title: "GET /static/css%5Cmain.css HTTP/1.1" 404 -
body: <blockquote>
  <p>I am making a web page with python and flask, but when I want to use css the console sends me this error and the changes in the html are not applied.  this is the .py file.</p>
  </blockquote>
  <pre><code>from flask import Flask, render_template
  
  app=Flask(__name__)
  
  @app.route(&quot;/&quot;)
  def home():
     return render_template('home.html')
  
  
  @app.route(&quot;/about&quot;)
  def about():
     return render_template('about.html')
  
  if __name__ == &quot;__main__&quot;:
     app.run(debug=True)
  </code></pre>
  <blockquote>
  <p>//this is the home.html file //</p>
  </blockquote>
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html lang=&quot;es&quot;&gt;
  &lt;head&gt;
    &lt;meta charset=&quot;UTF-8&quot;&gt;
    &lt;meta http-equiv=&quot;X-UA-Compatible&quot; content=&quot;IE=edge&quot;&gt;
    &lt;meta name=&quot;viewport&quot; content=&quot;width=device-width, initial- 
     scale=1.0&quot;&gt;
    &lt;title&gt;Document with python&lt;/title&gt;
    &lt;link rel=&quot;stylesheet&quot; type=&quot;text/css&quot; href=&quot;{{ 
       url_for('static',filename='css\main.css') }}&quot;&gt;
    &lt;/head&gt;
    &lt;body&gt;
       &lt;h1&gt;hola mundo, como esta&lt;/h1&gt;
    &lt;/body&gt;
    &lt;/html&gt;
  </code></pre>
  <blockquote>
  <p>//this is the main.css file //</p>
  </blockquote>
  <pre><code>body {
  background: chartreuse;
  font-family: 'Courier New', Courier, monospace;
  </code></pre>
  <p>}</p>
  <blockquote>
  <p>edit: already change   css \ main.css   to    css / main.css</p>
  </blockquote>