Dropdown options from Search and Filter WP Plugin vanish upo

Hello all,

I recently upgraded to MDB jQuery Pro. All is amazing, except for a style rule (within mdb.css/mdb.min.css) which makes the dropdown selectors disappear from a Wordpress Plugin called Search and Filter.

What I know is:

-The plugin worked flawlessly while using the free version of MDB.

-The problem is coming from mdb.css/mdb.min.css, as disabling these stylesheets results in a functioning plugin, albeit a dull looking site.

I was wondering if there are <form>/<input>/<select>/<option> rules I can delete from MDB to leave the dropdown visible and working, to have a functioning filter in my website.

Plugin Shortcode:

Start your code here <?php echo do_shortcode( '[searchandfilter fields="category,post_tag,county,city" headings="Listing Type,Property Type,County,City"]' ); ?>

Plugin HTML on page source:

Start your code here

				<form action="" method="post" class="searchandfilter">
					<div>
						<ul><li><h4>Listing Type</h4><select  name='ofcategory' id='ofcategory' class='postform' >
	<option value='0' selected='selected'>All</option>
	<option class="level-0" value="4">For Lease</option>
	<option class="level-0" value="5">For Sale</option>
</select>
<input type="hidden" name="ofcategory_operator" value="and" /></li><li><h4>Property Type</h4><select  name='ofpost_tag' id='ofpost_tag' class='postform' >
	<option value='0' selected='selected'>All</option>
	<option class="level-0" value="17">Office</option>
	<option class="level-0" value="18">Retail</option>
</select>
<input type="hidden" name="ofpost_tag_operator" value="and" /></li><li><h4>County</h4><select  name='ofcounty' id='ofcounty' class='postform' >
	<option value='0' selected='selected'>All Counties</option>
	<option class="level-0" value="56">McHenry County</option>
</select>
<input type="hidden" name="ofcounty_operator" value="and" /></li><li><h4>City</h4><select  name='ofcity' id='ofcity' class='postform' >
	<option value='0' selected='selected'>All Cities</option>
	<option class="level-0" value="59">Crystal Lake</option>
</select>
<input type="hidden" name="ofcity_operator" value="and" /></li><li><input type="hidden" name="ofsubmitted" value="1">
							<input type="submit" value="Submit">
						</li></ul></div>
				</form></div>