If you have Quickstart of JD Boston then open the chronoforms Component and open form1 and click on code tab and see the code. We did this use bootstrap class.code are below.
<div class="form-group gcore-form-row" id="form-row-custom">
<div class="gcore-input center m-title-upper" id="fin-custom">
<h3 class="module-title ">
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