Drupal link inside bootstrap thumbnail I inserted this with a new created Text format

    &lt;div class="col-sm-6 col-md-4 "&gt;
   &lt;a href="#" target="_blank" class="thumbnail"&gt;
      &lt;img alt="test" src="#" /&gt;
     &lt;h3&gt;test&lt;/h3&gt;
     &lt;div class="mail"&gt;&lt;a href="mailto:test@test.ch"&gt;E-mail&lt;/a&gt;&lt;/div&gt;
   &lt;/a&gt;
&lt;/div&gt;


but drupal outputs this when i save the content

&lt;div class="col-sm-6 col-md-4 "&gt;
   &lt;a class="thumbnail" target="_blank" href="#"&gt;
      &lt;img src="#" alt="#"&gt;
     &lt;h3&gt;Test&lt;/h3&gt;
   &lt;/a&gt;
&lt;div class="mail"&gt;&lt;a class="thumbnail" target="_blank" href="#"&gt;&lt;/a&gt;&lt;a href="#"&gt;E-mail&lt;/a&gt;&lt;/div&gt;
&lt;/div&gt;


I want that the div mail is inside the anchor thumbnail but drupal strips out the anchor automaticly out of the anchour thumbnail. 

Can anybody tell me how i can fix that?
Nested &lt;a&gt; elements (anchor tags) are forbidden in HTML syntax.

Nested links are illegal by w3.org rules.