gorilla/mux在構建簡單的 API 時，我遇到了 Go 和路由器的以下問題。我確信這是我臉上常見的愚蠢錯誤，但我看不到它。簡化的項目結構|--main.go||--public/--index.html|        |--image.png||--img/--img1.jpg|     |--img2.jpg|     |--...|...main.gopackage mainimport (    "net/http"    "github.com/gorilla/mux")var Router = mux.NewRouter()func InitRouter() {    customers := Router.PathPrefix("/customers").Subrouter()    customers.HandleFunc("/all", getAllCustomers).Methods("GET")    customers.HandleFunc("/{customerId}", getCustomer).Methods("GET")    // ...    // Registering whatever middleware    customers.Use(middlewareFunc)    users := Router.PathPrefix("/users").Subrouter()    users.HandleFunc("/register", registerUser).Methods("POST")    users.HandleFunc("/login", loginUser).Methods("POST")    // ...    // Static files (customer pictures)    var dir string    flag.StringVar(&dir, "images", "./img/", "Directory to serve the images")    Router.PathPrefix("/static/").Handler(http.StripPrefix("/static/", http.FileServer(http.Dir(dir))))    var publicDir string    flag.StringVar(&publicDir, "public", "./public/", "Directory to serve the homepage")    Router.Handle("/", http.StripPrefix("/", http.FileServer(http.Dir(publicDir))))}func main() {    InitRouter()    // Other omitted configuration    server := &http.Server{        Handler: Router,        Addr:    ":" + port,        // Adding timeouts        WriteTimeout: 15 * time.Second,        ReadTimeout:  15 * time.Second,    }    err := server.ListenAndServe()    // ...}子路由工作正常，中間件和所有。img如果我去下面的圖像是正確的localhost:5000/static/img1.png。問題是，將localhost:5000服務于index.html駐留的public，但隨后localhost:5000/image.png是 a 404 not found。這里發生了什么？