hi!, i new here, am try to deploy a simple runtine in golang , it's a simple web app, so i try deploy but don't work, this is my "site" https://portalcomunidadretro.up.railway.app/, my code is :

package main

import (
"fmt"
"net/http"
)

func main() {
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
fmt.Println("here!")
http.ServeFile(w, r, "static/index.html")
})
http.HandleFunc("/saludo", func(w http.ResponseWriter, r *http.Request) {
fmt.Println("Buscando index!!")
fmt.Fprintf(w, "All OK!!")

})
fmt.Println("Servidor escuchando en el puerto :80, sin novedades")
http.ListenAndServe(":80", nil)

}

according to railway, everything is ok and ready to work, but when I enter the url, it tells me that there is an error, i need help