Add scrolling content style

src/definitions/modules/modal.less

@@ -377,6 +377,13 @@
   }
 }
 
+/* Scrolling Content */
+
+.ui.modal .scrolling.content {
+  max-height: @scrollingContentMaxHeight;
+  overflow: auto;
+}
+
 
 /*--------------
    Full Screen

src/themes/default/modules/modal.variables

@@ -115,6 +115,9 @@
 @scrollingMargin: 3.5rem;
 @mobileScrollingMargin: 1rem;
 
+/* Scrolling Content */
+@scrollingContentMaxHeight: calc(80vh - 10em);
+
 /*-------------------
       Variations
 --------------------*/
@@ -176,4 +179,4 @@
 @largeTabletMargin: 0em 0em 0em -(@largeTabletWidth / 2);
 @largeComputerMargin: 0em 0em 0em -(@largeComputerWidth / 2);
 @largeLargeMonitorMargin: 0em 0em 0em -(@largeLargeMonitorWidth / 2);
-@largeWidescreenMonitorMargin: 0em 0em 0em -(@largeWidescreenMonitorWidth / 2);
+@largeWidescreenMonitorMargin: 0em 0em 0em -(@largeWidescreenMonitorWidth / 2);