그누보드5 썸네일 도와주세요ㅠㅠ

<div class="container">        <div class="row">            <div class="col-lg-12 text-center">                <h2>포트폴리오</h2>                <hr class="star-primary">            </div>        </div>        <div class="row">            <?php            $bo_table = '3_1';            $sql = "SELECT * FROM g5_write_{$bo_table}                    WHERE wr_is_comment = '0'                    ORDER BY wr_num                    LIMIT 0, 100";            $rst = sql_query($sql);            $board = array('bo_table' => $bo_table);            $i = 0;            while($row = sql_fetch_array($rst)) {                $row = get_list($row, $board, G5_URL);                $thumbnail = get_list_thumbnail($bo_table, $row['wr_id'], 1024, 650);            ?>            <div class="col-sm-4 portfolio-item">                <a href="#portfolioModal<?php echo $i?>" class="portfolio-link" data-toggle="modal">                    <div class="caption">                        <div class="caption-content">                            <i class="fa fa-search-plus fa-3x"></i>                        </div>                    </div>                    <img src="<?php echo $thumbnail['src']?>" class="img-responsive img-centered" alt="<?php echo $thumbnail['alt']?>">                </a>            </div>            <div class="portfolio-modal modal fade" id="portfolioModal<?php echo $i?>" tabindex="-1" role="dialog" aria-hidden="true" style="z-index:9999">                <div class="modal-content">                    <div class="close-modal" data-dismiss="modal">                        <div class="lr">                            <div class="rl">                            </div>                        </div>                    </div>                    <div class="container">                        <div class="row">                            <div class="col-lg-8 col-lg-offset-2">                                <div class="modal-body">                                    <h2><?php echo $row['subject']?></h2>                                    <hr class="star-primary">                                    <img src="<?php echo $thumbnail['src']?>" class="img-responsive img-centered" alt="<?php echo $thumbnail['alt']?>">                                    <p><?php echo conv_content($row['wr_content'], 2)?></p>                                    <ul class="list-inline item-details">                                        <li>Client:                                            <strong><?php echo $row['name']?>                                            </strong>                                        </li>                                        <li>Date:                                            <strong><?php echo date('F d, Y', strtotime($row['wr_datetime']))?>                                            </strong>                                        </li>                                        <li>Category:                                            <strong><?php echo $row['ca_name']?>                                            </strong>                                        </li>                                    </ul>                                    <button type="button" class="btn btn-default" data-dismiss="modal"><i class="fa fa-times"></i> Close</button>                                </div>                            </div>                        </div>                    </div>                </div>            </div>            <?php $i += 1;            } ?>        </div>    </div>