anchor.diff:      (:html
        (:meta :charset "utf-8")
        (:meta :property "og:url" :content "http://flightschool.solarsails.info/reflect.html")
  -     (:meta :property "og:title" :content "Sunlight Reflected by a Sail")
  +     (:meta :property "og:title" :content "Sunlight Reflected by a Solar Sail")
        (:meta :property "og:description" :content "Lesson 4: Learn how to reflect light off of a solar sail.")
        (:meta :property "og:image" :content "http://flightschool.solarsails.info/img/reflect_image.png")
        (:meta :property "og:description" :content "Lesson 4: Learn how to reflect light off of a solar sail.")
        (:meta :property "og:site_name" :content "Solar Sail Flight School")
  -     (:title "Sunlight Reflected by a Sail")
  +     (:title "Sunlight Reflected by a Solar Sail")
        (:link :href "sail.css" :rel "stylesheet")
        (:script :src "js/three.min.js")
        (:script :src "js/jquery-1.11.1.min.js")
  
positive.code:      (:script :src "js/lib.js")
       (:body
        (:div :id "info"
  	    (:h1 "Sunlight Reflected by a Sail")
  	    (:ul
  	     (:li "Light reflects off of the mirrored sail at the same angle that it hit it.")
  	     (:li "The yellow boxes show the light absorbed and reflected by the sail.")
  
negative.code: 			(:li "Up and down arrows to tilt")
  			(:li "Right and left arrows to rotate")))))
        (:div :id "nav"
  	    (:h2 (:a :href "http://www.patreon.com/bld" "Next: Help develop it at Patreon"))
  	    (:h2 (:a :href "/absorb.html" "Previous: Sunlight Absorbed by a Sail"))
  	    (:h2 (:a :href "/index.html" "Home")))
        (:img :id "up" :src "img/arrow_up.svg")
  