Add Mandelbrot tips to ? button content

Author: philthompson

index.html

@@ -592,7 +592,10 @@
     </div>
     <div id="help-menu">
         <span style="position: fixed; left: 1.2rem; top: 1.2rem;" id="help-menu-close">×</span>
-        <p style="clear: both; margin-left: -1.0rem; padding-top: 1.0rem">mouse</p>
+        <p style="clear: both; margin-left: -1.0rem; padding-top: 1.0rem">tips for the Mandelbrot set plot (<a target="_blank" href="https://philthompson.me/very-plotter-tips.html">more tips</a>)</p>
+        <p>screen black? increase iterations with M key or settings menu</p>
+        <p>too slow? add a few workers with U key or settings menu</p>
+        <p style="clear: both; margin-left: -1.0rem">mouse</p>
         <p>drag mouse to move &mdash; scroll mouse wheel to zoom</p>
         <p>hold alt (option on Mac) and drag mouse to zoom</p>
         <p>hold shift and click to re-center (good for slow-to-draw plots)</p>