main.py

from flask import Flask, render_template

app = Flask(__name__,
            static_url_path='/static',
            static_folder='static',
            template_folder='templates')

@app.route("/")
def shadow():
    return render_template("index.html")

@app.route("/download")
def download():
    return render_template("download.html")

if __name__ == "__main__":
    app.run(host='localhost', port=5050, debug=True)