モデル内の3つのアイテムごとに連続してラップする必要があります。
現在持っている:
<% for(var i = 0; i <= Model.Count()/3; i++ ) { %>
<div class="row row-md">
<div class="content-normal">
<% foreach (var challenge in Model) { %>
<div class="grid grid-col-3up">
<div class="mod mod-games">
<div class="mod-hd">
<h5 class="heading heading-mod heading-mod-5up heading-muted">Week 1</h5>
</div>
<div class="mod-box-banner">
<div class="mod-banner-box">
<% if (challenge.Completed) { %>
<img src="assets/images/completed-banner.png" alt="" class="mod-completed-banner"/>
<% } %>
</div>
<div class="mod-box mod-relative ">
<% if (challenge.Completed) { %>
<img src="assets/images/medal-game.png" alt="" class="mod-medal-game" />
<span class="mod-game-entries"><%= challenge.Entries%> Entries Earned</span>
<img src="assets/images/games-burst.png" alt="" class="mod-box-img">
<% } else { %>
<img src="<%= challenge.Image %>" alt="" class="mod-box-img" />
<% } %>
</div>
</div>
<div class="mod-hd">
<h4 class="heading heading-mod heading-mod-3up heading-muted"><%= challenge.ChallengeTitle%></h4>
</div>
<div class="mod-hr">
<hr>
</div>
<div class="mod-bd">
<p><%= challenge.ShortDescription%></p>
</div>
<div class="mod-btn no-pad">
<a href="<%= challenge.ChallengeUrl %>"class="btn">
Play
<% if (challenge.Completed) { %>
Again
<% } %>
</a>
</div>
<div class="mod-btn">
<a href="#" class="btn">Share</a>
</div>
</div>
</div>
<% } %>
</div>
</div>
<% } %>
最初のforeachはOverFlowExceptionをスローします。