fix: visual fixes — dark theme default, sidebar, dashboard cards, timeline dots, header counts

- Set data-theme=dark as default in index.html, useTheme defaults to 'dark' (issues 1, 10)
- Rename "Cron" to "Cron 管理" in sidebar (issue 2)
- Set card grid gap to 14px per design spec (issue 3)
- Show D-grade profile names below health bar chart (issue 4)
- Remove R/F/H/OK text from timeline, use colored dots with hover tooltip (issue 5)
- Wire live online/running/offline counts via usePolling in header, add offline badge (issue 9)
- Fix search placeholder to "搜索 Profile / 任务 / Cron / 事件..." (issue 9)

Co-Authored-By: Claude <noreply@anthropic.com>

frontend/index.html

@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="zh-CN">
+<html lang="zh-CN" data-theme="dark">
   <head>
     <meta charset="UTF-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />

frontend/src/components/layout/AppLayout.tsx

@@ -1,6 +1,8 @@
 import { useState, type ReactNode } from 'react'
 import { useNavigate, useLocation } from 'react-router-dom'
 import { useTheme } from '../../hooks/useTheme'
+import { usePolling } from '../../hooks/usePolling'
+import { getDashboardSummary } from '../../api/dashboard'
 import Sidebar from './Sidebar'
 import Header from './Header'
 import MobileNav from './MobileNav'
@@ -27,6 +29,7 @@ export interface AppLayoutProps {
   breadcrumb?: string
   onlineCount?: number
   runningCount?: number
+  offlineCount?: number
   onSearch?: (query: string) => any
   onSearchNavigate?: (value: string) => void
 }
@@ -36,6 +39,7 @@ export default function AppLayout({
   breadcrumb,
   onlineCount = 0,
   runningCount = 0,
+  offlineCount = 0,
   onSearch,
   onSearchNavigate,
 }: AppLayoutProps) {
@@ -52,6 +56,23 @@ export default function AppLayout({
 
   const sidebarWidth = isTablet ? 180 : 220
 
+  /* ---- live header counts ---- */
+  const [liveOnline, setLiveOnline] = useState(0)
+  const [liveRunning, setLiveRunning] = useState(0)
+  const [liveOffline, setLiveOffline] = useState(0)
+  usePolling(async () => {
+    try {
+      const res = await getDashboardSummary()
+      setLiveOnline(res.data.online_count)
+      setLiveRunning(res.data.running_tasks)
+      setLiveOffline(res.data.offline_count)
+    } catch { /* ignore polling errors */ }
+  }, 30_000)
+
+  const hOnline = onlineCount || liveOnline
+  const hRunning = runningCount || liveRunning
+  const hOffline = offlineCount || liveOffline
+
   if (isMobile) {
     return (
       <div className="min-h-screen flex flex-col" style={{ background: 'var(--bg-root)' }}>
@@ -120,8 +141,9 @@ export default function AppLayout({
       <div style={{ gridArea: 'header' }}>
         <Header
           breadcrumb={breadcrumb}
-          onlineCount={onlineCount}
-          runningCount={runningCount}
+          onlineCount={hOnline}
+          runningCount={hRunning}
+          offlineCount={hOffline}
           onSearch={onSearch}
           onSearchNavigate={onSearchNavigate}
           theme={theme}

frontend/src/components/layout/Header.tsx

@@ -7,6 +7,7 @@ export interface HeaderProps {
   breadcrumb?: string
   onlineCount?: number
   runningCount?: number
+  offlineCount?: number
   onSearch?: (query: string) => any
   onSearchNavigate?: (value: string) => void
   theme: string
@@ -17,6 +18,7 @@ export default function Header({
   breadcrumb,
   onlineCount = 0,
   runningCount = 0,
+  offlineCount = 0,
   onSearch,
   onSearchNavigate,
   theme,
@@ -56,12 +58,13 @@ export default function Header({
 
       {/* Search */}
       {onSearch && (
-        <SearchBox onSearch={onSearch} onItemClick={onSearchNavigate} placeholder="搜索功能、任务、日志..." />
+        <SearchBox onSearch={onSearch} onItemClick={onSearchNavigate} placeholder="搜索 Profile / 任务 / Cron / 事件..." />
       )}
 
       {/* Status badges */}
       <Badge variant="success">在线 {onlineCount}</Badge>
       <Badge variant="honey">运行中 {runningCount}</Badge>
+      <Badge variant="danger">离线 {offlineCount}</Badge>
 
       {/* Theme toggle */}
       <button

frontend/src/components/layout/Sidebar.tsx

@@ -30,7 +30,7 @@ const sections: NavSection[] = [
     title: '任务编排',
     items: [
       { label: '看板追踪', icon: '📋', path: '/kanban' },
-      { label: 'Cron', icon: '⏰', path: '/cron', requiredRole: 'operator' },
+      { label: 'Cron 管理', icon: '⏰', path: '/cron', requiredRole: 'operator' },
       { label: '事件管理', icon: '🔔', path: '/events' },
     ],
   },

frontend/src/components/ui/Timeline.tsx

@@ -1,9 +1,7 @@
-import type { ReactNode } from "react"
-
 export interface TimelineEvent {
   time: string
   type: string
-  label: ReactNode
+  tooltip?: string
   color?: string
 }
 
@@ -35,10 +33,10 @@ export default function Timeline({ events, className = "" }: TimelineProps) {
               >
                 <div className="absolute bottom-full left-1/2 -translate-x-1/2 mb-2 px-2 py-1 text-[11px] whitespace-nowrap rounded-[var(--radius-sm)] opacity-0 group-hover:opacity-100 transition-opacity pointer-events-none z-10"
                   style={{ backgroundColor: "var(--bg-elevated)", color: "var(--text)" }}>
-                  {evt.time}
+                  <div>{evt.time}</div>
+                  {evt.tooltip && <div style={{ color: "var(--text-dim)" }}>{evt.tooltip}</div>}
                 </div>
               </div>
-              <div className="text-[11px] text-[var(--text-dim)] mt-1">{evt.label}</div>
             </div>
             {!isLast && (
               <div

frontend/src/hooks/useTheme.ts

@@ -1,20 +1,15 @@
 import { useState, useEffect } from 'react'
 
-type Theme = 'dark' | 'light' | 'system'
+type Theme = 'dark' | 'light'
 
 export function useTheme() {
   const [theme, setTheme] = useState<Theme>(() => {
-    return (localStorage.getItem('hive-theme') as Theme) || 'system'
+    return (localStorage.getItem('hive-theme') as Theme) || 'dark'
   })
 
   useEffect(() => {
     const root = document.documentElement
-    if (theme === 'system') {
-      const prefersDark = window.matchMedia('(prefers-color-scheme: dark)').matches
-      root.setAttribute('data-theme', prefersDark ? 'dark' : 'light')
-    } else {
-      root.setAttribute('data-theme', theme)
-    }
+    root.setAttribute('data-theme', theme)
     localStorage.setItem('hive-theme', theme)
   }, [theme])
 

frontend/src/pages/DashboardPage.tsx

@@ -62,37 +62,49 @@ function HealthBarChart({
   const maxVal = Math.max(dist.A, dist.B, dist.C, dist.D, 1)
 
   return (
-    <div className="space-y-3 mt-2">
-      {GRADE_META.map(({ key, color }) => {
-        const val = dist[key as keyof typeof dist] as number
-        const pct = (val / maxVal) * 100
-        return (
-          <div
-            key={key}
-            className="flex items-center gap-3 cursor-pointer group"
-            onClick={() => onBarClick(key)}
-          >
-            <span
-              className="w-5 text-center text-[13px] font-bold shrink-0"
-              style={{ color }}
+    <div>
+      <div className="space-y-3 mt-2">
+        {GRADE_META.map(({ key, color }) => {
+          const val = dist[key as keyof typeof dist] as number
+          const pct = (val / maxVal) * 100
+          return (
+            <div
+              key={key}
+              className="flex items-center gap-3 cursor-pointer group"
+              onClick={() => onBarClick(key)}
             >
-              {key}
-            </span>
-            <div className="flex-1 h-6 rounded-[var(--radius-sm)] bg-[var(--bg-hover)] overflow-hidden relative">
-              <div
-                className="h-full rounded-[var(--radius-sm)] transition-all duration-500 group-hover:opacity-80"
-                style={{
-                  width: `${Math.max(pct, 4)}%`,
-                  backgroundColor: color,
-                }}
-              />
+              <span
+                className="w-5 text-center text-[13px] font-bold shrink-0"
+                style={{ color }}
+              >
+                {key}
+              </span>
+              <div className="flex-1 h-6 rounded-[var(--radius-sm)] bg-[var(--bg-hover)] overflow-hidden relative">
+                <div
+                  className="h-full rounded-[var(--radius-sm)] transition-all duration-500 group-hover:opacity-80"
+                  style={{
+                    width: `${Math.max(pct, 4)}%`,
+                    backgroundColor: color,
+                  }}
+                />
+              </div>
+              <span className="w-8 text-right text-[13px] shrink-0" style={{ color: 'var(--text-dim)' }}>
+                {val}
+              </span>
             </div>
-            <span className="w-8 text-right text-[13px] shrink-0" style={{ color: 'var(--text-dim)' }}>
-              {val}
+          )
+        })}
+      </div>
+      {dist.d_profiles && dist.d_profiles.length > 0 && (
+        <div className="mt-3 pt-3 border-t" style={{ borderColor: 'var(--border)' }}>
+          <span className="text-[12px]" style={{ color: 'var(--text-dim)' }}>D 级 Profile: </span>
+          {dist.d_profiles.map((name) => (
+            <span key={name} className="inline-block text-[12px] px-2 py-0.5 mr-1 mb-1 rounded-[var(--radius-sm)]" style={{ background: 'var(--bg-hover)', color: 'var(--red)' }}>
+              {name}
             </span>
-          </div>
-        )
-      })}
+          ))}
+        </div>
+      )}
     </div>
   )
 }
@@ -186,28 +198,27 @@ export default function DashboardPage() {
   }
 
   /* ---------- trend -> timeline events ---------- */
-  const timelineEvents: TimelineEvent[] = trend.map((item) => ({
-    time: hourLabel(item.hour),
-    type: item.heartbeat_timeouts > 0 ? 'red' : item.feishu_disconnects > 0 ? 'orange' : item.restarts > 0 ? 'orange' : 'green',
-    label: (
-      <span className="flex gap-2 text-[11px]">
-        {item.restarts > 0 && <span style={{ color: 'var(--yellow)' }}>R:{item.restarts}</span>}
-        {item.feishu_disconnects > 0 && <span style={{ color: 'var(--orange)' }}>F:{item.feishu_disconnects}</span>}
-        {item.heartbeat_timeouts > 0 && <span style={{ color: 'var(--red)' }}>H:{item.heartbeat_timeouts}</span>}
-        {item.restarts === 0 && item.feishu_disconnects === 0 && item.heartbeat_timeouts === 0 && (
-          <span style={{ color: 'var(--green)' }}>OK</span>
-        )}
-      </span>
-    ),
-    color: trendColor(item),
-  }))
+  const timelineEvents: TimelineEvent[] = trend.map((item) => {
+    const details: string[] = []
+    if (item.heartbeat_timeouts > 0) details.push(`心跳超时 ${item.heartbeat_timeouts}`)
+    if (item.feishu_disconnects > 0) details.push(`飞书断连 ${item.feishu_disconnects}`)
+    if (item.restarts > 0) details.push(`重启 ${item.restarts}`)
+    const tooltipText = details.length > 0 ? details.join(' / ') : '正常'
+
+    return {
+      time: hourLabel(item.hour),
+      type: item.heartbeat_timeouts > 0 ? 'red' : item.feishu_disconnects > 0 ? 'orange' : item.restarts > 0 ? 'orange' : 'green',
+      tooltip: tooltipText,
+      color: trendColor(item),
+    }
+  })
 
   return (
     <div>
       <h2 style={{ color: 'var(--text)', fontSize: 18, fontWeight: 600 }}>蜂群总览</h2>
 
       {/* ---- summary cards ---- */}
-      <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-4 mt-4">
+      <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-[14px] mt-4">
         <Card
           label="在线 Gateway"
           value={summary.online_count}
@@ -237,7 +248,7 @@ export default function DashboardPage() {
       </div>
 
       {/* ---- health + trend ---- */}
-      <div className="grid grid-cols-1 lg:grid-cols-2 gap-4 mt-4">
+      <div className="grid grid-cols-1 lg:grid-cols-2 gap-[14px] mt-4">
         {/* health distribution */}
         <div
           className="rounded-[var(--radius)] p-4"
@@ -281,7 +292,7 @@ export default function DashboardPage() {
       </div>
 
       {/* ---- kanban + cron ---- */}
-      <div className="grid grid-cols-1 lg:grid-cols-2 gap-4 mt-4">
+      <div className="grid grid-cols-1 lg:grid-cols-2 gap-[14px] mt-4">
         {/* kanban overview */}
         <div
           className="rounded-[var(--radius)] p-4"

frontend/src/pages/GatewayPage.tsx

@@ -42,12 +42,7 @@ const eventToTimeline = (e: GatewayEvent): TimelineEvent => {
   return {
     time: e.time,
     type: e.type,
-    label: (
-      <div className="flex flex-col items-center text-[11px]">
-        <span className="font-medium" style={{ color: 'var(--text)' }}>{labelMap[e.type] || e.type}</span>
-        <span style={{ color: 'var(--text-dim)' }}>{e.profile}</span>
-      </div>
-    ),
+    tooltip: `${labelMap[e.type] || e.type} — ${e.profile}`,
     color: colorMap[e.type],
   }
 }