Added colouring

orbitals.html

@@ -87,6 +87,10 @@
         So this widget just plots the radius of the complex number. Think of complex numbers as points in 2D space. I plot the distance
         of that point from the origin.
     </p>
+    <p>
+        Since this function can also return negative values, it is common to plot the absolute value, and colour regions according to their sign.
+        Here, green represents non-negative values and red represents negative values.
+    </p>
     <br>
     <br>
     <table>