diff --git a/src/components/ui/surface.tsx b/src/components/ui/surface.tsx
index e16eba2..4a69989 100644
--- a/src/components/ui/surface.tsx
+++ b/src/components/ui/surface.tsx
@@ -190,23 +190,51 @@ export function SegmentedNav<T extends string>({
   tabs,
   active,
   onChange,
+  idPrefix,
+  ariaLabel,
   className,
 }: {
   tabs: readonly { id: T; label: string; icon?: SurfaceIcon }[];
   active: T;
   onChange: (id: T) => void;
+  idPrefix: string;
+  ariaLabel: string;
   className?: string;
 }) {
+  const activateFromKeyboard = (event: React.KeyboardEvent<HTMLButtonElement>, currentIndex: number) => {
+    let nextIndex: number | null = null;
+    if (event.key === 'ArrowRight') nextIndex = (currentIndex + 1) % tabs.length;
+    if (event.key === 'ArrowLeft') nextIndex = (currentIndex - 1 + tabs.length) % tabs.length;
+    if (event.key === 'Home') nextIndex = 0;
+    if (event.key === 'End') nextIndex = tabs.length - 1;
+    if (nextIndex === null) return;
+    event.preventDefault();
+    const next = tabs[nextIndex];
+    onChange(next.id);
+    window.requestAnimationFrame(() => document.getElementById(`${idPrefix}-tab-${next.id}`)?.focus());
+  };
+
   return (
     <div className={cn('rounded-2xl border border-white/70 bg-white/90 p-1 shadow-sm backdrop-blur-xl', className)}>
-      <div className="grid gap-1" style={{ gridTemplateColumns: `repeat(${tabs.length}, minmax(0, 1fr))` }}>
-        {tabs.map(({ id, label, icon: Icon }) => {
+      <div
+        role="tablist"
+        aria-label={ariaLabel}
+        className="grid gap-1"
+        style={{ gridTemplateColumns: `repeat(${tabs.length}, minmax(0, 1fr))` }}
+      >
+        {tabs.map(({ id, label, icon: Icon }, index) => {
           const isActive = active === id;
           return (
             <button
               key={id}
+              id={`${idPrefix}-tab-${id}`}
               type="button"
+              role="tab"
+              aria-selected={isActive}
+              aria-controls={`${idPrefix}-panel-${id}`}
+              tabIndex={isActive ? 0 : -1}
               onClick={() => onChange(id)}
+              onKeyDown={event => activateFromKeyboard(event, index)}
               className={cn(
                 'relative flex min-h-10 items-center justify-center gap-1.5 rounded-xl px-2 text-[12px] font-black transition-colors',
                 isActive ? 'text-blue-700' : 'text-slate-400 hover:bg-slate-50 hover:text-slate-600',
diff --git a/src/modules/energy/ElectricModule.tsx b/src/modules/energy/ElectricModule.tsx
index ac95f49..c8fa9c8 100644
--- a/src/modules/energy/ElectricModule.tsx
+++ b/src/modules/energy/ElectricModule.tsx
@@ -24,10 +24,16 @@ export default function ElectricModule() {
       meta="时间单位清晰标注 · 支持日/总览切换"
       actions={<BiHeaderActions domain="electric" />}
     >
-      <SubTabs tabs={SUB_TABS} active={sub} onChange={setSub} />
+      <SubTabs tabs={SUB_TABS} active={sub} onChange={setSub} idPrefix="electric-view" ariaLabel="电能分析视图" />
       <AnimatePresence mode="wait">
         <FadeIn key={sub}>
-          <ElectricView sub={sub} />
+          <div
+            id={`electric-view-panel-${sub}`}
+            role="tabpanel"
+            aria-labelledby={`electric-view-tab-${sub}`}
+          >
+            <ElectricView sub={sub} />
+          </div>
         </FadeIn>
       </AnimatePresence>
     </PageFrame>
diff --git a/src/modules/energy/HydrogenModule.tsx b/src/modules/energy/HydrogenModule.tsx
index d7dc1a0..8ec98c6 100644
--- a/src/modules/energy/HydrogenModule.tsx
+++ b/src/modules/energy/HydrogenModule.tsx
@@ -24,10 +24,16 @@ export default function HydrogenModule() {
       meta="数据单位清晰标注 · 支持日/总览切换"
       actions={<BiHeaderActions domain="hydrogen" />}
     >
-      <SubTabs tabs={SUB_TABS} active={sub} onChange={setSub} />
+      <SubTabs tabs={SUB_TABS} active={sub} onChange={setSub} idPrefix="hydrogen-view" ariaLabel="氢能分析视图" />
       <AnimatePresence mode="wait">
         <FadeIn key={sub}>
-          <HydrogenView sub={sub} />
+          <div
+            id={`hydrogen-view-panel-${sub}`}
+            role="tabpanel"
+            aria-labelledby={`hydrogen-view-tab-${sub}`}
+          >
+            <HydrogenView sub={sub} />
+          </div>
         </FadeIn>
       </AnimatePresence>
     </PageFrame>
diff --git a/src/modules/energy/SubTabs.tsx b/src/modules/energy/SubTabs.tsx
index ff10646..27ce861 100644
--- a/src/modules/energy/SubTabs.tsx
+++ b/src/modules/energy/SubTabs.tsx
@@ -11,12 +11,14 @@ interface Props<T extends string> {
   tabs: readonly SubTab<T>[];
   active: T;
   onChange: (id: T) => void;
+  idPrefix: string;
+  ariaLabel: string;
 }
 
-export default function SubTabs<T extends string>({ tabs, active, onChange }: Props<T>) {
+export default function SubTabs<T extends string>({ tabs, active, onChange, idPrefix, ariaLabel }: Props<T>) {
   return (
     <div className="sticky top-0 z-30 -mx-3 bg-[var(--app-bg)] px-3 pb-2 pt-1 shadow-[0_8px_12px_-12px_rgba(15,23,42,0.08)] md:-mx-6 md:top-12 md:px-6">
-      <SegmentedNav tabs={tabs} active={active} onChange={onChange} />
+      <SegmentedNav tabs={tabs} active={active} onChange={onChange} idPrefix={idPrefix} ariaLabel={ariaLabel} />
     </div>
   );
 }
diff --git a/src/modules/energy/useHashSubTab.test.ts b/src/modules/energy/useHashSubTab.test.ts
new file mode 100644
index 0000000..d00ce6c
--- /dev/null
+++ b/src/modules/energy/useHashSubTab.test.ts
@@ -0,0 +1,16 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { buildHashSubTab, parseHashSubTab } from './useHashSubTab.js';
+
+const tabs = ['daily', 'overview'] as const;
+
+test('parses valid sub tabs and falls back to the module default', () => {
+  assert.equal(parseHashSubTab('#electric/overview', 'electric', tabs), 'overview');
+  assert.equal(parseHashSubTab('#electric/unknown', 'electric', tabs), 'daily');
+  assert.equal(parseHashSubTab('#hydrogen/overview', 'electric', tabs), 'daily');
+});
+
+test('builds a compact default hash and an explicit secondary hash', () => {
+  assert.equal(buildHashSubTab('electric', 'daily', 'daily'), '#electric');
+  assert.equal(buildHashSubTab('electric', 'overview', 'daily'), '#electric/overview');
+});
diff --git a/src/modules/energy/useHashSubTab.ts b/src/modules/energy/useHashSubTab.ts
index 2a74049..1426c91 100644
--- a/src/modules/energy/useHashSubTab.ts
+++ b/src/modules/energy/useHashSubTab.ts
@@ -1,5 +1,19 @@
 import { useEffect, useState } from 'react';
 
+export function parseHashSubTab<T extends string>(
+  hash: string,
+  moduleId: string,
+  subs: readonly T[],
+): T {
+  const [first, second] = hash.replace(/^#/, '').split('/');
+  if (first !== moduleId) return subs[0];
+  return second && (subs as readonly string[]).includes(second) ? second as T : subs[0];
+}
+
+export function buildHashSubTab<T extends string>(moduleId: string, sub: T, defaultSub: T): string {
+  return sub === defaultSub ? `#${moduleId}` : `#${moduleId}/${sub}`;
+}
+
 /**
  * 把模块内子 tab 状态同步到 URL hash 二级段。
  * hash 形如 `#<moduleId>`（= 默认 sub）或 `#<moduleId>/<sub>`。
@@ -11,26 +25,25 @@ export function useHashSubTab<T extends string>(
 ): [T, (sub: T) => void] {
   const defaultSub = subs[0];
 
-  const parse = (): T => {
-    const hash = window.location.hash.slice(1);
-    const [first, second] = hash.split('/');
-    if (first !== moduleId) return defaultSub;
-    if (second && (subs as readonly string[]).includes(second)) return second as T;
-    return defaultSub;
-  };
+  const parse = (): T => parseHashSubTab(window.location.hash, moduleId, subs);
 
   const [sub, setSubState] = useState<T>(parse);
 
   useEffect(() => {
     const onChange = () => setSubState(parse());
     window.addEventListener('hashchange', onChange);
-    return () => window.removeEventListener('hashchange', onChange);
+    window.addEventListener('popstate', onChange);
+    return () => {
+      window.removeEventListener('hashchange', onChange);
+      window.removeEventListener('popstate', onChange);
+    };
   }, [moduleId]);
 
   const setSub = (next: T) => {
+    if (next === sub) return;
     const { pathname, search } = window.location;
-    const newHash = next === defaultSub ? `#${moduleId}` : `#${moduleId}/${next}`;
-    window.history.replaceState(null, '', `${pathname}${search}${newHash}`);
+    const newHash = buildHashSubTab(moduleId, next, defaultSub);
+    window.history.pushState(null, '', `${pathname}${search}${newHash}`);
     setSubState(next);
   };
 
diff --git a/src/modules/mileage/MileageModule.tsx b/src/modules/mileage/MileageModule.tsx
index dfbf4f5..c97044e 100644
--- a/src/modules/mileage/MileageModule.tsx
+++ b/src/modules/mileage/MileageModule.tsx
@@ -32,18 +32,30 @@ export default function MileageModule() {
       compactInfo
     >
       <div className="sticky top-0 z-30 -mx-3 bg-[var(--app-bg)] px-3 pb-2 pt-1 shadow-[0_8px_12px_-12px_rgba(15,23,42,0.08)] md:-mx-6 md:top-12 md:px-6">
-        <SegmentedNav tabs={MILEAGE_TABS} active={activeSubTab} onChange={setActiveSubTab} />
+        <SegmentedNav
+          tabs={MILEAGE_TABS}
+          active={activeSubTab}
+          onChange={setActiveSubTab}
+          idPrefix="mileage-view"
+          ariaLabel="里程分析视图"
+        />
       </div>
 
       <AnimatePresence mode="wait">
         <FadeIn key={activeSubTab}>
-          {activeSubTab === 'monitoring' ? (
-            <MonitoringView />
-          ) : activeSubTab === 'statistics' ? (
-            <StatisticsView />
-          ) : (
-            <DailyReportView />
-          )}
+          <div
+            id={`mileage-view-panel-${activeSubTab}`}
+            role="tabpanel"
+            aria-labelledby={`mileage-view-tab-${activeSubTab}`}
+          >
+            {activeSubTab === 'monitoring' ? (
+              <MonitoringView />
+            ) : activeSubTab === 'statistics' ? (
+              <StatisticsView />
+            ) : (
+              <DailyReportView />
+            )}
+          </div>
         </FadeIn>
       </AnimatePresence>
       <RotatingFooterHint />