用PHP填充3个项目后循环DIV块

I have the following raw HTML code:

<section class="cols services-modern">
    <div class="container">
        <div class="row-fluid">
            <div class="span4">
                <i class="content"></i>
                <h3>Title</h3>
                <p>Blah.....</p>
            </div>
            <div class="span4">
                <i class="content"></i>
                <h3>Title</h3>
                <p>Blah.....</p>
            </div>
            <div class="span4">
                <i class="content"></i>
                <h3>Title</h3>
                <p>Blah.....</p>
            </div>
        </div>
    </div>
</section>

Which i would like to loop after the div has been filled with 3 contents. So far i have done the following with no luck..

<?php for($i = 0; $i < sizeof($content); $i++) : ?>
<section class="cols services-modern">
    <div class="container">
        <div class="row-fluid">
<?php if($i % 3 == 0): ?>
    <div class="span4">
        <i class="content"></i>
        <h3>Title</h3>
        <?= htmlspecialchars_decode($blah); ?>
    </div>
<?php else: ?>
    <div class="span4">
        <i class="content"></i>
        <h3>Title</h3>
        <?= htmlspecialchars_decode($blah); ?>
    </div>
<?php endif; ?>
</div>
</div>
</section>
<?php endfor; ?>

Could anyone help me to spot my mistake, thanks.

This is what u expecting?

<section class="cols services-modern">
  <div class="container">
    <div class="row-fluid">
    <?php for($i = 0; $i < sizeof($content); $i++) : if($i % 3 == 0): ?>
      <div class="span4"> <i class="content"></i>
        <h3>Title</h3>
        <?= htmlspecialchars_decode($blah); ?>
      </div>
      <?php else: ?>
      <div class="span4"> <i class="content"></i>
        <h3>Title</h3>
        <?= htmlspecialchars_decode($blah); ?>
      </div>
      <?php endif; endfor; ?>
    </div>
  </div>
</section>

try this one..

<?php for($i = 0; $i < sizeof($content); $i++) : if($i % 3 == 0): ?>
<section class="cols services-modern">
  <div class="container">
    <div class="row-fluid">

      <div class="span4"> <i class="content"></i>
        <h3>Title</h3>
        <?= htmlspecialchars_decode($blah); ?>
      </div>
      <?php else: ?>
      <div class="span4"> <i class="content"></i>
        <h3>Title</h3>
        <?= htmlspecialchars_decode($blah); ?>
      </div>

    </div>
  </div>
</section>
<?php endif; endfor; ?>