body {
    margin: 0;
    padding: 0;
}

.container {
    border: 1px solid green;
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    min-width: 250px;
    min-height: 500px;
    width: 90%;
    height: 100%;
}