- use spaces instead of tabs
- the unit of indentation is two spaces
- no trailing whitespaces
- each commit should must have a comment
- the first line should start with a capital letter
- the total line length should be no more than 80 characters
- the body might provide an extra commit message
- specify dependency versions in your Gemfile
[Ruby] (https://github.com/styleguide/ruby)
- take advantage of light-weight classes and ids
div class='class-name'
img id='my-image'
.class-name
img#my-img
.this-is-a-reasonable-class-name
.ThisIsNotOK
.this_is_also_wrong