fix: mailto-text-replace and c-button incompatible (#580)

- Added `:not(…)` to avoid applying to a Core-Styles button.
- Use nested CSS syntax to minimize footprint across files.
- Linked to example usage that has the problem.

Author: wesleyboar

dist/core-styles.base.css

@@ -1,6 +1,7 @@
 /* Allow supporting `u-mailto-text-replace` on all hyperlinks */
 /* FAQ: Only included by a project as client wants it */
 /* SEE: https://ecepalliance.org/about/leadership/ */
+/* SEE: https://ecepalliance.org/alliance-members/ */
 
 @import url("../tools/x-mailto-text-replace.css");
 

dist/core-styles.cms.css

@@ -6,18 +6,23 @@ Replace mailto link rendered text with virtual text from data-attributes
 Styleguide Tools.Mixins.MailtoTextReplace
 */
 
+@import url("../components/c-button.selectors.css");
+
 /* To replace actual link text with generated link text */
 %x-mailto-text-replace {
-    /* FAQ: Using `display: none` would hide pseudo element text */
-    visibility: hidden; /* to hide actual link text */
-    font-size: 0; /* to remove space of hidden text */
-    /* CAVEAT: The `font-size: 0` causes underline to be too high */
-    /* HACK: So push underline down */
-    text-underline-offset: 0.3rem;
-}
-%x-mailto-text-replace::before {
-    display: inline;
-    content: attr(data-user) "@" attr(data-domain);
-    font-size: initial; /* to restore font size */
-    visibility: visible; /* to restore visibility */
+    &:not(:--c-button) {
+        /* FAQ: Using `display: none` would hide pseudo element text */
+        visibility: hidden; /* to hide actual link text */
+        font-size: 0; /* to remove space of hidden text */
+        /* CAVEAT: The `font-size: 0` causes underline to be too high */
+        /* HACK: So push underline down */
+        text-underline-offset: 0.3rem;
+
+        &::before {
+            display: inline;
+            content: attr(data-user) "@" attr(data-domain);
+            font-size: initial; /* to restore font size */
+            visibility: visible; /* to restore visibility */
+        }
+    }
 }