IE11需要父母拥有flex-direction: column。
此示例旋转了按钮：
#div {
height: 200px;
width: 50px;
border: 1px solid black;
display: flex;
align-items: center;
justify-content: center;
flex-direction: column
}
#button {
height: 50px;
width: 200px;
min-width: 200px;
border: 1px solid black;
background-color: red;
transform: rotate(90deg);
}
<div id="div">
<button id="button">HELLO</button>
</div>
602392714
清零编程群