Css 材质UI样式如何从下图中的模式背景中删除线条

我尝试将边框设置为“无”，并将长方体阴影设置为“无”，但没有任何效果。这些线仅在单击模态体时显示。我省略了模态样式代码，因为它只包含flex样式等等。 以下代码是模式的实现：

`<Modal aria-labelledby="transition-modal-title" aria-describedby="transition-modal-description" 
            className={classes.modal} open={state.open} onClose={handleClose} closeAfterTransition BackdropComponent={Backdrop}
            BackdropProps={{ 
                timeout: 500, classes: { root: classes.backDrop }
            }}
        >
            <Fade in={state.open}>
                <Column gap={2} style={{width:'50%',height:'70%'}}>
                    <Row
                        style={{width: '100%',position:'relative',left:'5%',marginTop:'2%', boxShadow:'none',border:'none' }} 
                        className={classes.modal}
                    >
                        <Item bgcolor="background.paper" position={'middle'} width={345.6} style={{borderRadius:'4px'}}>
                            {/***code cut out**/}
                            <br/>
                            <Button
                                style={{
                                    width: '60%', backgroundColor: 'white', marginLeft:'20%',
                                    color: "black", textTransform: 'none', fontSize: '10px', height:'12px'
                                }} variant="text"
                                onClick={handleClose}
                            ><b>Return to Nike store</b>
                            </Button>
                        </Item>
                        <IconButton onClick={handleClose} style={{
                            position: 'relative', top: '-60%', left: '7.7%', transform: 'translate(-50%, -50%)',
                        }}>
                            <ClearOutlinedIcon style={{
                                color:'#000',border:'1px solid #fff',borderRadius:'100%',background:'#fff',
                                width: '35px', height:'35px'
                            }} />
                        </IconButton>
                    </Row>
                    <Row
                        style={{width: '100%'}} 
                        className={classes.modal}
                    >
                        <Item position={'middle'} width={345.8}>                            
                            <Typography style={{color: "#fff", display: 'flex',
                                fontSize: '10px', justifyContent: 'center', maxWidth:'60%', marginLeft:'15%'
                            }}>
                                <Lock style={{ fontSize: '14px', justifyContent: 'center', fontFamily: 'Comfortaa'}} />
                                &nbsp; payments by &nbsp; <b>SlashIt</b>
                            </Typography>
                        </Item>
                    </Row>
                    <Row style={{width: '100%'}} className={classes.modal} >
                        <Item position={'middle'} width={345.8}>                            
                            <Typography style={{color: "#fff", display: 'flex',
                                fontSize: '10px', justifyContent: 'center', maxWidth:'60%', marginLeft:'17%',
                                marginTop:'-2%'
                            }}>
                                Terms &nbsp; &nbsp; &nbsp; Privacy
                            </Typography>
                        </Item>
                    </Row>
                </Column>
            </Fade>
        </Modal>`

`
{/***代码剪切**/}


返回Nike商店
分期付款
隐私条款
`

请添加更多关于您是如何实现它的详细信息，或添加一个链接（例如codesandbox.io）来演示该问题。