。进场从右滑入，退场上移淡出。
+ * 点一下：普通提示立刻消掉；错误提示是要拿去粘贴求助的，点击复制而不是关闭，
+ * 消失交给 toast.ts 的定时器。内容来自 web/toast.ts 的单例队列。
  */
+import { ref } from 'vue'
 import { dismiss, toasts } from '../toast'
+import type { Toast } from '../toast'
 import IconOk from '~icons/ri/checkbox-circle-line'
 import IconErr from '~icons/ri/error-warning-line'
 import IconInfo from '~icons/ri/information-line'
+
+/** 已复制的错误提示：hint 原地换成「已复制到剪贴板」作为反馈。 */
+const copied = ref(new Set<number>())
+
+async function onClick(t: Toast) {
+  if (t.kind !== 'error') {
+    dismiss(t.id)
+    return
+  }
+  const ok = await copyText([t.message, t.hint].filter(Boolean).join('\n'))
+  if (ok) copied.value = new Set(copied.value).add(t.id)
+}
+
+/** 经 http 从局域网访问时没有 navigator.clipboard（非安全上下文），退回 execCommand。 */
+async function copyText(text: string): Promise<boolean> {
+  try {
+    await navigator.clipboard.writeText(text)
+    return true
+  } catch {
+    const area = document.createElement('textarea')
+    area.value = text
+    area.style.position = 'fixed'
+    area.style.opacity = '0'
+    document.body.appendChild(area)
+    area.select()
+    const ok = document.execCommand('copy')
+    area.remove()
+    return ok
+  }
+}
 </script>
 
 <template>
@@ -16,14 +49,16 @@ import IconInfo from '~icons/ri/information-line'
         v-for="t in toasts"
         :key="t.id"
         :class="['tst', t.kind === 'error' && 'is-error']"
-        @click="dismiss(t.id)"
+        :title="t.kind === 'error' ? '点击复制错误信息' : undefined"
+        @click="onClick(t)"
       >
         <IconErr v-if="t.kind === 'error'" class="tico" />
         <IconInfo v-else-if="t.kind === 'info'" class="tico is-info" />
         <IconOk v-else class="tico" />
         <div class="tbody">
           <strong class="tmsg">{{ t.message }}</strong>
-          <span v-if="t.hint" class="thint">{{ t.hint }}</span>
+          <span v-if="copied.has(t.id)" class="thint">已复制到剪贴板</span>
+          <span v-else-if="t.hint" class="thint">{{ t.hint }}</span>
         </div>
       </div>
     </TransitionGroup>
diff --git a/web/nav.ts b/web/nav.ts
index f582488..d21fd6d 100644
--- a/web/nav.ts
+++ b/web/nav.ts
@@ -7,7 +7,7 @@ import IconRoute from '~icons/ri/route-line'
 import IconDashboard from '~icons/ri/dashboard-line'
 import IconConfig from '~icons/ri/file-list-3-line'
 import IconRules from '~icons/ri/filter-3-line'
-import IconRequests from '~icons/ri/pulse-line'
+import IconLogs from '~icons/ri/terminal-line'
 import IconConnections from '~icons/ri/links-line'
 import IconSettings from '~icons/ri/settings-3-line'
 import type { Component } from 'vue'
@@ -23,7 +23,7 @@ export const NAV: NavItem[] = [
   { key: 'router', label: '路由', icon: IconRoute },
   { key: 'config', label: '配置', icon: IconConfig },
   { key: 'rules', label: '规则', icon: IconRules },
-  { key: 'requests', label: '请求', icon: IconRequests },
+  { key: 'requests', label: '日志', icon: IconLogs },
   { key: 'connections', label: '连接', icon: IconConnections },
   { key: 'settings', label: '设置', icon: IconSettings },
 ]
diff --git a/web/styles/tokens.css b/web/styles/tokens.css
index c84d125..f45916e 100644
--- a/web/styles/tokens.css
+++ b/web/styles/tokens.css
@@ -182,6 +182,12 @@ html {
   scrollbar-gutter: stable;
 }
 
+/* 模态框开着时锁住背后的页面滚动。:modal 只匹配 showModal() 打开的 dialog；
+   滚动条的位置由上面的 scrollbar-gutter 常驻留出，锁定解锁都不会横向跳动 */
+html:has(:modal) {
+  overflow: hidden;
+}
+
 body {
   margin: 0;
   background: var(--c-bg);