The problem of not loading css and js in the template directory

[irvaniamirali]

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Example Code

from fastapi import FastAPI
from fastapi.staticfiles import StaticFiles
from fastapi.templating import Jinja2Templates

app = FastAPI()
templates = Jinja2Templates(directory='app/templates')
app.mount("/app/templates", StaticFiles(directory="app/templates"), name="not_found_page")

@app.exception_handler(404)
async def custom_404_handler(request, __):
    return templates.TemplateResponse(
        'index.html', {
            'request': request
        }
    )

Description

Hi
I was looking for a 404 page for templates in my app
My program is in Python language and powerful fastapi framework
But I have a problem with the templates
My problem is that the css and js files are not loaded inside the index.html file
I would really appreciate it if you could help me with this problem
Thanks

Operating System

Linux

Operating System Details

No response

FastAPI Version

0.109.2

Pydantic Version

2.6.1

Python Version

3.12.0

Additional Context

No response