[Feature Request] loading add timer

### Existing Component
否

### Component Name
无

### Description

export default {
data() {
return {
times: 60,
show:true
}
},
methods: {
getCode() {
this.show = false
this.timer = setInterval(()=>{
this.times--
loading = ({
lock: true,
text: 'Loading' this.times,
spinner: 'el-icon-loading',
background: 'rgba(0, 0, 0, 0.7)'
// target: document.querySelector('.app-container')
})
if(this.times===0){
this.show = true
clearInterval(this.timer)
}
},1000)
}
}
}
This way to increase the timer, but the background will become very black, not transparent, can there be a solution, thank you!!!

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