clarify some docs for form validation including quick mention for customizing or...

diff --git a/docs/components/forms.md b/docs/components/forms.md
index e6439ae25a4f46f8cb4ff72358daf8733da21f3d..fed3ba399c496f6decd51a7cde8882b79d2d52dd 100644 (file)
--- a/docs/components/forms.md
+++ b/docs/components/forms.md
@@ -634,7 +634,12 @@ Block help text—for below inputs or for longer lines of help text—can be eas
 
 ## Validation
 
-Bootstrap includes validation styles for danger, warning, and success states on form controls. To use, add `.has-warning`, `.has-danger`, or `.has-success` to the parent element. Any `.form-control-label`, `.form-control`, and `.text-help` within that element will receive the validation styles.
+Bootstrap includes validation styles for danger, warning, and success states on form controls.
+
+- To use, add `.has-warning`, `.has-danger`, or `.has-success` to the parent element. Any `.form-control-label`, `.form-control`, and `.text-help` within that element will receive the validation styles.
+- Validation icons are `url()`s configured via Sass variables that are applied to `background-image` declarations for each state.
+- You may use your own base64 PNGs or SVGs by updating the Sass variables and recompiling.
+- Icons can also be disabled entirely by changing the variables to `non` or commenting out the source Sass.
 
 {% comment %}
 {% callout warning %}