Improve docs

web/index.html

@@ -46,11 +46,14 @@
         <canvas id="canvas" width="256" height="240">
         </canvas>
         <p>
-            Drag and drop a ROM to the window to play it. Try the <a
+            This is a <a
+                href="https://www.nintendo.com/en-gb/Hardware/Nintendo-History/Nintendo-Entertainment-System/Nintendo-Entertainment-System-627024.html">NES</a>
+            emulator. Drag-and-drop a .nes or .zip file to the window to play it, e.g. the <a
                 href="https://eldenpixels.itch.io/alwas-awakening-the-8-bit-edition#:~:text=944%20kB-,Download%20demo,-Download">Alwa's
-                Awakening demo</a>! No need to unzip.
+                Awakening demo</a>!
         </p>
         <p>
+            Controls:&nbsp;
             <span class=key>Z</span> = <span class=button>A</span>,&nbsp;
             <span class=key>X</span> = <span class=button>B</span>,&nbsp;
             <span class=key>Arrows</span> = <span class=button>D-Pad</span>,&nbsp;