<form class="search-form" method="GET" action="https://www.baidu.com/s?">
    <input name="wd" type="text" class="search-form-input" style="height: 42px; width: 75%;" placeholder="<%= __('search') %>..." />
    <button type="submit" class="search-form-submit"><%= __('search') %></button>
</form>
<script>
(function ($) {
    $('.search-form').on('submit', function (e) {
        var keyword = $('.search-form-input[name="wd"]').val();
        window.location = 'https://www.baidu.com/s?wd=site:<%= config.url.replace(/http(s)*:\/\//, "") %> ' + keyword;
        return false;
    });
})(jQuery);
</script>