diff --git a/clay.cabal b/clay.cabal
--- a/clay.cabal
+++ b/clay.cabal
@@ -1,5 +1,5 @@
 Name:     clay
-Version:  0.1.1
+Version:  0.2
 Synopsis: CSS preprocessor as embedded Haskell.
 Description:
   Clay is a CSS preprocessor like LESS and Sass, but implemented as an embedded
@@ -7,17 +7,21 @@
   and style rules are first class Haskell functions, which makes reuse and
   composability easy.
   .
-  The project is described on <http://sebastiaanvisser.github.com/clay>.
+  The project is described on <http://fvisser.nl/clay>.
   .
   The API documentation can be found in the top level module "Clay".
   .
-  > 0.1 -> 0.1.1
-  >   - Fixed bug in visibility property.
-  >   Thanks to Conrad Indiono for the pull request.
+  > 0.1.1 -> 0.2
+  >   - Rotate takes only one argument.
+  >   - Added opacity property.
+  >   - Print Clay banner in CSS comments by default.
+  >   - Fixed bug in font-family rendering (Firefox only).
+  >   - Added outline related properties.
+  >   - Fixed bug in monospace font family.
 
 Author:        Sebastiaan Visser
 Maintainer:    Sebastiaan Visser <code@fvisser.nl>
-Homepage:      http://sebastiaanvisser.github.com/clay
+Homepage:      http://fvisser.nl/clay
 Bug-Reports:   http://github.com/sebastiaanvisser/clay/issues
 
 License:       BSD3
diff --git a/src/Clay/Border.hs b/src/Clay/Border.hs
--- a/src/Clay/Border.hs
+++ b/src/Clay/Border.hs
@@ -1,9 +1,9 @@
 {-# LANGUAGE OverloadedStrings, GeneralizedNewtypeDeriving #-}
 module Clay.Border
 (
--- * Stroke type.
+-- * Stroke type, used for border-style and outline-style.
   Stroke
-, solid, dotted, dashed, double, wavy
+, solid, dotted, dashed, double, wavy, groove, ridge, inset, outset
 
 -- * Border properties.
 
@@ -12,6 +12,14 @@
 , borderStyle, borderLeftStyle, borderRightStyle, borderTopStyle, borderBottomStyle
 , borderWidth, borderLeftWidth, borderRightWidth, borderTopWidth, borderBottomWidth
 
+-- * Outline properties.
+
+, outline, outlineTop, outlineLeft, outlineBottom, outlineRight
+, outlineColor, outlineLeftColor, outlineRightColor, outlineTopColor, outlineBottomColor
+, outlineStyle, outlineLeftStyle, outlineRightStyle, outlineTopStyle, outlineBottomStyle
+, outlineWidth, outlineLeftWidth, outlineRightWidth, outlineTopWidth, outlineBottomWidth
+, outlineOffset
+
 -- * Border radius.
 
 , borderRadius
@@ -29,14 +37,20 @@
 newtype Stroke = Stroke Value
   deriving (Val, Other, Inherit, Auto, None)
 
-solid, dotted, dashed, double, wavy :: Stroke
+solid, dotted, dashed, double, wavy, groove, ridge, inset, outset :: Stroke
 
 solid  = Stroke "solid"
 dotted = Stroke "dotted"
 dashed = Stroke "dashed"
 double = Stroke "double"
-wavy   = Stroke "Wavu"
+wavy   = Stroke "wavy"
+groove = Stroke "groove"
+ridge  = Stroke "ridge"
+inset  = Stroke "inset"
+outset = Stroke "outset"
 
+-------------------------------------------------------------------------------
+
 border, borderTop, borderLeft, borderBottom, borderRight :: Stroke -> Size Abs -> Color -> Css
 
 border        a b c = key "border"        (a ! b ! c)
@@ -68,6 +82,43 @@
 borderRightWidth  = key "border-right-width"
 borderTopWidth    = key "border-top-width"
 borderBottomWidth = key "border-bottom-width"
+
+-------------------------------------------------------------------------------
+
+outline, outlineTop, outlineLeft, outlineBottom, outlineRight :: Stroke -> Size Abs -> Color -> Css
+
+outline        a b c = key "outline"        (a ! b ! c)
+outlineTop     a b c = key "outline-top"    (a ! b ! c)
+outlineLeft    a b c = key "outline-left"   (a ! b ! c)
+outlineBottom  a b c = key "outline-bottom" (a ! b ! c)
+outlineRight   a b c = key "outline-right"  (a ! b ! c)
+
+outlineColor, outlineLeftColor, outlineRightColor, outlineTopColor, outlineBottomColor :: Color -> Css
+
+outlineColor       = key "outline-color"
+outlineLeftColor   = key "outline-left-color"
+outlineRightColor  = key "outline-right-color"
+outlineTopColor    = key "outline-top-color"
+outlineBottomColor = key "outline-bottom-color"
+
+outlineStyle, outlineLeftStyle, outlineRightStyle, outlineTopStyle, outlineBottomStyle :: Stroke -> Css
+
+outlineStyle       = key "outline-style"
+outlineLeftStyle   = key "outline-left-style"
+outlineRightStyle  = key "outline-right-style"
+outlineTopStyle    = key "outline-top-style"
+outlineBottomStyle = key "outline-bottom-style"
+
+outlineWidth, outlineLeftWidth, outlineRightWidth, outlineTopWidth, outlineBottomWidth :: Size Abs -> Css
+
+outlineWidth       = key "outline-width"
+outlineLeftWidth   = key "outline-left-width"
+outlineRightWidth  = key "outline-right-width"
+outlineTopWidth    = key "outline-top-width"
+outlineBottomWidth = key "outline-bottom-width"
+
+outlineOffset :: Size Abs -> Css
+outlineOffset = key "outline-offset"
 
 -------------------------------------------------------------------------------
 
diff --git a/src/Clay/Display.hs b/src/Clay/Display.hs
--- a/src/Clay/Display.hs
+++ b/src/Clay/Display.hs
@@ -43,6 +43,10 @@
 , clip
 , rect
 
+-- * Opacity.
+
+, opacity
+
 -- * Z-index.
 
 , zIndex
@@ -173,6 +177,9 @@
 rect t r b l = Clip (mconcat ["rect(", value t, ",", value r, ",", value b, ",", value l, ")"])
 
 -------------------------------------------------------------------------------
+
+opacity :: Double -> Css
+opacity = key "opacity"
 
 zIndex :: Integer -> Css
 zIndex i = key "z-index" (fromString (show i) :: Value)
diff --git a/src/Clay/Font.hs b/src/Clay/Font.hs
--- a/src/Clay/Font.hs
+++ b/src/Clay/Font.hs
@@ -118,7 +118,7 @@
 -------------------------------------------------------------------------------
 
 fontFamily :: [Text] -> [Text] -> Css
-fontFamily a b = key "font-family" (value (Literal <$> a) ! value b)
+fontFamily a b = key "font-family" (value (Literal <$> a) <> if null b then "" else (", " <> value b))
 
 sansSerif :: Text
 sansSerif = "sans-serif"
@@ -127,7 +127,7 @@
 serif = "serif"
 
 monospace :: Text
-monospace = "fixed"
+monospace = "monospace"
 
 -------------------------------------------------------------------------------
 
diff --git a/src/Clay/Render.hs b/src/Clay/Render.hs
--- a/src/Clay/Render.hs
+++ b/src/Clay/Render.hs
@@ -35,17 +35,18 @@
   , sep         :: Builder
   , warn        :: Bool
   , align       :: Bool
+  , banner      :: Bool
   }
 
 -- | Configuration to print to a pretty human readable CSS output.
 
 pretty :: Config
-pretty = Config "  " "\n" " " True True
+pretty = Config "  " "\n" " " True True True
 
 -- | Configuration to print to a compacted unreadable CSS output.
 
 compact :: Config
-compact = Config "" "" "" False False
+compact = Config "" "" "" False False True
 
 -- | Render to CSS using the default configuration (`pretty`) and directly
 -- print to the standard output.
@@ -64,10 +65,17 @@
 
 renderWith :: Config -> [App] -> Css -> Lazy.Text
 renderWith cfg top (S c)
-  = toLazyText
+  = renderBanner cfg
+  . toLazyText
   . rules cfg top
   . execWriter
   $ c
+
+renderBanner :: Config -> Lazy.Text -> Lazy.Text
+renderBanner cfg =
+  if banner cfg
+  then (<> "\n/* Generated with Clay, http://fvisser.nl/clay */")
+  else id
 
 rules :: Config -> [App] -> [Rule] -> Builder
 rules cfg sel rs = mconcat
diff --git a/src/Clay/Transform.hs b/src/Clay/Transform.hs
--- a/src/Clay/Transform.hs
+++ b/src/Clay/Transform.hs
@@ -72,8 +72,8 @@
 
 -------------------------------------------------------------------------------
 
-rotate :: Angle a -> Angle a -> Transformation
-rotate x y = Transformation ("rotate(" <> value [x, y] <> ")")
+rotate :: Angle a -> Transformation
+rotate x = Transformation ("rotate(" <> value x <> ")")
 
 rotateX, rotateY, rotateZ :: Angle a -> Transformation