form#reset_password ul {

    list-style: none;

    margin: 0 0 20px 200px;

    padding:;

}

form#reset_password ul li:first-child {

    display: inline;

    line-height: 34px;

    padding-left: 10px;

}

form#reset_password ul li:nth-child(2) {

    float: left;

    line-height: 34px;

}

form#reset_password ul li:last-child {

    float: left;

}

<form id="reset_password">

    <input type="hidden" name="rt" value="<?= $msg['reset_time'] ?>">

    <input type="hidden" name="uname" id="uname" value="<?=$msg['username'];?>">

    <ul>

        <li></li>

        <li>&emsp;用户名</li>

        <li><input class="form-control" type="text" value="<?=$msg['username'];?>"

            placeholder="" autocomplete="off" disabled /></li>

    </ul>

    <ul>

        <li></li>

        <li>&emsp;新密码</li>

        <li><input class="form-control" type="password" name="newpwd" id="newpwd" value=""

            autocomplete="off" placeholder="请输入您的新密码" /></li>

    </ul>

    <ul>

        <li></li>

        <li>确认密码</li>

        <li><input class="form-control" type="password" name="repeat_pwd" id="repeat_pwd" value=""

            autocomplete="off" placeholder="请再次输入您的新密码以进行确认" /></li>

    </ul>

    <p><button id="save_new_pwd" class="btn btn-success">确认修改</button></p>

</form>