body{
    font-family: 'Microsoft YaHei', sans-serif;
}

.container{
    
    width: 60%;
    border: 1px solid red;
}

.sidebar{
    position: fixed;
    top: 0;
    right: 0;

    width: 30%;
    height: 100%;

    display: flex;
    align-items: center;
    justify-content: center;

    border: 1px solid green;
}