title: HTML CSS: change color of label, when option is selected
body: <p>I want to style a label of a select-tag in html. When the user didn't pick any 
  option, the color of the label should be white. If the user picked an option, the label should switch to white. </p>
  
  <p>html code: </p>
  
  <pre><code>    &lt;label class="titel" for="titel"&gt;Titel:&lt;/label&gt;
        &lt;select class="titel" name="titel"&gt;
          &lt;option value=""&gt;&lt;/option&gt;
          &lt;option value="Proffessor"&gt;Prof.&lt;/option&gt;
          &lt;option value="Doctor"&gt;Dr.&lt;/option&gt;
        &lt;/select&gt;
  </code></pre>
  
  <p>css code: </p>
  
  <pre><code>label.titel{color: white;}
  </code></pre>
  
  <p>What i tried, but didn't worked: </p>
  
  <pre><code>select.titel:checked + label.titel{color: black;}
  </code></pre>
  
  <p>I searched and i found out, for this kind of tasks the :checked pseudoclass is helpful. I can change the label color of radio buttons or checkboxes, when checked but not the label of a select-tag when option is checked. </p>
  
  <p>Thanks for your help in advance! </p>
  
  <p><strong>Edit:</strong> To make it more clear, as it mentioned @Rembrand Reyes in a comment "The drop down when blank will have Title displayed white, but when the user picks title, it will color the label black?"</p>