Update css-forms-1/Overview.bs

Co-authored-by: Tim Nguyen <nt1m@users.noreply.github.com>

Author: lukewarlow

css-forms-1/Overview.bs

@@ -504,7 +504,7 @@ Markup Shorthands: css yes, markdown yes
   <div class="example" id="color-swatch-example">
     For example, the following example should make the input and its color swatch rounded:
 
-    <pre class="lang-css">input[type=color], ::color-swatch { border-radius: 9999px; }</pre>
+    <pre class="lang-css">input[type=color], ::color-swatch { border-radius: 100%; }</pre>
   </div>
 
 ## Compatibility With Vendor Pseudo-Element Extensions ## {#vendor-pseudo-element-compatibility}