The source code

    /**
     * @ignore
     * effect for dialog
     * @author yiminghe@gmail.com
     */
    KISSY.add('overlay/extension/dialog-effect', function (S) {

        function DialogEffect() {

        }

        DialogEffect.prototype = {

            // also simplify body
            __afterCreateEffectGhost: function (ghost) {
                var self = this,
                    body,
                    elBody = self.get("body");

                ghost.all('.' + self.get('prefixCls') + 'stdmod-body')
                    .css({
                        height: elBody.height(),
                        width: elBody.width()
                    })
                    .html('');

                return ghost;
            }

        };

        return DialogEffect;

    });