try this method

<template id="product_configuration_inherit" inherit_id="website_sale.product">
            <xpath expr="//hr[@t-if='product.description_sale']" position="before">
                <div t-if="product.attribute_line_ids.ids">
                    <a  id="hidden_box_btn"  class="btn btn-primary btn-lg o_default_snippet_text">configure</a>
                </div>
                <div   id="hidden_box" class="modal fade">
                    <div class="modal-dialog modal-content" style="border:solid 5px red; min-height:200px;max-width:400px;">
                        <div class="modal-body" id="pop_html">
                            <a href="#" class="o_popup_btn_close o_not_editable o_default_snippet_text pull-right" data-dismiss="modal" style="font-size:30px">×</a>
                            <br/>
                            <h2 style="text-align:center; font-size 24px; font-weight:bold" class="o_default_snippet_text">Great, Let's Get Started</h2>
                           
                            <form action="/web/product/configure" method="GET">
                                <div align="center">
                                    <input type="hidden" name="product_id"  t-att-value="product.id"/>
                                   
                                        <t t-foreach="product.attribute_line_ids" t-as="atr_val">
                                            <table>
                                                <tr>
                                                    <td>
                                                        <t t-esc="atr_val.display_name"/>
                                                    </td>
                                                    <td>
                                                        <input type="text" t-att-name="atr_val.id" class="form-control" style="margin-top:15px"/>
                                                    </td>
                                                 </tr>
                                                
                                            </table>
                                        </t>
                                    <input type="date" name="date" class="form-control" style="margin-top:15px"/>
                                </div>
                                <div align="center" style="margin-top:15px">
                                    <input type="submit" value="Configure" class="btn btn-default btn-primary pull-center mb32"/>
                                </div>
                            </form>
                           
                           
                           
                        </div>
                    </div>
                       
               
                </div>   

        </xpath>   
        </template>

use java script

$("#hidden_box_btn").on('click', function () {
                    $('#hidden_box').modal('show');
                });