To remove all shading from text in a document, select all the text and press Ctrl+Q (resets paragrah formatting to that of the underlying style) and then press Ctrl+SpaceBar (resets character formatting to that of the underlying paragraph style). To remove
highlighting, click the arrow on the Text Highlight Color button and choose No Color.
Alternatively, you can run the following macro:
Sub ClearAllShadingFromDoc()
'Macro created by Stefan Blom, MVP, September 2016
ActiveDocument.Content.HighlightColorIndex = wdNoHighlight
With ActiveDocument.Content.ParagraphFormat.Shading
.Texture = wdTextureNone
.ForegroundPatternColor = wdColorAutomatic
.BackgroundPatternColor = wdColorAutomatic
End With
With ActiveDocument.Content.Font.Shading
.Texture = wdTextureNone
.ForegroundPatternColor = wdColorAutomatic
.BackgroundPatternColor = wdColorAutomatic
End With
End Sub
For assistance, see http://www.gmayor.com/installing_macro.htm.
If the macro helps, the next step is to update your styles to match the selection.