body {
    background-color: black;
}

#main_wrapper {
}

#content {
    width: 800px;
    margin: auto;
    margin-top: 8%;
}

#rect {
}

.rect {
    
}

.rect2:hover {
    background-color: #f3f3f3;
    transition: 1s;
}

.rect1 {
    border: 16px solid #f3f3f3; /* Light grey */
    border-radius: 0%;
    width: 400px;
    height: 400px;
    margin-top: 20px;
    margin-right: auto;
    margin-left: auto;
    animation: spin linear infinite;
}

.rect2 {
    border: 16px solid #f3f3f3; /* Light grey */
    border-radius: 0%;
    width: 100px;
    height: 100px;
    margin-top: 20px;
    animation: spin 2s linear infinite;
    margin-right: auto;
    margin-left: auto;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}