背景属性的问题有哪些？

@CustomDialog  
struct LiveCustomDialog {  
  controller: CustomDialogController  
  title: string | Resource = "提示"  
  content: string | Resource = ""  
  leftBtText: string | Resource = "取消"  
  rightBtText: string | Resource = "确定"  
  onRightClick?: () => void  
  onLeftClick?: () => void  
  dismissOnClick: boolean = true  
  build() {  
    Column() {  
  
      Blank().height(8)  
  
      if (this.title?.toString().trim() != '') {  
        Text(this.title)  
          .fontSize(18)  
          .fontColor("#FF2C2E40")  
          .fontWeight(FontWeight.Bold)  
      }  
      if (this.content?.toString()?.trim() != '') {  
        Text(this.content)  
          .fontSize(16)  
          .fontColor("#525461")  
          .margin({ top: 10 })  
      }  
  
      Row() {  
        if (this.leftBtText?.toString()?.trim() != '') {  
          Button(this.leftBtText)  
            .backgroundColor('#F6F8FC')  
            .fontColor("#2C2E40")  
            .fontSize(16)  
            .layoutWeight(1)  
            .height(49)  
            .onClick(() => {  
              if (this.dismissOnClick) {  
                this.controller.close()  
              }  
              if (this.onLeftClick) {  
                this.onLeftClick()  
              }  
            })  
        }  
        if (this.leftBtText?.toString()?.trim() != ''  
          && this.rightBtText?.toString()?.trim() != '') {  
          Blank().width(12)  
        }  
        if (this.rightBtText?.toString()?.trim() != '') {  
          Button(this.rightBtText)  
            .fontSize(16)  
            .layoutWeight(1)  
            .backgroundColor('#FF3741')  
            .fontColor(Color.White)  
            .height(49)  
            .onClick(() => {  
              if (this.dismissOnClick) {  
                this.controller.close()  
              }  
              if (this.onRightClick) {  
                this.onRightClick()  
              }  
            })  
        }  
      }  
      .margin({ top: 27 })  
    }  
    .borderRadius("20vp")  
    .backgroundColor("#ffffff")  
    .width(300)  
    .padding(16)  
  }  
}