简单，首先复制默认login.html的form部分，再把登录js地址改成，例如下面

<form class="login-form" id="myform" action="" method="post">
    <h3 class="form-title font-green">会员登录</h3>

    <div class="form-group">
        <label class="control-label visible-ie8 visible-ie9">会员名称</label>
        <input class="form-control form-control-solid placeholder-no-fix" type="text" autocomplete="off" placeholder="Username" name="data[username]" />
    </div>
    <div class="form-group">
        <label class="control-label visible-ie8 visible-ie9">登录密码</label>
        <input class="form-control form-control-solid placeholder-no-fix" type="password" autocomplete="off" placeholder="Password" name="data[password]" />
    </div>
    <div class="form-group">
        <div class="col-sm-6" style="padding-left:0;padding-right:0">
            <input class="form-control form-control-solid placeholder-no-fix" type="text" autocomplete="off" placeholder="验证码" name="code" />
        </div>
        <div class="col-sm-6">
            <img align="absmiddle" style="cursor:pointer;" onclick="this.src='{dr_member_url('api/captcha', array('width' => 120, 'height' => 40))}&'+Math.random();" src="{dr_member_url('api/captcha', array('width' => 120, 'height' => 40))}" />
        </div>
    </div>
    <div class="form-actions">
        <button type="button" onclick="dr_submit()" class="btn green uppercase">登录</button>
    </div>
    <div class="login-options" style="margin-bottom: 10px">
        <ul class="social-icons">
            {list action=cache name=oauth}
            <li>
                <a class="social-icon-color facebook" style="border-radius:0!important;background-position:0 0!important;background: url({THEME_PATH}oauth/{$t.id}.png) no-repeat" href="javascript:;" onclick="window.location.href='{dr_member_url('api/oauth')}&id={$t.id}'">

                </a>
            </li>
            {/list}
        </ul>
    </div>
</form>

<script type="text/javascript">
    function dr_submit() {
        var post = $("#myform").serialize();
        $.ajax({type: "POST",dataType:"json", url: "{dr_member_url('login/index')}", data: post,
            success: function(data) {
                if (data.status) {
                    dr_tips('登录成功，即将为您跳转....', 3, 1);
                    setTimeout('window.location.href="'+data.backurl+'"', 2000);
                    var sync_url = data.syncurl;
                    // 发送同步登录信息
                    for(var i in sync_url){
                        $.ajax({
                            type: "GET",
                            async: false,
                            url:sync_url[i],
                            dataType: "jsonp",
                            success: function(json){ },
                            error: function(){ }
                        });
                    }
                } else {
                    dr_tips(data.code);
                }
            },
            error: function(HttpRequest, ajaxOptions, thrownError) {
                alert(HttpRequest.responseText);
            }
        });
    }
</script>

以上代码可以放到任意一个页面上