Django~static files

such as images, JavaScript, or CSS

https://docs.djangoproject.com/en/1.9/howto/static-files/

django.contrib.staticfiles

1.polls/static/polls/style.css

2.polls/templates/polls/index.html

Adding a background-image

polls/static/polls/images/background.gif.

body {

    background: white url("images/background.gif") no-repeat right bottom;

}