父元素flex:1 子元素height:100%
<style>
.box{
display: flex;
flex-direction: column;
height: 100vh;
overflow: hidden; //只要不是auto
}
.parent{
flex: 1;
min-height: 0; //or height:0
}
.children{
height: 100%; //可正常继承
}
</style>
<div class="box">
<div></div>
<div class="parent">
<div class="children">
</div>
</div>
</div>