syn cluster sassCssProperties contains=cssFontProp,cssFontDescriptorProp,cssColorProp,cssTextProp,cssBoxProp,cssGeneratedContentProp,cssPagingProp,cssUIProp,cssRenderProp,cssAuralProp,cssTableProp
syn cluster sassCssAttributes contains=css.*Attr,scssComment,cssValue.*,cssColor,cssURL,sassDefault,cssImportant,cssError,cssStringQ,cssStringQQ,cssFunction,cssUnicodeEscape,cssRenderProp
syn region sassDefinition matchgroup=cssBraces start="{" end="}" contains=TOP
syn match sassProperty "\%([{};]\s*\|^\)\@<=\%([[:alnum:]-]\|#{[^{}]*}\)\+:" contains=css.*Prop skipwhite nextgroup=sassCssAttribute contained containedin=sassDefinition
syn match sassProperty "^\s*\zs\s\%(\%([[:alnum:]-]\|#{[^{}]*}\)\+:\|:[[:alnum:]-]\+\)"hs=s+1 contains=css.*Prop skipwhite nextgroup=sassCssAttribute
syn match sassProperty "^\s*\zs\s\%(:\=[[:alnum:]-]\+\s*=\)"hs=s+1 contains=css.*Prop skipwhite nextgroup=sassCssAttribute
syn match sassCssAttribute +\%("\%([^"]\|\\"\)*"\|'\%([^']\|\\'\)*'\|#{[^{}]*}\|[^{};]\)*+ contained contains=@sassCssAttributes,sassVariable,sassFunction,sassInterpolation
syn match sassDefault "!default\>" contained
syn match sassVariable "!\%(important\>\|default\>\)\@![[:alnum:]_-]\+"
syn match sassVariable "$[[:alnum:]_-]\+"
syn match sassVariableAssignment "\%([!$][[:alnum:]_-]\+\s*\)\@<=\%(||\)\==" nextgroup=sassCssAttribute skipwhite
syn match sassVariableAssignment "\%([!$][[:alnum:]_-]\+\s*\)\@<=:" nextgroup=sassCssAttribute skipwhite
syn match sassFunction "\<\%(rgb\|rgba\|red\|green\|blue\|mix\)\>(\@=" contained
syn match sassFunction "\<\%(hsl\|hsla\|hue\|saturation\|lightness\|adjust-hue\|lighten\|darken\|saturate\|desaturate\|grayscale\|complement\)\>(\@=" contained
syn match sassFunction "\<\%(alpha\|opacity\|rgba\|opacify\|fade-in\|transparentize\|fade-out\)\>(\@=" contained
syn match sassFunction "\<\%(unquote\|quote\)\>(\@=" contained
syn match sassFunction "\<\%(percentage\|round\|ceil\|floor\|abs\)\>(\@=" contained
syn match sassFunction "\<\%(type-of\|unit\|unitless\|comparable\)\>(\@=" contained
syn region sassInterpolation matchgroup=sassInterpolationDelimiter start="#{" end="}" contains=@sassCssAttributes,sassVariable,sassFunction containedin=cssStringQ,cssStringQQ,sassProperty
syn match sassMixinName "[[:alnum:]_-]\+" contained nextgroup=sassCssAttribute
syn match sassMixin "^=" nextgroup=sassMixinName
syn match sassMixin "\%([{};]\s*\|^\s*\)\@<=@mixin" nextgroup=sassMixinName skipwhite
syn match sassMixing "^\s\+\zs+" nextgroup=sassMixinName
syn match sassMixing "\%([{};]\s*\|^\s*\)\@<=@include" nextgroup=sassMixinName skipwhite
syn match sassExtend "\%([{};]\s*\|^\s*\)\@<=@extend"
syn match sassEscape "^\s*\zs\\"
syn match sassIdChar "#[[:alnum:]_-]\@=" nextgroup=sassId
syn match sassId "[[:alnum:]_-]\+" contained
syn match sassClassChar "\.[[:alnum:]_-]\@=" nextgroup=sassClass
syn match sassClass "[[:alnum:]_-]\+" contained
syn match sassAmpersand "&"
" TODO: Attribute namespaces
" TODO: Arithmetic (including strings and concatenation)
syn region sassInclude start="@import" end=";\|$" contains=scssComment,cssURL,cssUnicodeEscape,cssMediaType
syn region sassDebugLine end=";\|$" matchgroup=sassDebug start="@debug\>" contains=@sassCssAttributes,sassVariable,sassFunction
syn region sassWarnLine end=";\|$" matchgroup=sassWarn start="@warn\>" contains=@sassCssAttributes,sassVariable,sassFunction
syn region sassControlLine matchgroup=sassControl start="@\%(if\|else\%(\s\+if\)\=\|while\|for\)\>" end="[{};]\@=\|$" contains=sassFor,@sassCssAttributes,sassVariable,sassFunction
syn keyword sassFor from to through contained
syn keyword sassTodo FIXME NOTE TODO OPTIMIZE XXX contained
syn region sassComment start="^\z(\s*\)//" end="^\%(\z1 \)\@!" contains=sassTodo,@Spell
syn region sassCssComment start="^\z(\s*\)/\*" end="^\%(\z1 \)\@!" contains=sassTodo,@Spell