@font-face {
  font-family: "jbmono";
  font-style: normal;
  font-weight: 100 800;
  font-display: swap;
  src: url("JetBrainsMono.woff2") format("woff2");
}
@font-face {
  font-family: "jbmono";
  font-style: italic;
  font-weight: 100 800;
  font-display: swap;
  src: url("JetBrainsMono-Italic.woff2") format("woff2");
}
@font-feature-values InterVariable {
  @styleset {
    alt-digits: 1;
    disambiguation: 2;
    round-quotes: 2;
  }
  @character-variant {
    cv01: 1;
    alt-one: 1;
    cv02: 2;
    alt-four: 2;
    cv03: 3;
    alt-six: 3;
    cv04: 4;
    alt-nine: 4;
    cv05: 5;
    l-tail: 5;
    cv06: 6;
    simple-u: 6;
    cv07: 7;
    alt-german-s: 7;
    cv08: 8;
    cap-i-serif: 8;
    cv09: 9;
    alt-three: 9;
    cv10: 10;
    cap-g-spur: 10;
    cv11: 11;
    simple-a: 11;
    cv12: 12;
    compact-f: 12;
    cv13: 13;
    compact-t: 13;
  }
}

:root {
  --font-size: 16px;
  --line-height: 1.5;

  --spacing: 2rem;
  --spacingv: 0.75rem; /* line-height / 2 = ((16*1.5)/2)/16 */
  --columnGap: 1rem;
  --line-width: 2px;
  --header-height: 48px;
  --row-padding: 4rem; /* .row */
  --row-padding-vertical: var(--row-padding);
  --font-family: InterVariable;

  /* font-size needed at :root for rem to work as expected */
  font-family: var(--font-family), sans-serif;
  font-synthesis: none;
  font-size: var(--font-size);
  font-feature-settings: "liga" 1, "calt" 1; /* workaround for bug in Chrome */
}

@supports not (font-variation-settings: normal) {
  :root {
    --font-family: Inter;
  }
}

/* narrow windows */
@media only screen and (max-width: 1391px) {
  /* window width <= 1391 */
  .only-huge-screen {
    display: none !important;
  }
}
@media only screen and (max-width: 719px) {
  /* window width <= 719 */
  :root {
    --row-padding: 2rem;
  }
  .only-large-screen {
    display: none !important;
  }
}
@media only screen and (max-width: 500px) {
  /* window width <= 500 */
  :root {
    --row-padding: 1rem;
    --row-padding-vertical: 2rem;
  }
  .not-small-screen {
    display: none !important;
  }
}
/* wide windows */
@media only screen and (min-width: 720px) {
  /* window width >= 720 */
  .only-small-screen {
    display: none !important;
  }
}
@media only screen and (min-width: 1392px) {
  /* window width >= 1392 */
  :root {
    font-size: calc(100vw / 87);
  }
}

body {
  line-height: var(--line-height);
  -webkit-text-size-adjust: 100%;
  -ms-text-size-adjust: 100%;
  -webkit-overflow-scrolling: touch;
  scroll-behavior: smooth;
  margin: 0;
  padding: var(--header-height) 0 0 0;
}

* {
  scroll-padding-top: var(--header-height);
}

header {
  position: sticky;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  overflow: hidden;
  z-index: 2;
  background: var(--background-color);
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: stretch;
  padding: 0;
  font-size: 14px;
}
header > div {
  width: 100%;
  /*max-width: calc(1392px - 8rem);*/
  flex: 1 0 100%;
  display: flex;
  flex-direction: row;
  align-items: stretch;
}
header > div > * {
  padding: 0 var(--row-padding);
}
header .menu {
  flex: 1 0 auto;
  display: flex;
  flex-direction: row;
  justify-content: flex-end;
  align-items: center;
  gap: 2em;
}
header h4 {
  flex: 0 0 auto;
  margin: 0;
  display: flex;
  align-items: center;
}
header a {
  padding: 0;
  text-decoration: none;
}
header a:hover {
  text-decoration: none;
  color: inherit;
}
header a.active {
  background: var(--active-bgcolor);
  padding: 4px 8px;
  margin: -4px -8px;
  border-radius: 3px;
}
header .scroll-reveal {
  pointer-events: none;
  user-select: none;
  opacity: 0;
  transition: opacity 200ms ease-in-out;
}
header .scroll-reveal.visible {
  opacity: 1;
  pointer-events: all;
}
@media only screen and (max-width: 500px) {
  /* window width <= 500 */
  header {
    position: fixed;
  }
  header .scroll-reveal {
    opacity: 1;
    pointer-events: all;
  }
  header .menu {
    gap: 8px;
  }
  header .menu > * {
    flex: 1 1 auto;
  }
}

footer {
  opacity: 0.4;
}
footer:hover {
  opacity: 1;
}

/* blocks */
div,
p,
pre,
ol,
ul,
h1,
h2,
h3,
h4,
h5,
h6 {
  margin: 0;
  padding: 0;
}
p,
pre,
ol,
ul {
  margin-bottom: calc(var(--spacingv) * 2);
}

h1 {
  font-weight: 600;
  font-size: 4rem;
  letter-spacing: -0.01em;
  line-height: 1;
  margin-left: calc(3rem / -19);
  margin-bottom: calc(var(--spacingv) * 2);
}
h2 {
  font-weight: 600;
  font-size: 2rem;
  letter-spacing: -0.01em;
  line-height: calc(var(--spacingv) * 3);
  margin-bottom: calc(var(--spacingv) * 2);
}
h3 {
  font-weight: 600;
  font-size: 1.2rem;
  /*letter-spacing: -0.018em;*/
  /*line-height: calc(var(--spacingv) * 2);*/
  margin-bottom: calc(var(--spacingv) * 2);
}
h3 q {
  font-weight: 400;
  padding-left: 0.5em;
}
h4,
h5,
h6 {
  font-weight: 640;
  margin-bottom: calc(var(--spacingv) * 1);
}

h1 > a,
h2 > a,
h3 > a,
h4 > a {
  display: inline-block;
  color: inherit;
  text-decoration: none !important;
  text-shadow: none;
  background: none;
  outline: none;
}

/* add top margin to Hn when it follows another element */
* + h1 {
  margin-top: calc(var(--spacingv) * 6);
}
* + h2 {
  margin-top: calc(var(--spacingv) * 4);
}
* + h3 {
  margin-top: calc(var(--spacingv) * 3);
}
* + h4 {
  margin-top: calc(var(--spacingv) * 2);
}

a {
  text-decoration: underline;
  word-break: break-word;
  word-wrap: break-word;
}
a.fat {
  font-weight: 500;
  color: #333;
}
a:hover {
  text-decoration: underline;
}
a.plain,
a.fat {
  background: none;
  text-shadow: none;
  text-decoration: none;
  cursor: pointer;
}
a[href^="#"]:hover {
  text-decoration-style: dashed;
}

code,
pre,
q,
tt,
r-feat,
.feat {
  font-family: jbmono, Menlo, monospace;
  font-size: 92%;
  font-feature-settings: "calt" 0;
  line-height: inherit;
  font-weight: 440;
}
code,
r-feat,
.feat {
  padding: 0 0.1em;
  white-space: pre;
}
pre {
  white-space: pre-wrap;
  line-break: loose;
  overflow-x: auto;
}
r-feat,
.feat {
  padding: 0 0.3em;
  /*margin: 0 .1em;*/
  border-radius: 0.3em;
  user-select: all;
  background: var(--unit-background-color);
}
a.feat:hover {
  text-decoration: none;
  background: var(--foreground-color);
  color: var(--background-color);
}
q {
  display: inline;
  white-space: pre-wrap;
}
q {
  display: inline;
}
q:before {
  content: "";
}
q:after {
  content: "";
}
kbd {
  -moz-font-feature-settings: "liga" 1, "calt" 1, "kern" 1, "case" 1;
  -ms-font-feature-settings: "liga" 1, "calt" 1, "kern" 1, "case" 1;
  -o-font-feature-settings: "liga" 1, "calt" 1, "kern" 1, "case" 1;
  -webkit-font-feature-settings: "liga" 1, "calt" 1, "kern" 1, "case" 1;
  font-feature-settings: "liga" 1, "calt" 1, "kern" 1, "case" 1;
  border: 1px solid rgba(0, 0, 0, 0.18);
  border-radius: 3px;
  padding: 0.1em 0.2em;
  margin: 0 0.1em;
}
dem {
  /* de-emphasize */
  font-weight: 400;
  opacity: 0.7;
}
num,
.num {
  /* number */
  letter-spacing: 0.01em;
  white-space: nowrap;
  font-variant: tabular-nums slashed-zero;
  break-before: avoid;
}
em,
i,
.italic {
  font-style: italic;
}
small,
.small {
  font-size: 1vw;
  letter-spacing: 0.012em;
}
@media only screen and (max-width: 1200px) {
  small,
  .small {
    font-size: 12px;
  }
}

hr {
  border: none;
  background: var(--foreground-color);
  /*width: 100%;*/
  height: var(--line-width);
  margin-top: calc(1em * var(--line-height));
  margin-bottom: calc(1em * var(--line-height));
}

ol,
ul {
  padding-left: 1.2rem;
}

input,
select {
  font: inherit;
}

.leading-trim {
  margin-top: -0.235em;
  line-height: 1.2;
}

.row {
  padding: var(--row-padding-vertical) var(--row-padding);
  display: flex;
  justify-content: center;
}
.row > * {
  width: 100%;
  max-width: calc(100vw - calc(var(--row-padding) * 2));
  flex: 1 0 100%;
}
.row .learn-more {
  margin-top: 2em;
  text-align: center;
  font-size: 11px;
  letter-spacing: 0.007em;
}
.row .learn-more a {
  color: rgba(0, 0, 0, 0.4);
  text-decoration-color: rgba(0, 0, 0, 0);
}
.row .learn-more a:hover {
  color: inherit;
}

.row.full-width {
  padding: 50px 0;
  justify-content: flex-start;
}
.row.full-width > * {
  max-width: initial;
}

/*
Feature helpers.

Note: font-variant-alternates:character-variant is not yet supported by
most browsers, which is why we use the "low leve" font-feature-settings
instead.
*/
.ff-none {
  font-feature-settings: "kern" 1, "calt" 0, "liga" 0, "ccmp" 0;
  -webkit-font-feature-settings: "kern" 1, "calt" 0, "liga" 0, "ccmp" 0;
  -ms-font-feature-settings: "kern" 1, "calt" 0, "liga" 0, "ccmp" 0;
  -moz-font-feature-settings: "kern" 1, "calt" 0, "liga" 0, "ccmp" 0;
}

.ff-liga,
.ff-calt {
  font-feature-settings: "liga" 1, "calt" 1;
  -webkit-font-feature-settings: "liga" 1, "calt" 1;
  -ms-font-feature-settings: "liga" 1, "calt" 1;
  -moz-font-feature-settings: "liga" 1, "calt" 1;
}
.ff-dlig {
  font-feature-settings: "kern" 1, "dlig" 1;
  -webkit-font-feature-settings: "kern" 1, "dlig" 1;
  -ms-font-feature-settings: "kern" 1, "dlig" 1;
  -moz-font-feature-settings: "kern" 1, "dlig" 1;
}
.ff-numr {
  font-feature-settings: "kern" 1, "numr" 1;
  -webkit-font-feature-settings: "kern" 1, "numr" 1;
  -ms-font-feature-settings: "kern" 1, "numr" 1;
  -moz-font-feature-settings: "kern" 1, "numr" 1;
}
.ff-dnom {
  font-feature-settings: "kern" 1, "dnom" 1;
  -webkit-font-feature-settings: "kern" 1, "dnom" 1;
  -ms-font-feature-settings: "kern" 1, "dnom" 1;
  -moz-font-feature-settings: "kern" 1, "dnom" 1;
}
.ff-tnum {
  font-feature-settings: "kern" 1, "tnum" 1;
  -webkit-font-feature-settings: "kern" 1, "tnum" 1;
  -ms-font-feature-settings: "kern" 1, "tnum" 1;
  -moz-font-feature-settings: "kern" 1, "tnum" 1;
}
.ff-case {
  font-feature-settings: "kern" 1, "case" 1;
  -webkit-font-feature-settings: "kern" 1, "case" 1;
  -ms-font-feature-settings: "kern" 1, "case" 1;
  -moz-font-feature-settings: "kern" 1, "case" 1;
}
.ff-zero {
  font-feature-settings: "kern" 1, "zero" 1;
  -webkit-font-feature-settings: "kern" 1, "zero" 1;
  -ms-font-feature-settings: "kern" 1, "zero" 1;
  -moz-font-feature-settings: "kern" 1, "zero" 1;
}
.ff-frac {
  font-feature-settings: "kern" 1, "frac" 1;
  -webkit-font-feature-settings: "kern" 1, "frac" 1;
  -ms-font-feature-settings: "kern" 1, "frac" 1;
  -moz-font-feature-settings: "kern" 1, "frac" 1;
}
.ff-sups {
  font-feature-settings: "kern" 1, "sups" 1;
  -webkit-font-feature-settings: "kern" 1, "sups" 1;
  -ms-font-feature-settings: "kern" 1, "sups" 1;
  -moz-font-feature-settings: "kern" 1, "sups" 1;
}
.ff-subs {
  font-feature-settings: "kern" 1, "subs" 1;
  -webkit-font-feature-settings: "kern" 1, "subs" 1;
  -ms-font-feature-settings: "kern" 1, "subs" 1;
  -moz-font-feature-settings: "kern" 1, "subs" 1;
}
.ff-cpsp {
  font-feature-settings: "kern" 1, "cpsp" 1;
  -webkit-font-feature-settings: "kern" 1, "cpsp" 1;
  -ms-font-feature-settings: "kern" 1, "cpsp" 1;
  -moz-font-feature-settings: "kern" 1, "cpsp" 1;
}
.ff-salt {
  font-feature-settings: "kern" 1, "salt" 1;
  -webkit-font-feature-settings: "kern" 1, "salt" 1;
  -ms-font-feature-settings: "kern" 1, "salt" 1;
  -moz-font-feature-settings: "kern" 1, "salt" 1;
}
.ff-salt-zero {
  font-feature-settings: "kern" 1, "salt" 1, "zero" 1;
}
.ff-cv07-salt-zero {
  font-feature-settings: "kern" 1, "cv07" 1, "salt" 1, "zero" 1;
}

.ff-ss01 {
  font-feature-settings: "kern" 1, "ss01" 1;
  -webkit-font-feature-settings: "kern" 1, "ss01" 1;
  -ms-font-feature-settings: "kern" 1, "ss01" 1;
  -moz-font-feature-settings: "kern" 1, "ss01" 1;
}
.ff-ss02 {
  font-feature-settings: "kern" 1, "ss02" 1;
  -webkit-font-feature-settings: "kern" 1, "ss02" 1;
  -ms-font-feature-settings: "kern" 1, "ss02" 1;
  -moz-font-feature-settings: "kern" 1, "ss02" 1;
}
.ff-ss03 {
  font-feature-settings: "kern" 1, "ss03" 1;
  -webkit-font-feature-settings: "kern" 1, "ss03" 1;
  -ms-font-feature-settings: "kern" 1, "ss03" 1;
  -moz-font-feature-settings: "kern" 1, "ss03" 1;
}
.ff-cv01 {
  font-feature-settings: "kern" 1, "cv01" 1;
  -webkit-font-feature-settings: "kern" 1, "cv01" 1;
  -ms-font-feature-settings: "kern" 1, "cv01" 1;
  -moz-font-feature-settings: "kern" 1, "cv01" 1;
}
.ff-cv02 {
  font-feature-settings: "kern" 1, "cv02" 1;
  -webkit-font-feature-settings: "kern" 1, "cv02" 1;
  -ms-font-feature-settings: "kern" 1, "cv02" 1;
  -moz-font-feature-settings: "kern" 1, "cv02" 1;
}
.ff-cv03 {
  font-feature-settings: "kern" 1, "cv03" 1;
  -webkit-font-feature-settings: "kern" 1, "cv03" 1;
  -ms-font-feature-settings: "kern" 1, "cv03" 1;
  -moz-font-feature-settings: "kern" 1, "cv03" 1;
}
.ff-cv04 {
  font-feature-settings: "kern" 1, "cv04" 1;
  -webkit-font-feature-settings: "kern" 1, "cv04" 1;
  -ms-font-feature-settings: "kern" 1, "cv04" 1;
  -moz-font-feature-settings: "kern" 1, "cv04" 1;
}
.ff-cv05 {
  font-feature-settings: "kern" 1, "cv05" 1;
  -webkit-font-feature-settings: "kern" 1, "cv05" 1;
  -ms-font-feature-settings: "kern" 1, "cv05" 1;
  -moz-font-feature-settings: "kern" 1, "cv05" 1;
}
.ff-cv06 {
  font-feature-settings: "kern" 1, "cv06" 1;
  -webkit-font-feature-settings: "kern" 1, "cv06" 1;
  -ms-font-feature-settings: "kern" 1, "cv06" 1;
  -moz-font-feature-settings: "kern" 1, "cv06" 1;
}
.ff-cv07 {
  font-feature-settings: "kern" 1, "cv07" 1;
  -webkit-font-feature-settings: "kern" 1, "cv07" 1;
  -ms-font-feature-settings: "kern" 1, "cv07" 1;
  -moz-font-feature-settings: "kern" 1, "cv07" 1;
}
.ff-cv08 {
  font-feature-settings: "kern" 1, "cv08" 1;
  -webkit-font-feature-settings: "kern" 1, "cv08" 1;
  -ms-font-feature-settings: "kern" 1, "cv08" 1;
  -moz-font-feature-settings: "kern" 1, "cv08" 1;
}
.ff-cv09 {
  font-feature-settings: "kern" 1, "cv09" 1;
  -webkit-font-feature-settings: "kern" 1, "cv09" 1;
  -ms-font-feature-settings: "kern" 1, "cv09" 1;
  -moz-font-feature-settings: "kern" 1, "cv09" 1;
}
.ff-cv10 {
  font-feature-settings: "kern" 1, "cv10" 1;
  -webkit-font-feature-settings: "kern" 1, "cv10" 1;
  -ms-font-feature-settings: "kern" 1, "cv10" 1;
  -moz-font-feature-settings: "kern" 1, "cv10" 1;
}
.ff-cv11 {
  font-feature-settings: "kern" 1, "cv11" 1;
  -webkit-font-feature-settings: "kern" 1, "cv11" 1;
  -ms-font-feature-settings: "kern" 1, "cv11" 1;
  -moz-font-feature-settings: "kern" 1, "cv11" 1;
}

.button,
a.button {
  font: inherit;
  display: inline-block;
  padding: 0.25rem 0.8rem;
  margin: 0.5rem 0;
  border: none;
  border-radius: 6px;
  text-decoration: none;
  user-select: none;
  font-weight: 470;
  letter-spacing: 0.02em;
  background: var(--foreground-color);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  flex: 0 1 auto;
}
.button:hover,
a.button:hover {
  background: var(--link-hover-color);
}

#sponsor-button {
  display: inline-block;
  min-width: 1%;
  max-width: 100%;
  height: 2em;
  line-height: 2em;
  border-radius: 0.25em;
  border: 1px solid var(--underline-color);
  font-weight: 500;
  font-weight: 480;
  text-decoration: none;
  padding: 0 0.6em;
  user-select: none;
  -webkit-user-select: none;
}
#sponsor-button:hover {
  color: inherit;
}
#sponsor-button span {
  display: flex;
  align-items: center;
  white-space: nowrap;
}
#sponsor-button span::before {
  content: "♥";
  margin-right: 0.3em;
  font-size: 1.1em;
  line-height: 1em;
}

.cv01 {
  font-variant-alternates: character-variant(cv01);
}
.cv02 {
  font-variant-alternates: character-variant(cv02);
}
.cv03 {
  font-variant-alternates: character-variant(cv03);
}
.cv04 {
  font-variant-alternates: character-variant(cv04);
}
.cv05 {
  font-variant-alternates: character-variant(cv05);
}
.cv06 {
  font-variant-alternates: character-variant(cv06);
}
.cv07 {
  font-variant-alternates: character-variant(cv07);
}
.cv08 {
  font-variant-alternates: character-variant(cv08);
}
.cv09 {
  font-variant-alternates: character-variant(cv09);
}
.cv10 {
  font-variant-alternates: character-variant(cv10);
}
.cv11 {
  font-variant-alternates: character-variant(cv11);
}
.cv12 {
  font-variant-alternates: character-variant(cv12);
}
.cv13 {
  font-variant-alternates: character-variant(cv13);
}
.zero {
  font-variant-numeric: slashed-zero;
}

/* Raster grid subsystem (rsms.me/raster) */
r-grid {
  display: grid;
  --grid-tc: repeat(4, 1fr);
  grid-template-columns: var(--grid-tc);
  --grid-cs: 1; /* column start */
  --grid-ce: -1; /* column end */
  grid-column-gap: var(--columnGap);
  grid-row-gap: 0;
}


r-grid > r-cell.spacer {
  grid-column: 1 / -1;
  height: calc(var(--spacingv) * 2);
}
@media only screen and (max-width: 719px) {
  r-grid {
    grid-column-gap: 1rem;
  }
  r-cell.spacer {
    height: calc(var(--spacingv) * 3);
  }
}
r-grid > hr {
  grid-column: 1 / -1;
  width: 100%;
}

/* r-cell -- cell or column */
r-grid > r-cell {
  display: block;
  appearance: none;
  -webkit-appearance: none;
}

r-grid[columns="1"] {
  --grid-tc: repeat(1, 1fr);
}
r-grid[columns="2"] {
  --grid-tc: repeat(2, 1fr);
}
r-grid[columns="3"] {
  --grid-tc: repeat(3, 1fr);
}
r-grid[columns="4"] {
  --grid-tc: repeat(4, 1fr);
}
r-grid[columns="5"] {
  --grid-tc: repeat(5, 1fr);
}
r-grid[columns="6"] {
  --grid-tc: repeat(6, 1fr);
}
r-grid[columns="7"] {
  --grid-tc: repeat(7, 1fr);
}
r-grid[columns="8"] {
  --grid-tc: repeat(8, 1fr);
}

/* span=start... */
r-grid > r-cell[span^="1"] {
  --grid-cs: 1;
}
r-grid > r-cell[span^="2"] {
  --grid-cs: 2;
}
r-grid > r-cell[span^="3"] {
  --grid-cs: 3;
}
r-grid > r-cell[span^="4"] {
  --grid-cs: 4;
}
r-grid > r-cell[span^="5"] {
  --grid-cs: 5;
}
r-grid > r-cell[span^="6"] {
  --grid-cs: 6;
}
r-grid > r-cell[span^="7"] {
  --grid-cs: 7;
}
r-grid > r-cell[span^="8"] {
  --grid-cs: 8;
}

/* span=...+width, span=...-end */
r-grid > r-cell[span$="+1"],
r-grid > r-cell[span="1"] {
  --grid-ce: 1;
}
r-grid > r-cell[span$="+2"],
r-grid > r-cell[span$="-1"],
r-grid > r-cell[span="2"] {
  --grid-ce: 2;
}
r-grid > r-cell[span$="+3"],
r-grid > r-cell[span$="-2"],
r-grid > r-cell[span="3"] {
  --grid-ce: 3;
}
r-grid > r-cell[span$="+4"],
r-grid > r-cell[span$="-3"],
r-grid > r-cell[span="4"] {
  --grid-ce: 4;
}
r-grid > r-cell[span$="+5"],
r-grid > r-cell[span$="-4"],
r-grid > r-cell[span="5"] {
  --grid-ce: 5;
}
r-grid > r-cell[span$="+6"],
r-grid > r-cell[span$="-5"],
r-grid > r-cell[span="6"] {
  --grid-ce: 6;
}
r-grid > r-cell[span$="+7"],
r-grid > r-cell[span$="-6"],
r-grid > r-cell[span="7"] {
  --grid-ce: 7;
}
r-grid > r-cell[span$="+8"],
r-grid > r-cell[span$="-7"],
r-grid > r-cell[span="8"] {
  --grid-ce: 8;
}
r-grid > r-cell[span$="-8"] {
  --grid-ce: 9;
}

/* connect vars */
r-grid > r-cell[span] {
  grid-column-end: span var(--grid-ce);
}
r-grid > r-cell[span*="+"],
r-grid > r-cell[span*="-"],
r-grid > r-cell[span*=".."] {
  grid-column-start: var(--grid-cs);
}
r-grid > r-cell[span*="-"],
r-grid > r-cell[span*=".."] {
  grid-column-end: var(--grid-ce);
}
r-grid > r-cell[span="row"] {
  grid-column: 1 / -1;
}

@media only screen and (max-width: 719px) {
  r-grid[columns-s="1"] {
    --grid-tc: repeat(1, 1fr);
  }
  r-grid[columns-s="2"] {
    --grid-tc: repeat(2, 1fr);
  }
  r-grid[columns-s="3"] {
    --grid-tc: repeat(3, 1fr);
  }
  r-grid[columns-s="4"] {
    --grid-tc: repeat(4, 1fr);
  }
  r-grid[columns-s="5"] {
    --grid-tc: repeat(5, 1fr);
  }
  r-grid[columns-s="6"] {
    --grid-tc: repeat(6, 1fr);
  }
  r-grid[columns-s="7"] {
    --grid-tc: repeat(7, 1fr);
  }
  r-grid[columns-s="8"] {
    --grid-tc: repeat(8, 1fr);
  }

  /* span-s=start... */
  r-grid > r-cell[span-s^="1"] {
    --grid-cs: 1;
  }
  r-grid > r-cell[span-s^="2"] {
    --grid-cs: 2;
  }
  r-grid > r-cell[span-s^="3"] {
    --grid-cs: 3;
  }
  r-grid > r-cell[span-s^="4"] {
    --grid-cs: 4;
  }
  r-grid > r-cell[span-s^="5"] {
    --grid-cs: 5;
  }
  r-grid > r-cell[span-s^="6"] {
    --grid-cs: 6;
  }
  r-grid > r-cell[span-s^="7"] {
    --grid-cs: 7;
  }
  r-grid > r-cell[span-s^="8"] {
    --grid-cs: 8;
  }

  /* span-s=...+width, span-s=...-end */
  r-grid > r-cell[span-s$="+1"],
  r-grid > r-cell[span-s="1"] {
    --grid-ce: 1;
  }
  r-grid > r-cell[span-s$="+2"],
  r-grid > r-cell[span-s$="-1"],
  r-grid > r-cell[span-s="2"] {
    --grid-ce: 2;
  }
  r-grid > r-cell[span-s$="+3"],
  r-grid > r-cell[span-s$="-2"],
  r-grid > r-cell[span-s="3"] {
    --grid-ce: 3;
  }
  r-grid > r-cell[span-s$="+4"],
  r-grid > r-cell[span-s$="-3"],
  r-grid > r-cell[span-s="4"] {
    --grid-ce: 4;
  }
  r-grid > r-cell[span-s$="+5"],
  r-grid > r-cell[span-s$="-4"],
  r-grid > r-cell[span-s="5"] {
    --grid-ce: 5;
  }
  r-grid > r-cell[span-s$="+6"],
  r-grid > r-cell[span-s$="-5"],
  r-grid > r-cell[span-s="6"] {
    --grid-ce: 6;
  }
  r-grid > r-cell[span-s$="+7"],
  r-grid > r-cell[span-s$="-6"],
  r-grid > r-cell[span-s="7"] {
    --grid-ce: 7;
  }
  r-grid > r-cell[span-s$="+8"],
  r-grid > r-cell[span-s$="-7"],
  r-grid > r-cell[span-s="8"] {
    --grid-ce: 8;
  }
  r-grid > r-cell[span-s$="-8"] {
    --grid-ce: 9;
  }

  /* connect vars */
  r-grid > r-cell[span-s] {
    grid-column-end: span var(--grid-ce);
  }
  r-grid > r-cell[span-s*="+"],
  r-grid > r-cell[span-s*="-"],
  r-grid > r-cell[span-s*=".."] {
    grid-column-start: var(--grid-cs);
  }
  r-grid > r-cell[span-s*="-"],
  r-grid > r-cell[span-s*=".."] {
    grid-column-end: var(--grid-ce);
  }
  r-grid > r-cell[span-s="row"] {
    grid-column: 1 / -1;
  }
}

/* for window width >= 1392 */
@media only screen and (min-width: 1392px) {
  r-grid[columns-l="1"] {
    --grid-tc: repeat(1, 1fr);
  }
  r-grid[columns-l="2"] {
    --grid-tc: repeat(2, 1fr);
  }
  r-grid[columns-l="3"] {
    --grid-tc: repeat(3, 1fr);
  }
  r-grid[columns-l="4"] {
    --grid-tc: repeat(4, 1fr);
  }
  r-grid[columns-l="5"] {
    --grid-tc: repeat(5, 1fr);
  }
  r-grid[columns-l="6"] {
    --grid-tc: repeat(6, 1fr);
  }
  r-grid[columns-l="7"] {
    --grid-tc: repeat(7, 1fr);
  }
  r-grid[columns-l="8"] {
    --grid-tc: repeat(8, 1fr);
  }

  /* span-l=start... */
  r-grid > r-cell[span-l^="1"] {
    --grid-cs: 1;
  }
  r-grid > r-cell[span-l^="2"] {
    --grid-cs: 2;
  }
  r-grid > r-cell[span-l^="3"] {
    --grid-cs: 3;
  }
  r-grid > r-cell[span-l^="4"] {
    --grid-cs: 4;
  }
  r-grid > r-cell[span-l^="5"] {
    --grid-cs: 5;
  }
  r-grid > r-cell[span-l^="6"] {
    --grid-cs: 6;
  }
  r-grid > r-cell[span-l^="7"] {
    --grid-cs: 7;
  }
  r-grid > r-cell[span-l^="8"] {
    --grid-cs: 8;
  }

  /* span-l=...+width, span-l=...-end */
  r-grid > r-cell[span-l$="+1"],
  r-grid > r-cell[span-l="1"] {
    --grid-ce: 1;
  }
  r-grid > r-cell[span-l$="+2"],
  r-grid > r-cell[span-l$="-1"],
  r-grid > r-cell[span-l="2"] {
    --grid-ce: 2;
  }
  r-grid > r-cell[span-l$="+3"],
  r-grid > r-cell[span-l$="-2"],
  r-grid > r-cell[span-l="3"] {
    --grid-ce: 3;
  }
  r-grid > r-cell[span-l$="+4"],
  r-grid > r-cell[span-l$="-3"],
  r-grid > r-cell[span-l="4"] {
    --grid-ce: 4;
  }
  r-grid > r-cell[span-l$="+5"],
  r-grid > r-cell[span-l$="-4"],
  r-grid > r-cell[span-l="5"] {
    --grid-ce: 5;
  }
  r-grid > r-cell[span-l$="+6"],
  r-grid > r-cell[span-l$="-5"],
  r-grid > r-cell[span-l="6"] {
    --grid-ce: 6;
  }
  r-grid > r-cell[span-l$="+7"],
  r-grid > r-cell[span-l$="-6"],
  r-grid > r-cell[span-l="7"] {
    --grid-ce: 7;
  }
  r-grid > r-cell[span-l$="+8"],
  r-grid > r-cell[span-l$="-7"],
  r-grid > r-cell[span-l="8"] {
    --grid-ce: 8;
  }
  r-grid > r-cell[span-l$="-8"] {
    --grid-ce: 9;
  }

  /* connect vars */
  r-grid > r-cell[span-l] {
    grid-column-end: span var(--grid-ce);
  }
  r-grid > r-cell[span-l*="+"],
  r-grid > r-cell[span-l*="-"],
  r-grid > r-cell[span-l*=".."] {
    grid-column-start: var(--grid-cs);
  }
  r-grid > r-cell[span-l*="-"],
  r-grid > r-cell[span-l*=".."] {
    grid-column-end: var(--grid-ce);
  }
  r-grid > r-cell[span-l="row"] {
    grid-column: 1 / -1;
  }
}

/* .debug can be added to a r-grid to visualize its effective cells */
r-grid.debug > * {
  --color: rgba(248, 110, 91, 0.3);
  background-image: linear-gradient(
    to bottom,
    var(--color) 0%,
    var(--color) 100%
  );
}
r-grid.debug > :nth-child(6n + 2) {
  --color: rgba(103, 126, 208, 0.3);
}
r-grid.debug > :nth-child(6n + 3) {
  --color: rgba(224, 174, 72, 0.3);
}
r-grid.debug > :nth-child(6n + 4) {
  --color: rgba(77, 214, 115, 0.3);
}
r-grid.debug > :nth-child(6n + 5) {
  --color: rgba(217, 103, 219, 0.3);
}
r-grid.debug > :nth-child(6n + 6) {
  --color: rgba(94, 204, 211, 0.3);
}
r-grid.debug > :nth-child(6n + 7) {
  --color: rgba(248, 110, 91, 0.3);
}

[contenteditable] {
  outline: none;
}

:root.debug *:nth-child(4n) {
  outline: 1px solid rgba(0, 0, 255, 0.5);
}
:root.debug *:nth-child(4n + 1) {
  outline: 1px solid rgba(0, 255, 255, 0.5);
}
:root.debug *:nth-child(4n + 2) {
  outline: 1px solid rgba(255, 0, 255, 0.5);
}
:root.debug *:nth-child(4n + 3) {
  outline: 1px solid rgba(255, 0, 0, 0.5);
}