Question

Is this HTML structure valid?

<ul class="blog-category">
  <div class="three column">
    <li>Item 1</li> 
    <li>Item 2</li> 
    <li>Item 3</li> 
  </div>
  <div class="three column">
    <li>Item 4</li> 
    <li>Item 5</li> 
    <li>Item 6</li> 
  </div>
  <div class="three column">
    <li>Item 7</li> 
    <li>Item 8</li> 
    <li>Item 9</li> 
  </div>
</ul>

I am inserting li’s inside div which is within ul. What do you think? Is this stucture semantically valid and will that be recognized as a single list?

Answer 1

No, div is not allowed as a direct child of ul. Whenever you’re in doubt, validate your page with W3C or check the corresponding article on W3C:

4.5.6 The ul element

Categories
Flow content.

Contexts in which this element can be used:
Where flow content is expected.

Content model:
Zero or more li elements.

Content attributes:
Global attributes

DOM interface:
interface HTMLUListElement : HTMLElement {};

Instead you could use

<ul class="blog-category">
    <li class="three column">
        <ul>
            <li>Item 1</li>
            <li>Item 2</li>
            <li>Item 3</li>
        </ul>
    </li>
    <li class="three column">
        <ul>
            <li>Item 4</li>
            ...
        </ul>
    </li>
</ul>