/* heading elements */
h1 {
    font-size: 2em;
    font-weight: bold;
}

:is(article, aside, nav, section) h1 {
    font-size: 1.5em;
}

:is(article, aside, nav, section) :is(article, aside, nav, section) h1 {
    font-size: 1.17em;
}

:is(article, aside, nav, section) :is(article, aside, nav, section) :is(article, aside, nav, section) h1 {
    font-size: 1.00em;
}

h2 {
    font-size: 1.5em;
    font-weight: bold;
}

h3 {
    font-size: 1.17em;
    font-weight: bold;
}

h4 {
    font-size: 1.00em;
    font-weight: bold;
}

h5 {
    font-size: 0.83em;
    font-weight: bold;
}

h6 {
    font-size: 0.67em;
    font-weight: bold;
}