[Django]-Django not loading CSS?

The problem comes from 2 areas.

1. wrong document_root variable passed
2. not using template tags in html

1.
Defining site_media variable in urls.py file is discouraged as it does not adhere to DRY principle. It should be held as a variable in your settings.py file so other modules may import if needed.
In your settings.py file, add the following line:

import os.path
SITE_MEDIA_ROOT = os.path.join(
    os.path.dirname(__file__), 'myApp/', 'static/', 'site_media' #this should be the correct path instead
)

Replace your urls.py file with this:

from myApp import settings

urlpatterns = patterns('',
url(r'^site_media/(?P<path>.*)$', 'django.views.static.serve',
{ 'document_root': settings.SITE_MEDIA_ROOT }),
)

2.You should use django template tags to get the css file. In your base template, add this line above the head tag:

{% load static %}

Then replace:

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

with:

<link rel='stylesheet' type='text/css' href="{% static 'site_media/css/style.css' %}" />

After which it should work.