Help with organizing fieldset

I'm making a custom character sheet, but I have run into the problem that with different items and such Its hard to organize the sheet. The code below is what I am using for my inventory and I was wondering if you all have any advice for ways I can organize, be it closable folders, or more

</fieldset>

    <hr/>

    <label class="txt" style="font-size:1.8em;text-decoration:underline;">Inventory</label>

<fieldset class="repeating\_items">

<select name="attr\_rank" class="rank">

<option value="E">E</option>

<option value="D">D</option>

<option value="C">C</option>

<option value="B">B</option>

<option value="A">A</option>

<option value="S">S</option>

<option value="EX">EX</option>

</select>

<input type="text" name="attr\_itemsname" /><span>count:</span><input type="number" name="attr\_itemscount" />

        <button type='roll' name='item\_roll' value='&{template:default} {{name=@{character\_name}}} {{item=@{itemsname} (@{rank})}} {{=@{items}}}'></button>

        <textarea name="attr\_items" rows="1" cols="50"></textarea>

</fieldset>