.main-container {
    margin: 20px 20px;
}

.left_column {
    text-align: center;
}

.content_holder {
    flex-grow: 1;
    text-align: center;
    display: flex;
    justify-content: center;
}

.content {
    text-align: left;
    margin: 0 auto;
    min-width: 300px;
    max-width: 1200px;
    min-height: 80vh;
}
		
.right_column {
    text-align: center;
}	

/*
.footer {
    position: absolute;
    bottom: -1000px;
    width: 100%;
    text-align: center;
}
*/

@media screen and (max-width: 600px) {

    .left_column {
        display: none;
    }

    .right_column {
        display: none;
    }

    .content {
        margin: 3px 5px;
    } 

    .footer {
        display: none;
    }

    .a_holder {
        display: none;
    }
}