How to disable (or change color) of 2nd drop down option depenging on 1st selection?
<p>My problem is "how to change an options color (or disable) within a second drop down list depending on a first selection?" with javascript / jquery.</p>

<p>For example: If selected "13 Stairs" in my first drop down list 14 and 15 Stairs should have color "red" <strong><em>(or disabled)</em></strong> in the second drop down.</p>

<p>Something like "if option==13 Stairs* -> 14* / 15* == disabled" or
"if selected value "a" -> value "m-r" = red."</p>

<p>Perhaps its very easy, but I'm a completly nood in Javascript. :(
Hopefully someone can hep me.</p>

<pre><code>&lt;form id="test" name="test" method="post" action=""&gt;
    &lt;label for="demo"&gt;&lt;/label&gt;
    &lt;select name="first-election" id="first-election"&gt;
      &lt;option value="a"&gt;13 Stairs - 001&lt;/option&gt;
      &lt;option value="b"&gt;13 Stairs - 002&lt;/option&gt;
      &lt;option value="c"&gt;13 Stairs - 003&lt;/option&gt;
      &lt;option value="d"&gt;14 Stairs - 001&lt;/option&gt;
      &lt;option value="e"&gt;14 Stairs - 002&lt;/option&gt;
      &lt;option value="f"&gt;14 Stairs - 003&lt;/option&gt;
      &lt;option value="g"&gt;15 Stairs - 001&lt;/option&gt;
      &lt;option value="h"&gt;15 Stairs - 002&lt;/option&gt;
      &lt;option value="i"&gt;15 Stairs - 003&lt;/option&gt;
    &lt;/select&gt;
&lt;br /&gt;&lt;br /&gt;
    &lt;select name="color" id="color"&gt;
      &lt;option value="j"&gt;13 Stairs - green&lt;/option&gt;
      &lt;option value="k"&gt;13 Stairs - yellow&lt;/option&gt;
      &lt;option value="l"&gt;13 Stairs - black&lt;/option&gt;
      &lt;option value="m"&gt;14 Stairs - green&lt;/option&gt;
      &lt;option value="n"&gt;14 Stairs - yellow&lt;/option&gt;
      &lt;option value="o"&gt;14 Stairs - black&lt;/option&gt;
      &lt;option value="p"&gt;15 Stairs - green&lt;/option&gt;
      &lt;option value="q"&gt;15 Stairs - yellow&lt;/option&gt;
      &lt;option value="r"&gt;15 Stairs - black&lt;/option&gt;
    &lt;/select&gt;
&lt;/form&gt;
</code></pre>
