使用 bootstrap-datepicker.css
https://github.com/uxsolutions/bootstrap-datepicker
<link th:rel="stylesheet" th:href="@{assets/bootstrap-datepicker/css/bootstrap-datepicker.css}"/>
<link th:rel="stylesheet" th:href="@{assets/bootstrap-datepicker/css/bootstrap-datepicker.standalone.css}"/>
<script th:src="@{assets/bootstrap-datepicker/js/bootstrap-datepicker.js}"></script><label for="birthdate">Date of birth</label>
<div class="input-group date">
<input type="text" class="form-control" id="birthdate" autocomplete="off" th:field="*{birtdate}"/>
<div class="input-group-append">
<span class="input-group-text"><i class="far fa-calendar-alt"></i></span>
</div>
</div>