refactor(滚动锁定): 重构页面滚动锁定逻辑

- 使用全局计数器解决多组件并发锁定竞态问题
- 将 HTML class 注入逻辑移至 composable 中统一管理
- 优化锁定状态更新逻辑，避免重复操作
- 移除不再需要的计算属性和导入

app/app.vue

@@ -1,7 +1,6 @@
 <script setup lang="ts">
 import { useHead, useSeoMeta } from '#imports'
 import { useI18n } from 'vue-i18n'
-import { computed } from 'vue'
 
 const { t } = useI18n()
 

app/components/home/HomeHero.vue

@@ -94,7 +94,7 @@ onBeforeUnmount(() => {
   cleanupHeroScroll?.()
 })
 
-defineExpose({ heroStageRef, heroRef, play })
+defineExpose({ play })
 </script>
 
 <template>

app/composables/usePageScrollLock.ts

@@ -1,50 +1,55 @@
-import { onMounted, onBeforeUnmount, watch, type Ref } from 'vue'
-import { useNuxtApp } from '#app'
+import { onBeforeUnmount, watch, type Ref, isRef, unref, computed } from 'vue'
+import { useNuxtApp, useHead } from '#imports'
 import type Lenis from 'lenis'
-import { useAppStore } from '~/stores/app'
+
+// 全局模块级变量，用于记录锁定请求的次数，解决多组件并发锁定的竞态问题
+let lenisLockCount = 0
 
 export const usePageScrollLock = (isLocked: Ref<boolean> | boolean) => {
   const { $lenis } = useNuxtApp() as ReturnType<typeof useNuxtApp> & { $lenis?: Lenis }
   
-  const lockScroll = () => {
-    if (import.meta.client) {
-      document.documentElement.classList.add('is-home-intro-active')
-      $lenis?.scrollTo(0, { immediate: true })
-      $lenis?.stop()
+  // SSR 和 CSR 都支持：自动将 class 注入到 HTML 标签上
+  useHead({
+    htmlAttrs: {
+      class: computed(() => unref(isLocked) ? 'is-home-intro-active' : undefined)
     }
-  }
-
-  const unlockScroll = () => {
-    if (import.meta.client) {
-      document.documentElement.classList.remove('is-home-intro-active')
-      $lenis?.start()
-    }
-  }
-
-  // If passed a boolean, lock immediately and unlock on unmount
-  if (typeof isLocked === 'boolean') {
-    if (isLocked) {
-      onMounted(() => {
-        lockScroll()
   })
-      onBeforeUnmount(() => {
-        unlockScroll()
-      })
-    }
-  } else {
-    // If passed a ref, watch its value
-    watch(isLocked, (locked) => {
+
+  let currentlyLocked = false
+
+  const updateLock = (locked: boolean) => {
+    // 防止重复触发相同状态
+    if (locked === currentlyLocked) return
+    currentlyLocked = locked
+
+    // Lenis 控制仅在客户端有效
+    if (import.meta.client && $lenis) {
       if (locked) {
-        lockScroll()
-      } else {
-        unlockScroll()
+        lenisLockCount++
+        // 只有第一个锁请求时，才真正停止 Lenis 并滚动到顶部
+        if (lenisLockCount === 1) {
+          $lenis.scrollTo(0, { immediate: true })
+          $lenis.stop()
+        }
+      } else {
+        lenisLockCount = Math.max(0, lenisLockCount - 1)
+        // 只有当所有锁请求都释放时，才重新启动 Lenis
+        if (lenisLockCount === 0) {
+          $lenis.start()
+        }
+      }
+    }
   }
-    }, { immediate: true })
 
+  // 监听 Ref 变化，或立即处理 boolean 值
+  if (isRef(isLocked)) {
+    watch(isLocked, updateLock, { immediate: true })
+  } else {
+    updateLock(isLocked)
+  }
+
+  // 组件卸载时安全释放当前持有的锁
   onBeforeUnmount(() => {
-      unlockScroll()
+    updateLock(false)
   })
 }
-
-  return { lockScroll, unlockScroll }
-}

app/pages/index.vue

@@ -20,13 +20,6 @@ if (!userStore.isLoggedIn) {
   userStore.loadDemoUser()
 }
 
-// 让首屏入场的锁滚动在 SSR/首帧就生效，避免等 onMounted 才隐藏滚动条。
-useHead({
-  htmlAttrs: {
-    class: computed(() => (isIntroActive.value ? 'is-home-intro-active' : undefined)),
-  },
-})
-
 // 使用组合式函数管理 Lenis 滚动锁定
 usePageScrollLock(isIntroActive)