Creating Thumbnail Picture grid in Ember using Picnicss

currently I'm in the state of confusion. I'm working of a project using one of its component in picnicss that card. so Im trying to build picture thumbnails like this :

X X X X X
X X X X X
X X X X X

where x is a picture probably with 200px * 200 px

the problem is when i tried to do like this

<div class="row">
{{#each model}}
<div class="third">
<article class="card">
<img {{bind-attr src="someimage"}}>
</article>
</div>
{{/each}}
</div>

it will not show all my images(let say i have 100 images), how to let {{#each}} know that every 7 data it will need to have new row??

thanks