如何改變antd里面的默認樣式

 <div className={styles.ca}>
                <ActivityIndicator size='large' animating={this.props.loading} toast text="頁面加載中..." />
            </div>

css代碼如下

.ca{

}
.ca :global .am-activity-indicator.am-activity-indicator-toast{
background-color: #ffffff;
z-index: 99999;
}