diff --git a/apps/web/messages/en.json b/apps/web/messages/en.json
index ca447870..274bcd8d 100644
--- a/apps/web/messages/en.json
+++ b/apps/web/messages/en.json
@@ -58,7 +58,8 @@
     "users": "Users",
     "notifications": "Notifications",
     "billing": "Billing",
-    "help": "Help"
+    "help": "Help",
+    "drift": "Drift Detection"
   },
   "locale": {
     "switch": "Switch Language",
@@ -924,5 +925,36 @@
   "emptyState": {
     "noData": "--",
     "comingSoon": "Integration pending"
+  },
+  "drift": {
+    "title": "Config Drift Detection",
+    "subtitle": "GitOps Guardian — Detects drift between K8s actual state and Git YAML",
+    "scan": "Scan Now",
+    "scanning": "Scanning...",
+    "noReports": "No drift reports yet",
+    "noReportsHint": "CronJob scans hourly automatically, or click \"Scan Now\" to trigger manually",
+    "noDrift": "No Drift",
+    "reportId": "Report ID",
+    "scannedAt": "Scanned At",
+    "namespace": "Namespace",
+    "triggeredBy": "Triggered By",
+    "highCount": "High",
+    "mediumCount": "Medium",
+    "infoCount": "Info",
+    "status": "Status",
+    "driftLevel": {
+      "high": "High",
+      "medium": "Medium",
+      "info": "Info"
+    },
+    "interpretation": "Nemotron Intent Analysis",
+    "noInterpretation": "No analysis needed (no drift)",
+    "rollback": "Rollback to Git",
+    "adopt": "Adopt Change",
+    "rollbackConfirm": "Rollback this resource to Git state?",
+    "adoptConfirm": "Adopt this change and update Git?",
+    "pending": "Pending",
+    "resolved": "Resolved",
+    "ignored": "Ignored"
   }
-}
\ No newline at end of file
+}
diff --git a/apps/web/messages/zh-TW.json b/apps/web/messages/zh-TW.json
index 7a6e0a49..eac763e5 100644
--- a/apps/web/messages/zh-TW.json
+++ b/apps/web/messages/zh-TW.json
@@ -58,7 +58,8 @@
     "users": "使用者",
     "notifications": "通知",
     "billing": "帳單",
-    "help": "說明"
+    "help": "說明",
+    "drift": "漂移偵測"
   },
   "locale": {
     "switch": "切換語系",
@@ -925,5 +926,36 @@
   "emptyState": {
     "noData": "--",
     "comingSoon": "資料尚未整合"
+  },
+  "drift": {
+    "title": "配置漂移偵測",
+    "subtitle": "GitOps 守門員 — 偵測 K8s 實際狀態 vs Git YAML 的漂移",
+    "scan": "立即掃描",
+    "scanning": "掃描中...",
+    "noReports": "目前無漂移報告",
+    "noReportsHint": "CronJob 每小時自動掃描，或點擊「立即掃描」手動觸發",
+    "noDrift": "無漂移",
+    "reportId": "報告 ID",
+    "scannedAt": "掃描時間",
+    "namespace": "Namespace",
+    "triggeredBy": "觸發來源",
+    "highCount": "高",
+    "mediumCount": "中",
+    "infoCount": "低",
+    "status": "狀態",
+    "driftLevel": {
+      "high": "高",
+      "medium": "中",
+      "info": "低"
+    },
+    "interpretation": "Nemotron 意圖分析",
+    "noInterpretation": "無需分析（無漂移）",
+    "rollback": "覆蓋回 Git",
+    "adopt": "承認變更",
+    "rollbackConfirm": "確定要將此資源覆蓋回 Git 狀態嗎？",
+    "adoptConfirm": "確定要將此變更承認並更新至 Git 嗎？",
+    "pending": "待處理",
+    "resolved": "已解決",
+    "ignored": "已忽略"
   }
-}
\ No newline at end of file
+}
diff --git a/apps/web/src/app/[locale]/drift/page.tsx b/apps/web/src/app/[locale]/drift/page.tsx
new file mode 100644
index 00000000..23989dff
--- /dev/null
+++ b/apps/web/src/app/[locale]/drift/page.tsx
@@ -0,0 +1,324 @@
+'use client'
+
+/**
+ * Config Drift Detection Page - 配置漂移偵測
+ * =============================================
+ * Phase 25 P2: GitOps 守門員
+ * 偵測 K8s 實際狀態 vs Git YAML 漂移
+ *
+ * API: /api/v1/drift/scan, /api/v1/drift/reports
+ * CronJob: drift-scanner (每小時自動)
+ *
+ * 建立時間: 2026-04-04 (台北時區)
+ * 建立者: Claude Code (Phase 25 P2)
+ * 關聯設計: docs/superpowers/specs/2026-04-04-nemotron-active-defense-design.md 方向三
+ */
+
+import { useState, useEffect, useCallback } from 'react'
+import { useTranslations } from 'next-intl'
+import { AppLayout } from '@/components/layout'
+import { cn } from '@/lib/utils'
+import {
+  Diff, RefreshCw, AlertTriangle, CheckCircle2,
+  Clock, Terminal, GitMerge, Info,
+} from 'lucide-react'
+
+// =============================================================================
+// Types
+// =============================================================================
+
+interface DriftReport {
+  report_id: string
+  scanned_at: string
+  namespace: string
+  triggered_by: string
+  high_count: number
+  medium_count: number
+  info_count: number
+  interpretation: string | null
+  status: 'pending' | 'resolved' | 'ignored'
+  created_at: string
+  resolved_at: string | null
+}
+
+interface ScanResult {
+  report_id: string
+  summary: string
+  high_count: number
+  medium_count: number
+  info_count: number
+  has_critical_drift: boolean
+  interpretation: string | null
+}
+
+// =============================================================================
+// Helpers
+// =============================================================================
+
+const getApiBase = () => {
+  if (typeof window === 'undefined') return ''
+  return process.env.NEXT_PUBLIC_API_URL ?? ''
+}
+
+const fmtTime = (iso: string) => {
+  try {
+    return new Date(iso).toLocaleString('zh-TW', {
+      year: 'numeric', month: '2-digit', day: '2-digit',
+      hour: '2-digit', minute: '2-digit',
+    })
+  } catch {
+    return iso
+  }
+}
+
+// =============================================================================
+// Sub-components
+// =============================================================================
+
+function DriftLevelBadge({ high, medium, info, t }: {
+  high: number; medium: number; info: number
+  t: (k: string) => string
+}) {
+  if (high === 0 && medium === 0 && info === 0) {
+    return (
+      <span className="inline-flex items-center gap-1 px-2 py-0.5 rounded text-[11px] font-medium bg-status-healthy/10 text-status-healthy border border-status-healthy/20">
+        <CheckCircle2 size={10} />
+        {t('noDrift')}
+      </span>
+    )
+  }
+  return (
+    <div className="flex items-center gap-1.5">
+      {high > 0 && (
+        <span className="inline-flex items-center gap-1 px-2 py-0.5 rounded text-[11px] font-medium bg-status-critical/10 text-status-critical border border-status-critical/20">
+          <AlertTriangle size={10} />
+          {t('highCount')} {high}
+        </span>
+      )}
+      {medium > 0 && (
+        <span className="inline-flex items-center gap-1 px-2 py-0.5 rounded text-[11px] font-medium bg-status-warning/10 text-status-warning border border-status-warning/20">
+          <Info size={10} />
+          {t('mediumCount')} {medium}
+        </span>
+      )}
+      {info > 0 && (
+        <span className="inline-flex items-center gap-1 px-2 py-0.5 rounded text-[11px] font-medium bg-neutral-100 text-neutral-500 border border-neutral-200">
+          {t('infoCount')} {info}
+        </span>
+      )}
+    </div>
+  )
+}
+
+function StatusBadge({ status, t }: { status: DriftReport['status']; t: (k: string) => string }) {
+  const styles: Record<string, string> = {
+    pending:  'bg-status-warning/10 text-status-warning border-status-warning/20',
+    resolved: 'bg-status-healthy/10 text-status-healthy border-status-healthy/20',
+    ignored:  'bg-neutral-100 text-neutral-400 border-neutral-200',
+  }
+  return (
+    <span className={cn(
+      'inline-flex items-center px-2 py-0.5 rounded text-[11px] font-medium border',
+      styles[status] ?? styles.ignored
+    )}>
+      {t(status)}
+    </span>
+  )
+}
+
+// =============================================================================
+// Main Page
+// =============================================================================
+
+export default function DriftPage({ params }: { params: { locale: string } }) {
+  const t = useTranslations('drift')
+  const [reports, setReports] = useState<DriftReport[]>([])
+  const [loading, setLoading] = useState(true)
+  const [scanning, setScanning] = useState(false)
+  const [scanResult, setScanResult] = useState<ScanResult | null>(null)
+  const [error, setError] = useState<string | null>(null)
+
+  const fetchReports = useCallback(async () => {
+    setLoading(true)
+    setError(null)
+    try {
+      const res = await fetch(`${getApiBase()}/api/v1/drift/reports?limit=20`)
+      if (!res.ok) throw new Error(`HTTP ${res.status}`)
+      const data = await res.json()
+      setReports(data.items ?? [])
+    } catch (e) {
+      setError(e instanceof Error ? e.message : 'Failed to fetch')
+    } finally {
+      setLoading(false)
+    }
+  }, [])
+
+  useEffect(() => { fetchReports() }, [fetchReports])
+
+  const handleScan = async () => {
+    setScanning(true)
+    setScanResult(null)
+    try {
+      const res = await fetch(`${getApiBase()}/api/v1/drift/scan`, {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ namespace: 'awoooi-prod', triggered_by: 'web_manual' }),
+      })
+      if (!res.ok) throw new Error(`HTTP ${res.status}`)
+      const data: ScanResult = await res.json()
+      setScanResult(data)
+      // Refresh reports list
+      await fetchReports()
+    } catch (e) {
+      setError(e instanceof Error ? e.message : 'Scan failed')
+    } finally {
+      setScanning(false)
+    }
+  }
+
+  return (
+    <AppLayout locale={params.locale}>
+      <div className="flex flex-col h-full overflow-auto bg-white">
+        {/* Header */}
+        <div className="flex items-center justify-between px-6 py-4 border-b border-neutral-100">
+          <div className="flex items-center gap-3">
+            <Diff size={18} className="text-neutral-400" />
+            <div>
+              <h1 className="text-[13px] font-semibold text-neutral-800 leading-tight">
+                {t('title')}
+              </h1>
+              <p className="text-[11px] text-neutral-400 leading-tight mt-0.5">
+                {t('subtitle')}
+              </p>
+            </div>
+          </div>
+          <div className="flex items-center gap-2">
+            <button
+              onClick={fetchReports}
+              disabled={loading}
+              className="p-1.5 rounded text-neutral-400 hover:text-neutral-600 hover:bg-neutral-50 transition-colors disabled:opacity-40"
+            >
+              <RefreshCw size={13} className={loading ? 'animate-spin' : ''} />
+            </button>
+            <button
+              onClick={handleScan}
+              disabled={scanning}
+              className={cn(
+                'flex items-center gap-1.5 px-3 py-1.5 rounded text-[11px] font-medium transition-colors',
+                scanning
+                  ? 'bg-neutral-100 text-neutral-400 cursor-not-allowed'
+                  : 'bg-neutral-900 text-white hover:bg-neutral-700'
+              )}
+            >
+              {scanning ? (
+                <>
+                  <RefreshCw size={11} className="animate-spin" />
+                  {t('scanning')}
+                </>
+              ) : (
+                <>
+                  <GitMerge size={11} />
+                  {t('scan')}
+                </>
+              )}
+            </button>
+          </div>
+        </div>
+
+        {/* Scan Result Banner */}
+        {scanResult && (
+          <div className={cn(
+            'mx-6 mt-4 px-4 py-3 rounded border text-[12px]',
+            scanResult.has_critical_drift
+              ? 'bg-status-critical/5 border-status-critical/20 text-status-critical'
+              : 'bg-status-healthy/5 border-status-healthy/20 text-status-healthy'
+          )}>
+            <div className="flex items-center gap-2 font-medium">
+              {scanResult.has_critical_drift
+                ? <AlertTriangle size={13} />
+                : <CheckCircle2 size={13} />
+              }
+              {scanResult.summary}
+              {(scanResult.high_count > 0 || scanResult.medium_count > 0) && (
+                <span className="ml-2 text-neutral-500 font-normal">
+                  — High: {scanResult.high_count}, Medium: {scanResult.medium_count}
+                </span>
+              )}
+            </div>
+            {scanResult.interpretation && (
+              <p className="mt-1.5 text-neutral-600 font-normal pl-5">
+                {scanResult.interpretation}
+              </p>
+            )}
+          </div>
+        )}
+
+        {/* Error */}
+        {error && (
+          <div className="mx-6 mt-4 px-4 py-3 rounded border border-status-critical/20 bg-status-critical/5 text-status-critical text-[12px]">
+            {error}
+          </div>
+        )}
+
+        {/* Content */}
+        <div className="flex-1 px-6 py-4">
+          {loading && reports.length === 0 ? (
+            <div className="flex items-center justify-center h-32 text-neutral-400">
+              <RefreshCw size={16} className="animate-spin mr-2" />
+              <span className="text-[12px]">Loading...</span>
+            </div>
+          ) : reports.length === 0 ? (
+            <div className="flex flex-col items-center justify-center h-48 text-neutral-400">
+              <Terminal size={32} className="mb-3 opacity-30" />
+              <p className="text-[13px] font-medium text-neutral-500">{t('noReports')}</p>
+              <p className="text-[11px] text-neutral-400 mt-1 text-center max-w-xs">{t('noReportsHint')}</p>
+            </div>
+          ) : (
+            <div className="space-y-2">
+              {reports.map((report) => (
+                <div
+                  key={report.report_id}
+                  className="border border-neutral-100 rounded-lg px-4 py-3 hover:border-neutral-200 transition-colors"
+                >
+                  <div className="flex items-center justify-between gap-3">
+                    {/* Left: ID + time */}
+                    <div className="flex items-center gap-3 min-w-0">
+                      <code className="text-[11px] font-mono text-neutral-500 bg-neutral-50 px-1.5 py-0.5 rounded shrink-0">
+                        {report.report_id.slice(0, 8)}
+                      </code>
+                      <DriftLevelBadge
+                        high={report.high_count}
+                        medium={report.medium_count}
+                        info={report.info_count}
+                        t={t}
+                      />
+                    </div>
+                    {/* Right: status + time */}
+                    <div className="flex items-center gap-2 shrink-0">
+                      <StatusBadge status={report.status} t={t} />
+                      <span className="text-[11px] text-neutral-400 flex items-center gap-1">
+                        <Clock size={10} />
+                        {fmtTime(report.scanned_at)}
+                      </span>
+                    </div>
+                  </div>
+                  {/* Interpretation */}
+                  {report.interpretation && (
+                    <p className="mt-2 text-[11px] text-neutral-500 pl-1 border-l-2 border-neutral-100">
+                      {report.interpretation}
+                    </p>
+                  )}
+                  {/* Metadata */}
+                  <div className="flex items-center gap-4 mt-2 text-[10px] text-neutral-400">
+                    <span>{t('namespace')}: <span className="font-mono">{report.namespace}</span></span>
+                    <span>{t('triggeredBy')}: {report.triggered_by}</span>
+                  </div>
+                </div>
+              ))}
+            </div>
+          )}
+        </div>
+      </div>
+    </AppLayout>
+  )
+}
diff --git a/apps/web/src/components/layout/sidebar.tsx b/apps/web/src/components/layout/sidebar.tsx
index 6aa91136..fdb4d9dd 100644
--- a/apps/web/src/components/layout/sidebar.tsx
+++ b/apps/web/src/components/layout/sidebar.tsx
@@ -33,7 +33,7 @@ import {
   Wrench, Package, Ticket, DollarSign, Zap, FileText,
   BookOpen, Terminal, AppWindow, Server,
   Users, BellRing, CreditCard, HelpCircle, Settings,
-  ChevronLeft, ChevronRight,
+  ChevronLeft, ChevronRight, Diff,
 } from 'lucide-react'
 // Phase 8.0 #15: 改用 approval store SSE (移除 polling)
 import { useApprovalStore } from '@/stores/approval.store'
@@ -94,6 +94,8 @@ const NAV_SECTIONS: NavSection[] = [
     sectionLabel: '',
     items: [
       { id: 'auto-repair',  href: '/auto-repair',  labelKey: 'autoRepair',  Icon: Wrench },
+      // 2026-04-04 Claude Code: Phase 25 P2 — Config Drift Detection
+      { id: 'drift',        href: '/drift',        labelKey: 'drift',       Icon: Diff },
       { id: 'deployments',  href: '/deployments',  labelKey: 'deployments', Icon: Package },
       { id: 'tickets',      href: '/tickets',      labelKey: 'tickets',     Icon: Ticket },
       { id: 'cost',         href: '/cost',         labelKey: 'cost',        Icon: DollarSign },