总是忘记vue怎么实现折叠面板，记录一下，没有动画样式。

 <div class="item-content padding15" style="font-size: 0.875rem;" @click="changeCollapse(index)" v-for="(item, index) in collData.dataList" :key="index" >
	<div class="flex justify-between items-center">
	  <div>
	    <span style="color: var(--fontColor);">{{ item.first }}</span>至
	    <span style="color: var(--fontColor);">{{ item.last }}</span>（8）
	  </div>
	  <el-icon v-if="collData.activeIndex.indexOf(index) != -1"><ArrowDown color="#262626" /></el-icon>
	  <el-icon v-else><ArrowRight color="#262626" /></el-icon>
	</div>
	<div class="gradient-wrapper" :class="collData.activeIndex.indexOf(index) != -1?'active':''">
	  <div class="marginT20" v-for="(org, ind) in item.orgList" :key="ind">
	    <div class="flex justify-between items-center padding10 marginB15 item-get-org">
	      <div class="item-get-name ellipsis">{{ org.name }}（{{ org.unitName }}）</div>
	      <el-icon :size="18" class="pointer"><CircleClose color="#AAAAAA" /></el-icon>
	    </div>
	  </div>
	</div>
	</div>

<script setup>
import {ref, reactive} from "vue";
const collData = reactive({
  dataList: [{
    first: 'k2',
    last: 'k12',
    orgList: [{
      name: '张三',
      unitName: '某某单位'
    }]
  },
  {
    first: 'k2',
    last: 'k12',
    orgList: [{
      name: '张三2',
      unitName: '某某单位'
    }]
  }],
  activeIndex: []
})
const changeCollapse = (index) => {
  if (collData.activeIndex.indexOf(index) == -1) {
    collData.activeIndex.push(index)
  } else {
    collData.activeIndex = collData.activeIndex.filter(item => item != index)
  }
}
</script>

<style scoped>
.item-content {
  margin: 15px 0;
  background: #f8f8f8;
  border-radius: 4px;
}
.item-unit-add {
  display: flex;
  flex-wrap: wrap;    
  padding: 10px 0;
}
.item-unit {
  padding-left: 15px;
  padding-right: 10px;
  margin: 5px;
  width: 96px;
  height: 40px;
  line-height: 40px;
  background: #F4F4F4;
  border: 1px solid #AAAAAA;
  border-radius: 4px;
  font-size: 0.875rem;
}
.item-get-org {
  background: #F4F4F4;
  border: 1px solid #AAAAAA;
  border-radius: 4px;
  font-size: 0.875rem;
}
.item-get-org:last-child {
  margin-bottom: 0;
}
.item-get-name {
  width: 80%;
}

.gradient-wrapper {
  height: 0;
  overflow: hidden;
}
.gradient-wrapper.active {
  height: 100%;
  transition: height .3s ease-in;
  transform-origin: 50% 0;
  animation: slide-down 0.3s ease-in;
  -webkit-animation: slide-down 0.3s ease-in;
}

@keyframes slide-down {
  0% {
    opacity: 0;
  }
  30% {
    opacity: .3;
  }
  60% {
    opacity: .6;
  }
  100% {
    opacity: .6;
  }
}

@-webkit-keyframes slide-down {
  0% {
    opacity: 0;
  }
  30% {
    topacity: .3;
  }
  60% {
    opacity: .6;
  }
  100% {
    opacity: .6;
  }
}
</style>