body * {
    box-sizing: border-box;
}
body {
    font-family: PingFangSC-Regular, Roboto, Helvetica Neue, Helvetica, Tahoma,
    Arial, PingFang SC-Light, Microsoft YaHei;
}
button {
    margin: 0;
    padding: 0;
    border: 1px solid transparent;
    outline: none;
    background-color: transparent;
}

button:active {
    opacity: 0.6;
}
.flex-col {
    display: flex;
    flex-direction: column;
}
.flex-row {
    display: flex;
    flex-direction: row;
}