$header-height: 5.6rem; $footer-height: 14.65rem;

html, body {

height: 100%;

}

main {

min-height: 100%;
margin-top: -$header-height;
margin-bottom: -$footer-height;

&:before, &:after {
    content: '';
    display: block;
}

&:before {
    height: $header-height;
}

&:after {
    height: $footer-height;
}

}