counting with variable to do a trick in my gallery (newb)

[Vandenberg]

Hello, let me introduce. 24ish designer from the Netherlands, getting more and more into development. I love symphony, my newest subject.

please some advice on this matter:

I have a gallery fed by xml. It shows 12 images. When a gallery has, for example, only 3 entries, I need to fill the rest of the vacant spots up with gray crosses. I tried counting the modulus, and it prints out right.

Sadly now I don't know how to make the equation in xsl, having the right number, but lacking a decent for loop, and i grow tired of tinkering now. 3 days ago i never even heard of xslt so

Here's the code

<p>
     <xsl:variable name="fillernokiller" select="12 - count(/data/fotos/entry)" />
     <xsl:value-of select="$fillernokiller" />
</p>
                                        
<xsl:if test="fillernokiller < 12">
     <li class="image">
          <img src="{$assets}/images/empty.jpg" height="90" width="90" />
     </li>
</xsl:if>

Here's the code in context

<div class="left">
    <ul id="thumbs" class="images" >
        
    <xsl:for-each select="/data/fotos/entry">
        <li class="image">

                <a rel="lightbox-mygallery" href="/workspace{afbeelding/@path}/{afbeelding/filename}" title="{omschrijving}">                                       <div class="container" >
                        <img src="/image/2/90/90/5/0{afbeelding/@path}/{afbeelding/filename}" style="z-index: 1;"  alt="{omschrijving}" height="90" width="90" class="thumb" />
                    </div>                                                        
                </a>
        </li>
    </xsl:for-each>
    
    <p>
        <xsl:variable name="fillernokiller" select="12 - count(/data/fotos/entry)" />
        <xsl:value-of select="$fillernokiller" />
    </p>
    
    <xsl:if test="fillernokiller> 0">
        <li class="image">
            <img src="{$assets}/images/empty.jpg" height="90" width="90" />
        </li>
    </xsl:if>
                                                  
    </ul>
</div>
             
<div id="categories">
    <ul>
        <xsl:for-each select="/data/galerien/entry">
            <li>
                <a href="/home/{titel/@handle}" id="{titel/@handle}">
                     <xsl:value-of select="titel" />
                </a>
            </li>
        </xsl:for-each>
    </ul>
</div>

[Vandenberg]

Is my post unclear?