8-11 templates/op_search_form.tpl

<form action="search.php" method="get">
    <div class="input-group">
        <input type="text" name="keyword" class="form-control" placeholder="&#xf002;以空白隔開關鍵字" aria-label="Search for..." style="font-family: 微軟正黑體, FontAwesome">
        <span class="input-group-btn">
            <button class="btn btn-secondary" type="submit"><i class="fa fa-search" aria-hidden="true"></i></button>
        </span>
    </div>
</form>