Hey Daniel,
Thanks for this report. I agree our color choices aren't the best for visually impaired users. Unfortunately, I don't think we can change the colors in Atlas to be WCAG 2.0 compliant at this point in the project. There is always the option to fall back to Bootstrap 3's colors with Lexicon Base (Styled theme in 7.0). It's better, but probably won't meet your requirements 100%.
The best option at this point is to customize the colors to meet your requirements. We have mapped the colors for each component to a Sass variable that can be overridden through the file
_aui_variables.scss in 7.0. You just need to add that file to your theme in the same directory as
_custom.scss and make sure to add (at the beginning of the file):
$FontAwesomePath: "aui/lexicon/fonts/alloy-font-awesome/font";
$font-awesome-path: "aui/lexicon/fonts/alloy-font-awesome/font";
$icon-font-path: "aui/lexicon/fonts/";
You will have to do all the color calculations and set them yourself. Something that we can add to Lexicon 1.x is a Sass function that will color the text for you based on the background-color of the component or vise versa. Bootstrap 4 has added this and we can easily copy it over. See
https://github.com/twbs/bootstrap/blob/v4-dev/scss/_functions.scss#L52.
How it would work is:
$alert-success-bg: #DDF3D5;
$alert-success-text: color-yiq($alert-success-bg);
.alert-success would then have either a dark (#222) or a light (#FFF) text color. We might be able to add an additional block to return some color based on a formula. You will still need to set the variables, but it removes one variable you need calculate colors for. The color-yiq function can be added to your custom theme as well, just add the function to
_aui_variables.scss and make sure the variables are declared after the function.
One thing thats been on the back burner is something to help ease the pain of learning/using the Sass variable api. It's pretty massive. I might be able to put together some kind of template _aui_variables.scss file that lists all the variables that you can customize and in the proper order later this week. I will get back to you.
