This is a know gmail 'issue'. You will need to overrule the default gmail stylesheets or classes.

#1155CC is the default color for Gmail links. You can overwrite this color using inline CSS. However, Gmail ignores #000, #000000, and “black” values. 

Here below we explain with some examples how to override these standards gmail css styles.

For example:

This will render as red:
<a href=“http://www.addemar.com” style=“color:#C00”>test</a> 

This will be rendered as the default (#1155CC) color:
<a href=“http://www.addemar.com” style=“color:#000000”>test</a> 

To fix this use a different hex value that is close to black:
<a href=“http://www.addemar.com” style=“color:#040400”>test</a> 

Underline
Links in Gmail are underlined by default. You can overwrite this style using inline CSS.

For example:
This will render with an underline:
<a href=“http://www.addemar.com”>test</a> 

This will render without an underline:
<a href=“http://www.addemar.com” style="text-decoration:none">test</a>