:root {
    --tab: 1.5em;
    --toc-bottom: .1em;
}

kt-part {
    display: block;
    padding-top: 1.5rem;
    margin-top: 0px;
    font-family: var(--sans-serif);
/*    font-size: 2.03rem; */     /* ladder top: 1.125^6 ... */
}

kt-chapter {
    display: block;
    padding-top: 1.5rem;
    margin-top: 0px;
    font-family: var(--sans-serif);
/*    font-size: 1.80rem;  */    /* ... 1.125^5 */

}

/*
h1 {
    padding-top: 1.5rem;
    margin-top: 0;
}


h2, h3, h4, h5 {
    padding-top: 0.25rem;
    margin-bottom: .25rem;
    padding-bottom: 0rem;
}
*/

/* The heading ladder: a modular scale, ratio 1.125 (a "major second"),
   flattening to weight below h4 -- seven visibly distinct sizes is more
   hierarchy than an eye tracks.  font-size-adjust (font.css) makes these
   steps family-independent, so the rem values are the whole truth. */
/*
h1 {
    font-size: 1.60rem;
}
h2 {
    font-size: 1.42rem;
}
h3 {
    font-size: 1.27rem;
}
h4 {
    font-size: 1.13rem;
}
h5, h6 {
    font-size: 1rem;
    font-weight: bold;
}
*/

/* Too big. How about: */

kt-part    { font-size: 1.4rem; }
kt-chapter { font-size: 1.4rem; }
h1         { font-size: 1.3rem; }
h2         { font-size: 1.2rem; }
h3         { font-size: 1.15rem; }
h4, h5, h6 { font-size: 1.125rem; }


/* Vertical space not used to indicate hierarchical level: */

kt-part, kt-chapter, h1, h2, h3, h4, h5, h6 {
    margin-top: 1.2rem;
    margin-bottom: 0.0rem;
    padding-top: 0;
    padding-bottom: 0;
}




/* Table of contents: */

.sectiontitle {
}

.sectionnumber {
    padding-right: .5rem;
}             

.level {
    font: .9em var(--sans-serif);
}

.level a:link, .level a:visited {
    color: black;
}

.level_number {
    padding-right: .5em;
}

.level1 {
    margin-left: 0;
    margin-bottom: var(--toc-bottom);
}

.level2 {
    margin-left: calc(1 * var(--tab));
    margin-bottom: var(--toc-bottom);
}

.level3 {
    margin-left: calc(2 * var(--tab));
    margin-bottom: var(--toc-bottom);
}

.level4 {
    margin-left: calc(3 * var(--tab));
    margin-bottom: var(--toc-bottom);
}

.level5 {
    margin-left: calc(4 * var(--tab));
    margin-bottom: var(--toc-bottom);
}

.level6 {
    margin-left: calc(5 * var(--tab));
    margin-bottom: var(--toc-bottom);
}