anchor.diff:  color.
   
   <% example(autogen_css: false) do %>
  -// This will produce a color with hue 180deg.
  -@debug adjust-hue(hsl(120deg, 30%, 90%), 60deg); // #deeded
  -
  -// This will produce a color with hue 60deg.
  -@debug adjust-hue(hsl(120deg, 30%, 90%), -60deg); // #ededde
  -
  -// #036 has hue 210deg, so the result has hue 255deg.
  +// Hue 222deg becomes 282deg.
  +@debug adjust-hue(#6b717f, 60deg); // #796b7f
  +
  +// Hue 164deg becomes 104deg.
  +@debug adjust-hue(#d2e1dd, -60deg); // #d6e1d2
  +
  +// Hue 210deg becomes 255deg.
   @debug adjust-hue(#036, 45); // #1a0066
   ===
  -// This will produce a color with hue 180deg.
  -@debug adjust-hue(hsl(120deg, 30%, 90%), 60deg)  // #deeded
  -
  -// This will produce a color with hue 60deg.
  -@debug adjust-hue(hsl(120deg, 30%, 90%), -60deg)  // #ededde
  -
  -// #036 has hue 210deg, so the result has hue 255deg.
  +// Hue 222deg becomes 282deg.
  +@debug adjust-hue(#6b717f, 60deg)  // #796b7f
  +
  +// Hue 164deg becomes 104deg.
  +@debug adjust-hue(#d2e1dd, -60deg)  // #d6e1d2
  +
  +// Hue 210deg becomes 255deg.
   @debug adjust-hue(#036, 45)  // #1a0066
   <% end %>
   <% end %>
   
  -<% function 'alpha($color)', 'opacity($color)', returns: 'color' do %>
  +
  +<% function 'alpha($color)', 'opacity($color)', returns: 'number' do %>
   Returns the alpha channel of `$color` as a number between 0 and 1.
   
   As a special case, this supports the Internet Explorer syntax
  
positive.code: 
  [unquoted string]: ../documentation/values/strings#unquoted
  
  <% example(autogen_css) do %>
  @debug alpha(#e1d7d2); // 1
  @debug alpha(rgb(210, 225, 221, 0.4)); // 0.4
  @debug alpha(opacity=20); // alpha(opacity=20)
  ===
  @debug alpha(#e1d7d2)  // 1
  @debug alpha(rgb(210, 225, 221, 0.4))  // 0.4
  @debug alpha(opacity=20)  // alpha(opacity=20)
  <% end %>
  <% end %>
  
  alpha($color) / opacity($color) : Gets the alpha component (opacity) of a color.
  blue($color) : Gets the blue component of a color.
  change-color($color, [$red], [$green], [$blue], [$hue], [$saturation], [$lightness], [$alpha]) : Changes one or more properties of a color.
  complement($color) : Returns the complement of a color.
  darken($color, $amount) : Makes a color darker.
  desaturate($color, $amount) : Makes a color less saturated.
  grayscale($color) : Converts a color to grayscale.
  green($color) : Gets the green component of a color.
  
  <% function 'hsl($hue, $saturation, $lightness)', returns: 'color' do %>
  Returns a color with the given [hue, saturation, and lightness][] and the given
  
negative.code: @debug hsl(34, 35%, 92%) // #f2ece4
  <% end %>
  <% end %>
  
  
  <% function 'hsla($hue, $saturation, $lightness, $alpha)', returns: 'color' do %>
  <% impl_status dart: true, libsass: false, ruby: '3.7.0' do %>
  