找到电脑注册模板 template\网站当前电脑模板目录\member\register.htm
通过id="{$this->setting['reginput']['username']}"查找，把class="px"修改为class="px it618_username"
通过id="{$this->setting['reginput']['password']}"查找，把class="px"修改为class="px it618_password1"
通过id="{$this->setting['reginput']['password2']}"查找，把class="px"修改为class="px it618_password2"
找到手机注册模板 template\网站当前手机模板目录\touch\member\register.htm
通过name="{$this->setting['reginput']['username']}"查找，把class="px p_fre"修改为class="px p_fre it618_username"
通过name="{$this->setting['reginput']['password']}"查找，把class="px p_fre"修改为class="px p_fre it618_password1"
通过name="{$this->setting['reginput']['password2']}"查找，把class="px p_fre"修改为class="px p_fre it618_password2"
修改好了，最好在论坛后台更新一下缓存。