在 CSS 中，如何优雅地隐藏并列布局中的右侧面板而不挤压其内容？

<template>
  <div class="about">
    <div class="lft">
      <button @click="() => isshowright = !isshowright">显示/隐藏</button>
    </div>
    <div class="rht" :class="!isshowright ? 'closed' : ''">
      <div>隐藏右侧区块后，这些内容怎么不隐藏，还会受到挤压？</div>
    </div>
  </div>
</template>

<script>
export default {
  name: '',
  data() {
    return {
      isshowright: true
    }
  },
  methods: {

  }
}
</script>

<style lang='css' scoped>
.about{
  height: 100%;
  width: 100%;
  display: flex;
}
.lft, .rht{
  height: 100%;
}
.lft{
  flex: 1;
  background: #e3e3e3;
}
.rht{
  transition: all 3s;
  width: 400px;
  background: rgb(201, 186, 186);
}
.closed{
  overflow: hidden;
  width: 0;
}
</style>

<div class="detail-area" :class="!isshowdetailpanel ? 'closed' : ''">
  <div class="detail-content">
    ...
  </div>
</div>

.detail-area{
  width: 350px;
  height: 100%;
  background: $bg-block;
  transition: all $delay;
  margin-left: 2px;
  box-sizing: border-box;
  display: flex;
  position: relative;
  &.closed{
    width: 0;
  }
  .detail-content{
    padding: 10px;
    box-sizing: border-box;
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    white-space: nowrap;
  }
}