" Customize highlight groups
hi link markdownCode Special
hi link markdownCodeDelimiter PreProc
hi link markdownHeadingDelimiter PreProc
hi link markdownLinkDelimiter PreProc
hi link markdownLinkTextDelimiter PreProc
hi link markdownUrl Include

" Add match for GitHub style check boxes
syn match markdownCheckboxTick '\[\zsx\ze\]' contained
syn match markdownCheckboxDelimiter '\[[ x]\]' contained contains=markdownCheckboxTick
syn match markdownCheckbox '\s*\* \[[ x]\] ' contains=markdownCheckboxDelimiter,markdownListMarker
syn region markdownCheckboxDone start='\s*\* \ze\[x\] ' keepend end='\ze\(\n^\s*\*\|\n^\s*\n\)' contains=markdownCheckbox

hi link markdownCheckboxTick markdownListMarker
hi link markdownCheckboxDelimiter PreProc
hi link markdownCheckboxDone Comment

" Add match for TODO
syn match markdownTodo 'TODO'

hi link markdownTodo Todo
syn cluster markdownInline add=markdownTodo