refactor: 重构主题色配置，多标签配置化处理

src/views/error-page/404.vue

@@ -2,7 +2,7 @@
   <div class="page-404">
     <n-result status="404" description="抱歉，您访问的页面不存在。">
       <template #icon>
-        <img src="@/assets/images/404.png" width="500" />
+        <img src="@/assets/images/404.png" width="300" />
       </template>
       <template #footer>
         <n-button strong secondary type="primary" @click="replace('/')">返回首页</n-button>
@@ -18,10 +18,14 @@ const { replace } = useRouter()
 
 <style lang="scss" scoped>
 .page-404 {
-  height: 100%;
-  min-height: calc(100vh - 60px);
   display: flex;
   align-items: center;
   justify-content: center;
+
+  position: absolute;
+  top: 50px;
+  bottom: 50px;
+  left: 0;
+  right: 0;
 }
 </style>