Express static css files is not load in handlebars

Question

App.js -> main js express file so I make like this

const express = require('express');
const app= express();
app.use(express.static('public'))

Main Layou -> main Layout handlebar file , i add a link tag to style like this (main.hbs)

<link rel='stylesheet' href='/style.css'>

Files And Folder Structure I have other hbs files in views , but when I add style link to separate file it does work but it not working when in main layout hbs

project-root/
│
├── app.js
│
├── public/
│   └── style.css
│
├── routes/
│   └── routes.js
│
└── views/
    ├── layouts/
    │   └── main.hbs
    ├── create.hbs
    ├── edit.hbs

I tried like this in my server : localhost/ cssfilename

It displays the style code

Also in style.css i added body background colour: black and input types width :250px