Elastic Headers and Text

@media screen and (min-width: 320px) {
    h1 {
        font-size: calc(32px + 6 * ((100vw - 320px) / 680));
    }

    h2 {
        font-size: calc(24px + 6 * ((100vw - 320px) / 680));
    }

    h3 {
        font-size: calc(18.72px + 6 *((100vw - 320px) / 680))
    }

    h4 {
        font-size: calc(16px + 6 *((100vw - 320px) / 680))
    }

    h5 {
        font-size: calc(13.28px + 6 *((100vw - 320px) / 680))
    }

    h6 {
        font-size: calc(12px + 6 *((100vw - 320px) / 680))
    }

    html {
        font-size: calc(16px + 6 * ((100vw - 320px) / 680));
    }
}