Text-decoration: none not working

You have a block element (div) inside an inline element (a). This works in HTML 5, but not HTML 4. Thus also only browsers that actually support HTML 5.

When browsers encounter invalid markup, they will try to fix it, but different browsers will do that in different ways, so the result varies. Some browsers will move the block element outside the inline element, some will ignore it.

Add this statement on your header tag:

<style>
a:link{
  text-decoration: none!important;
  cursor: pointer;
}
</style>

a:link{
  text-decoration: none!important;
}

=> Working with me :) , good luck

Use CSS Pseudo-classes and give your tag a class, for example:

<a class="noDecoration" href="#">

and add this to your stylesheet:

.noDecoration, a:link, a:visited {
    text-decoration: none;
}