title: PHP and HTML 5 validation message
body: <p>I would like to know how do I edit in HTML5 validation message if there is error in form.</p>
  
  <pre><code>&lt;form method="post" id="login" action="&lt;?php echo $_SERVER['PHP_SELF']?&gt;"&gt;
      &lt;div class="form_settings"&gt;
          &lt;label for="textfield"&gt;Meno:&lt;/label&gt;
          &lt;input class="zaoblene" type="text" name="meno" value="Meno....." onclick="javascript: document.forms['login'].meno.value=''" required&gt;
          &lt;br&gt;&lt;br&gt;
          &lt;label for="textfield"&gt;Heslo:&lt;/label&gt;
          &lt;input class="zaoblene" type="password" name="heslo" value="heslo....." onclick="javascript: document.forms['login'].heslo.value=''" required&gt;
          &lt;br&gt;&lt;br&gt;
          &lt;input class="prihlasit" type="submit" name="prihlasit" value="prihlásit" &gt;
       &lt;/div&gt;
   &lt;/form&gt;
  </code></pre>