Changing furigana in Word 2011 for Mac

There is no straight way of adjusting the size of all the furiganas in a document. But there is a way.

Let's say you have the following text with furigana.

漢字(かんじ)のふりがなを調整(ちょうせい)します。

Press Option+F9, or go into Preferences > View and check the Show > "Field code" box. Then you'll see the text transformed to:

{ eq * jc2 * "Font:ＭＳ 明朝" * hps12 \o\ad(\s\up 11(かんじ),漢字)}のふりがなを{ eq * jc2 * "Font:ＭＳ 明朝" * hps12 \o\ad(\s\up 11(ちょうせい),調整)}します。

This is how Word stores markup information for each furigana. What we're interested in is the hps12 bit: it specifies the size of the furigana. If you replace it with hps20:

{ eq * jc2 * "Font:ＭＳ 明朝" * hps20 \o\ad(\s\up 11(かんじ),漢字)}のふりがなを{ eq * jc2 * "Font:ＭＳ 明朝" * hps20 \o\ad(\s\up 11(ちょうせい),調整)}します。

and press Option+F9 again:

漢字(かんじ)のふりがなを調整(ちょうせい)します。

the size of the furigana should be adjusted. As far as I've experimented, hps12 corresponds to a font size of 6pt, and hps20 to 10pt.

Note: on Windows, the shortcut for toggling field code is Alt+F9.