HTML CSS 垂直居中布局

display:flex;align-items:center;-webkit-box-pack:center;-webkit-justify-content:center;-ms-flex-line-pack:center;justify-content:center;-webkit-box-align:center;-webkit-align-items:center

<div style="text-align:center;height:0.3rem;text-align: center;display: flex;align-items: center;-webkit-box-pack: center;-webkit-justify-content: center;-ms-flex-line-pack: center;justify-content: center;-webkit-box-align: center;-webkit-align-items: center;">
                <style>
                    .selectLang {
                        font-size: 0.15rem;
                        border: 1px solid white;
                        color: black;
                        margin: 0 0.5rem 0 0.5rem;
                    }

                        .selectLang option {
                            color: black !important;
                        }
                </style>
                <select name="SwitchLang" class="selectLang" lay-verify="" style="
    display: inline-block;
    margin: 0 auto;
">
                    <option value="zhcn" style="color: #ffffff;">简体中文</option>
                    <option value="zhtw" style="color: #ffffff;">繁体中文</option>
                    <option value="en" style="color: #ffffff;">English</option>
                    <option value="ph" style="color: #ffffff;">Philippines</option>
                    <option value="la" style="color: #ffffff;">ເມືອງລາວ</option>
                    <option value="mas" style="color: #ffffff;">Malay</option>
                </select>
            </div>