css弹窗动画效果，示例弹窗从底部弹出

从底部弹出来，有过渡动画效果

用max-height可以自适应内容的高度，当内容会超过最大高度时可以在弹窗里加个scroll-view
弹窗不能用v-if来隐藏，不然transition没效果，transition只能对已有dom元素起效果，所以用透明和visibility来隐藏

<view @tap="showpop">弹出来</view>

<view class="popWai" :class="isshowpop?'popWaiAc':''" @tap="closepop">
	<view class="popNei" :style="isshowpop?'bottom:0':'bottom:-680rpx'">
		<div>发顺丰萨芬撒</div>
	</view>
</view>

data(){
	return{
		isshowpop:false,
	}
},
methods:{
	showpop(){
		this.isshowpop = true;
	},
	closepop(){
		this.isshowpop = false;
	},
}

.popWai{
	position: fixed;
	top: 0;
	left: 0;
	background-color: rgba(0, 0, 0, 0.5);
	width: 100%;
	height: 100%;
	z-index: 99;
	opacity: 0;
	visibility: hidden;
	overflow: hidden;
}
.popNei{
	position: absolute;
	left: 0;
	width: 100%;
	max-height: 680rpx;
	background-color: #fff;
	transition: all 0.5s ease-out;
}
.popWaiAc {
	opacity: 1;
	visibility: visible;
}