How to apply CSS to musical accidentals?

This is in a small html file:

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">...<p>html code: C&#9839; C&#9837; C&#9838; or paste: sharp (C♯), flat (C♭), natural (C♮)</p>

In FF on PC both ways look fine. But in Android and Safari the Flat and Natural are badly kerned in all fonts I tried. To debug this I removed all font-family specifications and added color in CSS:

p {color:red;}

In FF/PC everything is red but elsewhere the Sharp is red but Flat and Natural stay black.

1. Does this mean that in Android and Safari #9837 #9838 do not render in the default font but #9839 does so?
2. What font should I use to render the three accidentals on the three platforms?

(NB I'm aware of all kinds of sofisticated solutions (html5, xml) but I have allready automated the writing of the html's so a pure CSS solution is welcomed)

(NB2 in the newest version of Safari all three are red but the bad kerning stays the same)