/* Notebook theme: a ruled school copy with a double red margin and blue
   ballpoint. Every vertical measure is a multiple of --l so that text sits on
   the rules; elements of arbitrary height carry .snap and site.js pads them to
   the next rule. Theme: <html data-theme="light|dark"> is set before paint by
   the inline snippet in each page's <head>. Font sizes (--fs-*) and the line
   spacing (--l) come from FONT_SIZES in tools/build.py, written into each
   page's <head>. */

/* Google Sans: Latin in the main files; Cyrillic and Devanagari in a file that
   only downloads on pages that set them in body text. */
@font-face {
  font-display: swap;
  font-family: 'Google Sans';
  font-weight: 400;
  src: url(fonts/google-sans-400.woff2) format('woff2');
  unicode-range: U+0000-03FF, U+1E00-1EFF, U+2000-22FF, U+FB00-FB06;
}

@font-face {
  font-display: swap;
  font-family: 'Google Sans';
  font-weight: 400;
  src: url(fonts/google-sans-400-extra.woff2) format('woff2');
  unicode-range: U+0400-04FF, U+0900-097F, U+200C-200D, U+25CC;
}

@font-face {
  font-display: swap;
  font-family: 'Google Sans';
  font-weight: 600;
  src: url(fonts/google-sans-600.woff2) format('woff2');
  unicode-range: U+0000-03FF, U+1E00-1EFF, U+2000-22FF, U+FB00-FB06;
}

@font-face {
  font-display: swap;
  font-family: 'Google Sans';
  font-style: italic;
  font-weight: 400;
  src: url(fonts/google-sans-italic-400.woff2) format('woff2');
  unicode-range: U+0000-03FF, U+1E00-1EFF, U+2000-22FF, U+FB00-FB06;
}

@font-face {
  font-display: swap;
  font-family: 'Caveat';
  font-weight: 400;
  src: url(fonts/caveat-400.woff2) format('woff2');
}

@font-face {
  font-display: swap;
  font-family: 'Caveat';
  font-weight: 700;
  src: url(fonts/caveat-700.woff2) format('woff2');
}

/* Caveat has no Devanagari; Kalam fills in for it, scaled down to sit beside
   Caveat's small x-height. */
@font-face {
  font-display: swap;
  font-family: 'Kalam';
  font-weight: 400;
  size-adjust: 80%;
  src: url(fonts/kalam-400.woff2) format('woff2');
  unicode-range: U+0900-097F, U+200C-200D, U+25CC;
}

@font-face {
  font-display: swap;
  font-family: 'Kalam';
  font-weight: 700;
  size-adjust: 80%;
  src: url(fonts/kalam-700.woff2) format('woff2');
  unicode-range: U+0900-097F, U+200C-200D, U+25CC;
}

@font-face {
  /* Only the Devanagari numerals that key the margin notes. */
  font-display: swap;
  font-family: 'Tiro Devanagari Sanskrit';
  src: url(fonts/tiro-devanagari-numerals.woff2) format('woff2');
  unicode-range: U+0966-096F;
}

:root {
  --paper: #fbfcfe;
  --rule: #c9d6ee;
  --margin: #e06a6a;
  --text: #1c1f26;
  --ink: #1e3fa0;
  --mark: #f0c93a;
  --muted: #5f677a;
  --red: #c73232;
  --body: 'Google Sans', system-ui, sans-serif;
  --hand: 'Caveat', 'Kalam', 'Comic Sans MS', cursive;
  --deva: 'Tiro Devanagari Sanskrit', 'Kalam', serif;
  --mono: ui-monospace, 'SF Mono', Menlo, Consolas, monospace;
  color-scheme: light;
}

/* Light is the default regardless of the system setting; dark applies only
   when the reader picks it with the toggle. */
:root[data-theme='dark'] {
  --paper: #14171e;
  --rule: #232c3d;
  --margin: #8f3d44;
  --text: #dde2ec;
  --ink: #95b0ff;
  --mark: #b8962e;
  --muted: #98a0b0;
  --red: #ff8a80;
  color-scheme: dark;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

/* The rules belong to the whole window, edge to edge; .page only adds the red
   margin. */
html {
  -webkit-text-size-adjust: 100%;
  background: var(--paper) repeating-linear-gradient(
    transparent 0 calc(var(--l) - 1px),
    var(--rule) 0 var(--l));
  background-position: 0 calc(var(--l) * 2 - 7px);
}

body {
  color: var(--text);
  font: var(--fs-body)/var(--l) var(--body);
  margin: 0;
}

img {
  display: block;
  height: auto;
  max-width: 100%;
}

a {
  color: var(--ink);
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
}

a:hover {
  text-decoration-style: wavy;
}

:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 3px;
}

.skip {
  left: -999px;
  position: absolute;
}

.skip:focus {
  background: var(--paper);
  left: 16px;
  padding: 0 8px;
  top: 8px;
  z-index: 60;
}

/* The page: double red margin line after the margin column, running the full
   window height. */
.page {
  --mw: 13.5rem;
  background: linear-gradient(
    90deg,
    transparent calc(var(--mw) + 24px),
    var(--margin) 0 calc(var(--mw) + 25.5px),
    transparent 0 calc(var(--mw) + 29px),
    var(--margin) 0 calc(var(--mw) + 30.5px),
    transparent 0);
  margin: 0 auto;
  max-width: 62rem;
  min-height: 100vh;
  padding: calc(var(--l) * 2) 24px calc(var(--l) * 2) 0;
  position: relative;
}

.row {
  column-gap: 56px;
  display: grid;
  grid-template-columns: var(--mw) minmax(0, 38rem);
}

.row > .main {
  grid-column: 2;
  grid-row: 1;
  min-width: 0;
}

.row > .margin {
  grid-column: 1;
  grid-row: 1;
  padding-left: 16px;
  text-align: right;
}

p,
ul,
ol,
dl,
pre,
figure,
h1,
h2,
h3 {
  margin: 0 0 var(--l);
}

ul {
  padding-left: 1.3em;
}

h1 {
  color: var(--ink);
  font: 700 var(--fs-title)/calc(var(--l) * 2) var(--hand);
  text-decoration: underline double;
  text-decoration-thickness: 1px;
  text-underline-offset: 9px;
}

h2 {
  color: var(--ink);
  font: 700 var(--fs-heading)/var(--l) var(--hand);
  margin-top: var(--l);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 7px;
}

.row:has(> .main > h1) + .row h2 {
  margin-top: 0;
}

h3 {
  font: 600 var(--fs-entry-title)/var(--l) var(--body);
}

.mono {
  font: var(--fs-mono)/var(--l) var(--mono);
}

/* Date / page box, top right — filled in by hand at build time. */
.dp {
  color: var(--muted);
  display: flex;
  font: italic var(--fs-date-label)/1 var(--body);
  gap: 14px;
  position: absolute;
  right: 24px;
  top: 14px;
}

.dp span {
  border-bottom: 1px solid var(--muted);
  min-width: 4.6em;
  padding: 0 4px 2px;
}

.dp b {
  color: var(--ink);
  font: 400 var(--fs-date) var(--hand);
  margin-left: 6px;
}

/* Header and sidebar. Below the wide breakpoint: the name label on About, one
   handwritten line elsewhere, then the nav. Above it: label and nav in the
   sidebar. */
.side .label {
  display: none;
  margin-bottom: 12px;
}

.is-about .side .label {
  display: grid;
}

.is-about .head {
  display: none;
}

.label {
  background: var(--paper);
  border: 1.5px solid var(--ink);
  border-radius: 14px;
  column-gap: 24px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  outline: 1px solid var(--ink);
  outline-offset: 4px;
  padding: 0 22px;
}

.label dl {
  column-gap: 12px;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  margin: 0;
}

.label dt {
  align-self: end;
  color: var(--muted);
  font: italic var(--fs-label-key)/var(--l) var(--body);
}

.label dt[lang] {
  font: var(--fs-label-key-deva)/var(--l) var(--hand);
}

.label dd {
  border-bottom: 1px dotted var(--muted);
  color: var(--ink);
  font: 400 var(--fs-label-value)/var(--l) var(--hand);
  margin: 0;
}

.label dd a {
  color: inherit;
}

.label .label-name {
  color: var(--ink);
  font: 700 var(--fs-label-name)/calc(var(--l) * 2) var(--hand);
  margin: 0;
  text-decoration: none;
}

.photo {
  align-self: start;
  margin: 18px 4px 0;
  position: relative;
  transform: rotate(2deg);
  transition: transform .3s;
  width: 10.8rem;
}

/* Easter egg: the swapped photo (site.js) is taped on at a different angle. */
.photo.swapped {
  transform: rotate(-3deg);
}

@media (prefers-reduced-motion: reduce) {
  .photo {
    transition: none;
  }
}

.photo img {
  border: 6px solid #fff;
  box-shadow: 0 1px 3px #0003;
}

.photo::before,
.photo::after {
  /* Tape. */
  background: #e9dfb8b3;
  box-shadow: 0 1px 1px #0001;
  content: '';
  height: 18px;
  position: absolute;
  top: -7px;
  width: 58px;
}

.photo::before {
  left: -16px;
  transform: rotate(-32deg);
}

.photo::after {
  right: -16px;
  transform: rotate(30deg);
}

.who {
  font: 700 var(--fs-who)/calc(var(--l) * 2) var(--hand);
  margin: 0;
}

.who a {
  color: var(--ink);
  text-decoration: none;
}

.who .deva {
  font-size: var(--fs-who-deva);
  font-weight: 400;
  margin-left: .35em;
}

.who a:hover {
  text-decoration: underline wavy;
  text-decoration-thickness: 1px;
}

[data-theme-toggle] {
  background: none;
  border: 0;
  color: var(--ink);
  cursor: pointer;
  font: var(--fs-toggle)/var(--l) var(--hand);
  padding: 0 .1em;
}

.when-dark {
  display: none;
}

:root[data-theme='dark'] .when-dark {
  display: inline;
}

:root[data-theme='dark'] .when-light {
  display: none;
}

/* Margin notes, keyed to the text by Devanagari numerals. Pointing at either
   end lights both (site.js). */
.margin {
  color: var(--ink);
  font: var(--fs-notes)/var(--l) var(--hand);
}

.margin .note {
  margin: 0;
}

.n,
.nref {
  color: var(--red);
  font-family: var(--deva);
  font-style: normal;
  text-decoration: none;
}

.n {
  font-size: var(--fs-note-numeral);
  margin-right: 2px;
}

sup {
  line-height: 0;
}

.nref {
  font-size: var(--fs-note-ref);
  margin-left: 1px;
  padding: 0 2px;
}

.lit,
.note:target {
  background: color-mix(in srgb, var(--mark) 38%, transparent);
  border-radius: 3px;
}

/* Entries: a paper, a course, a talk. */
.entry {
  margin: 0 0 var(--l);
}

.entry > * {
  margin: 0;
}

.meta {
  color: var(--muted);
  font-style: italic;
}

.me {
  font-weight: 600;
}

.links {
  font: var(--fs-links)/var(--l) var(--mono);
}

.links a,
.links del {
  margin-right: .8em;
}

del {
  color: var(--muted);
}

/* Scholar, GitHub, LinkedIn and email: under the nav graph (in the sidebar on
   wide screens). */
.contacts {
  align-items: center;
  column-gap: .8em;
  display: flex;
  flex-wrap: wrap;
}

.contacts .mono {
  flex-basis: 100%;
}

/* Sketched icons: each outline is drawn twice, the second pass slightly off,
   like a pen going over it again. */
.icon {
  align-items: center;
  color: var(--ink);
  display: inline-flex;
  height: var(--l);
  transition: transform .2s;
}

.icon:hover {
  transform: rotate(-8deg);
}

.icon svg {
  fill: none;
  height: 30px;
  overflow: visible;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.7;
  width: 30px;
}

.icon .again {
  opacity: .45;
  stroke-width: 1.2;
  transform: translate(.7px, .5px) rotate(1deg);
  transform-origin: center;
}

@media (prefers-reduced-motion: reduce) {
  .icon {
    transition: none;
  }

  .icon:hover {
    transform: none;
  }
}

.redirecting {
  color: var(--muted);
  list-style: none;
  padding: 0;
}

pre.key {
  font: var(--fs-key-block)/calc(var(--l) / 2) var(--mono);
  overflow-x: auto;
}

embed.pdf {
  border: 1.5px solid var(--text);
  display: block;
  height: calc(var(--l) * 25);
  width: 100%;
}

footer .shloka {
  color: var(--muted);
  font: var(--fs-footer-shloka)/var(--l) var(--hand);
}

footer .colophon {
  color: var(--muted);
  font: var(--fs-footer)/var(--l) var(--hand);
}

/* Nav graph. By default (phones, no JS) the links are a row of hand-drawn
   boxes. Wider than a phone, site.js draws the graph (.cfg-ready) and places
   each link on its box using data-box, in the drawing's viewBox units. */
.cfg {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem .6rem;
  margin: 0 0 var(--l);
  max-width: 46rem;
  position: relative;
}

.cfg a {
  border: 1.5px solid var(--text);
  border-radius: 2px 6px 3px 5px;
  color: var(--text);
  font-family: var(--hand);
  font-size: var(--fs-nav);
  line-height: 1.9;
  padding: 0 .75em;
  text-decoration: none;
}

.cfg a[aria-current] {
  background: color-mix(in srgb, var(--mark) 35%, transparent);
}

.cfg-ink {
  display: none;
}

@media (min-width: 761px) {
  .cfg-ready {
    aspect-ratio: var(--ar, 700 / 210);
    display: block;
  }

  .cfg-ready a {
    background: none;
    border: 0;
    display: grid;
    height: var(--box-height);
    left: var(--box-left);
    line-height: var(--l);
    padding: 0;
    place-items: center;
    position: absolute;
    top: var(--box-top);
    width: var(--box-width);
  }

  .cfg-ready a:hover {
    color: var(--ink);
  }

  .cfg-ready .cfg-ink {
    display: block;
    height: 100%;
    inset: 0;
    overflow: visible;
    position: absolute;
    width: 100%;
  }
}

.cfg-ink path {
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.cfg-box {
  opacity: .85;
  stroke: var(--text);
  stroke-width: 1.3;
}

.cfg-edge {
  stroke: var(--ink);
  stroke-width: 1.2;
}

.cfg-fill {
  opacity: .55;
  stroke: var(--mark);
  stroke-width: 2.6;
}

.cfg-phi-dot {
  fill: var(--ink);
}

.cfg-ink text {
  fill: var(--ink);
  font-family: var(--hand);
  font-size: var(--fs-nav-doodle);
}

.cfg-ink .cfg-phi {
  font-family: var(--mono);
  font-size: var(--fs-nav-phi);
}

/* Ink trailer: a drop of ink follows the pointer and, over a link, writes what
   it is. */
#ink {
  left: 0;
  opacity: 0;
  pointer-events: none;
  position: fixed;
  top: 0;
  transition: opacity .3s;
  z-index: 50;
}

#ink.on {
  opacity: 1;
}

#ink::before {
  background: var(--ink);
  border-radius: 52% 48% 55% 45% / 47% 55% 45% 53%;
  content: '';
  height: 10px;
  left: -5px;
  position: absolute;
  top: -5px;
  transition: transform .25s;
  width: 10px;
}

#ink.open::before {
  transform: scale(2.1) rotate(25deg);
}

#ink span {
  color: var(--ink);
  font: var(--fs-cursor)/1 var(--hand);
  left: 18px;
  opacity: 0;
  position: absolute;
  top: 6px;
  transform: translateY(4px) rotate(-4deg);
  transition: opacity .2s, transform .2s;
  white-space: nowrap;
}

#ink.open span {
  opacity: 1;
  transform: translateY(0) rotate(-4deg);
}

@media (hover: none), (prefers-reduced-motion: reduce) {
  #ink {
    display: none;
  }
}

/* BibTeX dialog */
.bib {
  background: var(--paper);
  border: 1.5px solid var(--ink);
  border-radius: 10px;
  color: var(--text);
  max-height: 80vh;
  padding: 0;
  width: min(760px, 92vw);
}

.bib::backdrop {
  background: #0008;
}

.bib header {
  align-items: baseline;
  border-bottom: 1px solid var(--rule);
  display: flex;
  gap: 12px;
  padding: 8px 16px;
}

.bib h2 {
  flex: 1;
  font-size: var(--fs-bib-title);
  margin: 0;
  text-decoration: none;
}

.bib pre {
  font: var(--fs-bib-code)/1.5 var(--mono);
  margin: 0;
  max-height: 60vh;
  overflow: auto;
  padding: 12px 16px;
  white-space: pre-wrap;
}

.bib button {
  background: none;
  border: 1px solid var(--ink);
  border-radius: 4px;
  color: var(--ink);
  cursor: pointer;
  font: var(--fs-bib-button) var(--hand);
  padding: 0 10px;
}

@media (max-width: 760px) {
  .page {
    --mw: 0px;
    background-position: -10px 0;
    padding-left: 40px;
    padding-right: 18px;
  }

  .row {
    grid-template-columns: minmax(0, 1fr);
  }

  .row > .main,
  .row > .margin {
    grid-column: 1;
    grid-row: auto;
  }

  .row > .margin {
    margin: calc(var(--l) * -1) 0 var(--l);
    padding: 0;
    text-align: left;
  }

  /* Dates and labels read before their entry. */
  .row > .margin.lead {
    margin: 0;
    order: -1;
  }

  .who {
    margin-bottom: var(--l);
  }

  .who .deva {
    display: block;
    line-height: var(--l);
    margin: 0;
  }

  .label {
    grid-template-columns: minmax(0, 1fr);
    padding: 0 14px;
  }

  .label .label-name {
    font-size: var(--fs-label-name-small);
  }

  .photo {
    margin: 8px 0 var(--l) 6px;
    width: 10.2rem;
  }

  .dp {
    right: 18px;
  }
}

/* Wide landscape screens: notes run down the left edge of the window, and the
   label, nav, date box and lamp sit in a fixed sidebar on the right of every
   page. (site.js switches the nav drawing on the same query.) */
@media (min-width: 1200px) and (orientation: landscape) {
  .page {
    --side: 25rem;
    margin: 0;
    max-width: none;
    padding-right: calc(var(--side) + 40px);
  }

  .head {
    display: none;
  }

  .side {
    background: var(--paper);
    border-left: 1.5px solid var(--rule);
    bottom: 0;
    display: flex;
    flex-direction: column;
    gap: 16px;
    overflow-y: auto;
    padding: 72px 28px 24px;
    position: fixed;
    right: 0;
    top: 0;
    width: var(--side);
    z-index: 5;
  }

  .side > .main,
  .side > .margin {
    padding: 0;
    text-align: left;
  }

  .side .label {
    display: grid;
    grid-template-columns: minmax(0, 1fr);
    margin: 0 0 24px !important;
  }

  .side .photo {
    margin: 20px auto 8px;
    order: -1;
    width: 10.8rem;
  }

  .side .label .label-name {
    font-size: var(--fs-label-name-small);
  }

  .side .cfg {
    margin: 0 !important;
    max-width: none;
  }

  .side .contacts {
    margin: 20px 0 0;
  }

  .side .cfg-ready a {
    font-size: var(--fs-nav-sidebar);
  }

  .side .dp {
    right: 28px;
    top: 18px;
  }
}