" Add match for GitHub style check boxes
syn match markdownCheckboxDelimiter '[\[\]]' contained
syn match markdownCheckboxTick 'x' contained
syn match markdownCheckbox '\s*\*\s\[\(x\|\s\)\]\s' contains=markdownCheckboxDelimiter,markdownCheckboxTick,markdownListMarker

hi link markdownCode Special
hi link markdownCodeDelimiter PreProc
hi link markdownHeadingDelimiter Statement
hi link markdownLinkDelimiter PreProc
hi link markdownLinkTextDelimiter PreProc
hi link markdownUrl Include
hi link markdownCheckboxTick Statement
hi link markdownCheckboxDelimiter PreProc