とりあえず仕様を見てみます。 This property describes the foreground color of an element’s text content. Cascading Style Sheets Level 2 Revision 1 (CSS 2.1) Specification - 14.1 Foreground color: the 'color' propertyThis property describes the foreground color of an element's text content. In addition it is used to provide a potential indirect value (currentColor) for any other properties that accept color value