html, body {
    height: 100%;
    margin: 0;
}

body {
    display: flex;
    align-items: center;
    align-content: center;
    flex-direction: column;
    background-color: #f4f4f4;
}

.main-container {
    width:60%;
    margin: auto;
    text-align: center;
    background: white;
    padding: 2% 5%;
    flex: 1;
}

.spinner {
    display: none;
    left: 50%;
    top: 50%;
    font-size: 24px;
}