How to correctly use static files in bottle templates?

I am able to download the css file mentioned in my template, but the page renders as if the browser was unable to access the stylesheet.

Here is my directory structure:

/myapp
     myapp.py
     bottle.py
     views
         template.tpl
     styles
         main.css
 

here is the relevant line from the template:

<link rel="stylesheet" type="text/css" href="main.css" />
 

and I have this in myapp.py

from bottle import route, run, debug, template, error, static_file
 
 
 @route('/styles/<filename>')
 def send_css(filename):
     return static_file(filename, root='styles')
 
 @route('/')
 def index():
     return template('template')
 
 debug(True)
 run(host='localhost', port=8080, reloader=True)
 

---