[skip ci] fix(module/web/pages/source): import ElementPlus darkmode css var

modules/web/src/pages/source/main.js

@@ -2,5 +2,6 @@ import { createApp } from "vue";
 import App from "@/App.vue";
 import sourceRouter from "@/router/sourceRouter";
 import store from "@/store";
+import "element-plus/theme-chalk/dark/css-vars.css";
 
 createApp(App).use(store).use(sourceRouter).mount("#app");