fontawseme link css code example
Example 1: font awesome cdn
<link rel="stylesheet" type="text/css" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.4.0/css/font-awesome.min.css">
Example 2: fontawesome cdn
gem 'font-awesome-sass'
<link rel="stylesheet" type="text/css" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.4.0/css/font-awesome.min.css">
gem 'font-awesome-sass'