Merge pull request #11462 from ncoden/fix/reveal-mobile-full-height-10879

fix: avoid viewport height for fullscreen Reveal as it may be incorrect #10879

Author: ncoden

scss/components/_reveal.scss

@@ -113,13 +113,14 @@ $reveal-overlay-background: rgba($black, 0.45) !default;
 /// Creates a full-screen modal, which stretches the full width and height of the window.
 @mixin reveal-modal-fullscreen {
   top: 0;
+  right: 0;
+  bottom: 0;
   left: 0;
 
   width: 100%;
   max-width: none;
   height: 100%;
-  height: 100vh; // sass-lint:disable-line no-duplicate-properties
-  min-height: 100vh;
+  min-height: 100%;
   margin-left: 0;
 
   border: 0;