If FragmentText is empty add style to containg div

[graphicz]

My fragment is contained in a div:

<div class="col-md-12 product-details">

<div class="thumbnail">
<actinic:block if="%3cactinic%3avariable%20name%3d%22FragmentImageFileName%22%20%2f%3e%20%21%3d%20%22%22">
<actinic:variable formatting="div,style|set-right" name="FragmentImage" />
</actinic:block>
<actinic:block if="%3cactinic%3avariable%20name%3d%22FragmentTitle%22%20%2f%3e%20%21%3d%20%22%22">
<actinic:variable formatting="h2" name="FragmentTitle" />
</actinic:block>
<actinic:variable formatting="div,style|fragment-text" name="FragmentText" />
<div class="clearfloat"></div>
</div>
</div>

I want to hide the fragment if the Fragment Text is empty, but doing this causes errors:

<div class="col-md-12 product-details"<actinic:block if="%3cactinic%3avariable%20name%3d%22FragmentText%22%20%2f%3e%20%3d%3d%20%22%22"> style="display:none;"</actinic:block>>

Is there a work around anyone can think of?

Thank you

[NormanRouxel]

This will generate the <div ...> tag:

<div class="col-md-12 product-details"
<actinic:block php="true">
$fragtext = <<<ENDOFCODE
<actinic:variable name="FragmentText" />
ENDOFCODE;
if ( strlen($fragtext) == 0 ) echo ' style="display:none;"';
</actinic:block>
>

Note that this code must not be indented.

[graphicz]

Thank you so much Norman. Best wishes.