accessibility – Is there a standard to indicate a high contrast style?

I am working on a web application and have developed a normal style sheet and a high contrast secondary style sheet. I am confused when it comes to allowing a user to change their style.

Is there a standard icon / text to use?

Until now, I have links as follows (the high contrast is visible only in normal view and the normal view is visible only in high contrast ).

switch to high contrast
switch to normal view