/* Ankita Mathur - personal site
   One narrow centered column on white. Helvetica Neue throughout (system font,
   no download); the site loads no font files at all. */

/* ---- tokens ---------------------------------------------------------- */
:root {
  color-scheme: light;

  --bg: #ffffff;
  --fg: #1d1d1d;
  --body: #4a4948;
  --muted: #918e89;
  --rule: #e6e3de;
  --surface: #f5f5f5;
  --accent: #e61428;
  --btn-bg: #1a1a1a;
  --link-hover: #4a20ff; /* titles on hover; upgraded to P3 below */
  --btn-fg: #ffffff;

  --sans: "Helvetica Neue", Helvetica, Arial, sans-serif;
  --display: "Helvetica Neue", Helvetica, Arial, sans-serif;

  /* type scale (15px base): 12 / 13 / 15 / 17 / 20 / 24 */
  --t-1: 0.8rem;
  --t0: 0.8667rem;
  --t1: 1rem;
  --t2: 1.1333rem;
  --t3: 1.3333rem;
  --t4: 1.6rem;

  --col: 64rem;
  --gutter: clamp(1.25rem, 4vw, 2.5rem);
  --section-gap: 4.5rem;
  --measure: 40rem;
}

/* the hover blue is outside sRGB; show the real colour where the display can */
@supports (color: color(display-p3 1 1 1)) {
  :root {
    --link-hover: color(display-p3 0.268 0.134 0.992);
  }
}


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

html {
  font-size: 15px;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--body);
  font-family: var(--sans);
  font-weight: 400;
  font-size: var(--t1);
  line-height: 1.5;
  letter-spacing: 0;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  font-feature-settings: "kern", "liga";
  text-rendering: optimizeLegibility;
}

a {
  color: var(--body);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
  text-decoration-color: var(--rule);
}
a:hover,
a:focus-visible {
  text-decoration-color: currentColor;
}
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 2px;
}

h1,
h2,
h3 {
  font-family: var(--sans);
  margin: 0;
}

p {
  margin: 0;
  max-width: var(--measure);
}
p + p {
  margin-top: 0.9em;
}

ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.skip {
  position: absolute;
  left: -999px;
  top: 0.5rem;
  background: var(--bg);
  padding: 0.5rem 0.75rem;
}
.skip:focus {
  left: 0.5rem;
  z-index: 10;
}

/* ---- page frame -------------------------------------------------------- */
.page {
  max-width: calc(var(--col) + 2 * var(--gutter));
  margin: 0 auto;
  padding: 0 var(--gutter);
  animation: fade 320ms ease-out both;
}
@media (prefers-reduced-motion: reduce) {
  .page {
    animation: none;
  }
}
@keyframes fade {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

/* monospace uppercase labels, as in the reference */
.mono {
  font-family: var(--sans);
  font-size: 14px;
  line-height: 18px;
  font-weight: 600;
  letter-spacing: 0.24px;
  text-transform: uppercase;
  color: var(--muted);
}

/* header band: wordmark then the site links, all left-aligned, with a
   hairline that runs the full width of the viewport under it */
.top {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: 7rem;
  padding: 1.5rem 0;
  margin-bottom: 0.5rem;
}
.top nav {
  margin-left: auto;
}
.top::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 0;
  width: 100vw;
  transform: translateX(-50%);
  border-bottom: 1px solid var(--rule);
}
.top .wordmark {
  text-decoration: none;
  text-transform: none;
  letter-spacing: 0;
  font-weight: 500;
  color: var(--body);
  white-space: nowrap;
}
.top .wordmark .wave {
  font-family: "Apple Color Emoji", "Segoe UI Emoji", "Noto Color Emoji", sans-serif;
  font-weight: 400;
  margin-left: 0.15em;
}
.top nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.75rem;
  align-items: baseline;
  font-size: 14px;
  line-height: 19.5px;
}
.top nav a {
  text-decoration: none;
}
.top nav a:hover {
  text-decoration: underline;
  text-decoration-color: currentColor;
}
.top nav a[aria-current="page"] {
  color: var(--muted);
  pointer-events: none;
}

.btn {
  display: inline-block;
  background: var(--btn-bg);
  color: var(--btn-fg) !important;
  padding: 0.5em 1em;
  border-radius: 999px;
  font-weight: 500;
  line-height: 1.2;
  text-decoration: none !important;
}
.btn:hover,
.btn:focus-visible {
  background: var(--accent);
  color: #ffffff !important;
}

.bottom {
  margin-top: var(--section-gap);
  padding: 2rem 0 2.5rem;
  border-top: 1px solid var(--rule);
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.75rem;
}
.bottom .links {
  display: flex;
  flex-wrap: wrap;
  column-gap: 1.5rem;
  row-gap: 0.4rem;
  font-size: var(--t1);
}
.bottom .links a {
  text-decoration: none;
}
.bottom .links a:hover {
  text-decoration: underline;
  text-decoration-color: currentColor;
}
.bottom .meta {
  font-size: var(--t-1);
  color: var(--muted);
}

/* ---- sections ------------------------------------------------------------- */
section + section {
  margin-top: var(--section-gap);
}
.hero + section {
  margin-top: 3.25rem;
}
section > .mono {
  display: block;
  font-size: 18px;
  line-height: 18px;
  letter-spacing: 0;
  text-transform: none;
  color: var(--fg);
  margin-bottom: 1.5rem;
}
.section-intro {
  margin-bottom: 1.5rem;
}
.sub-label {
  font-size: var(--t0);
  font-weight: 500;
  color: var(--fg);
  margin: 2.25rem 0 1rem;
}
section > .mono + .sub-label,
.section-intro + .sub-label {
  margin-top: 0;
}
.section-intro + .sub-label {
  margin-top: 0.5rem;
}

/* hero: photo, then text, all left-aligned as in the reference */
.hero {
  padding-top: 2.5rem;
}
.hero .avatar {
  display: block;
  width: 10rem;
  height: 10rem;
  border-radius: 50%;
  object-fit: cover;
  margin: 0 0 1.75rem;
  box-shadow: 0 0 0 1px var(--rule);
}
.hero .byline {
  font-family: var(--display);
  font-size: 20px;
  line-height: 28px;
  font-weight: 600;
  letter-spacing: -0.22px;
  color: var(--fg);
  margin-bottom: 1.5rem;
}
.hero h1 {
  font-family: var(--display);
  font-size: 30px;
  line-height: 30px;
  font-weight: 700;
  letter-spacing: -0.22px;
  color: var(--fg);
  margin-bottom: 0.25rem;
}
.hero .intro {
  color: var(--fg);
}
.hero .intro p,
.hero .byline {
  max-width: 46rem;
}
.hero .intro p {
  font-size: 15px;
  line-height: 22px;
  color: var(--body);
}

/* rows: name | detail | date, hairline dividers; hover reveals a line more.
   Capped at the text measure so the year does not drift away from the role.
   Open on :hover (mouse; touch browsers emulate it on tap) and :focus-visible
   (keyboard). Plain :focus is deliberately not used, so a mouse click does not
   leave a row pinned open. */
.rows {
  max-width: 52rem;
}
.rows li {
  display: grid;
  grid-template-columns: 3.55rem minmax(15.5rem, 0.8fr) 1.7fr 5.4rem;
  column-gap: 0.9rem;
  align-items: center;
  padding: 0.9rem 0;
  outline-offset: -2px;
}
.rows li:focus-visible,
.dot:focus-visible {
  outline: 2px solid var(--muted);
  border-bottom: 1px solid var(--rule);
  font-size: var(--t1);
  line-height: 1.4;
}
.rows li:first-child {
  border-top: 1px solid var(--rule);
}
.rows.edu li {
  grid-template-columns: 3.55rem minmax(7rem, 1.1fr) 1.6fr 5.6rem;
}
.rows .logo {
  width: 1.6rem;
  height: 1.6rem;
  border-radius: 5px;
  object-fit: cover;
  display: block;
  filter: grayscale(1);
  opacity: 0.75;
  transition: filter 200ms ease, opacity 200ms ease;
}
.rows li:hover .logo,
.rows li:focus-visible .logo,
.rows.edu .logo {
  filter: none;
  opacity: 1;
}
.rows .more {
  grid-column: 2 / -1;
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 260ms ease;
}
.rows .more {
  color: var(--body);
}
.rows .more > span {
  min-height: 0;
  overflow: hidden;
}
.rows li:hover .more,
.rows li:focus-visible .more {
  grid-template-rows: 1fr;
  margin-top: 0.4rem;
}
@media (prefers-reduced-motion: reduce) {
  .rows .more,
  .rows .logo,
  .rows .layer {
    transition: none;
  }
}
.rows .name {
  font-weight: 500;
  color: var(--fg);
}
.rows .more {
  font-size: 15px;
  line-height: 22px;
}
.rows .detail,
.rows .when {
  color: var(--muted);
  font-weight: 400;
}
/* layer of the data stack each role sat in: a mono tag under the role,
   same vocabulary as the Explainer / Blog tags on the writing tiles */
.rows .layer {
  display: block;
  font-family: var(--sans);
  font-size: 11px;
  line-height: 16.5px;
  font-weight: 500;
  letter-spacing: 0.66px;
  text-transform: uppercase;
  color: var(--muted);
  margin-top: 0.2rem;
  transition: color 200ms ease;
}
.rows li:hover .layer,
.rows li:focus-visible .layer {
  color: var(--fg);
}
/* the small grey line that can sit under a section label */
.section-note {
  margin: -0.85rem 0 1.5rem;
  font-size: var(--t1);
  color: var(--body);
}
.rows .when {
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
  text-align: right;
}

/* recent work: two tiles */
.cards {
  display: grid;
  gap: 1.25rem;
}
.card {
  display: grid;
  grid-template-columns: 22rem minmax(0, 1fr);
  column-gap: 2.5rem;
  align-items: center;
  background: var(--surface);
  border-radius: 10px;
  padding: 1.5rem;
  text-align: left;
  box-shadow: 0 0 0 1px transparent;
  transition: box-shadow 200ms ease;
}
.card:hover {
  box-shadow: 0 0 0 1px var(--rule);
}
.card h3 {
  font-family: var(--display);
  font-size: var(--t2);
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--fg);
  margin-bottom: 0.25rem;
}
.card .sub {
  color: var(--muted);
  margin-bottom: 0.9rem;
}
.card p {
  max-width: none;
  font-size: 15px;
  line-height: 22px;
}

/* recent work: chat mock (CSS animation, loops) */
.chat {
  background: var(--bg);
  border: 1px solid var(--rule);
  border-radius: 8px;
  padding: 0.85rem;
  min-height: 11.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  font-size: var(--t-1);
  line-height: 1.4;
}
.bubble {
  max-width: 88%;
  padding: 0.5rem 0.7rem;
  border-radius: 8px;
}
.bubble.q {
  align-self: flex-end;
  background: var(--fg);
  color: #fff;
  border-bottom-right-radius: 2px;
}
.bubble.a {
  align-self: flex-start;
  background: var(--surface);
  border-bottom-left-radius: 2px;
  opacity: 0;
  animation: chat-a 9s ease-in-out infinite;
}
.bubble.a p,
.bubble.a ol {
  max-width: none;
  margin: 0;
  font-size: inherit;
  line-height: inherit;
}
.bubble.a ol {
  padding-left: 1.1rem;
  margin: 0.25rem 0 0.4rem;
}
.bubble.a li + li {
  margin-top: 0.15rem;
}
.cites i {
  display: inline-block;
  font-style: normal;
  font-family: var(--sans);
  font-size: 0.7rem;
  letter-spacing: 0.02em;
  color: var(--muted);
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 0.1rem 0.45rem;
  margin-right: 0.3rem;
}
.typed {
  display: inline-block;
  white-space: nowrap;
  overflow: hidden;
  vertical-align: bottom;
  max-width: 100%;
  animation: chat-q 9s steps(40, end) infinite;
}
@keyframes chat-q {
  0% { width: 0; }
  22% { width: 100%; }
  100% { width: 100%; }
}
@keyframes chat-a {
  0%, 30% { opacity: 0; transform: translateY(4px); }
  36%, 94% { opacity: 1; transform: none; }
  100% { opacity: 0; }
}
@media (prefers-reduced-motion: reduce) {
  .typed,
  .bubble.a {
    animation: none;
    opacity: 1;
    width: auto;
  }
}
.tools {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 0.6rem;
  margin-bottom: 1rem;
}
.card .stat {
  font-size: var(--t0);
  color: var(--muted);
  margin: 0;
  padding: 0.85rem 0 0;
  border-top: 1px solid var(--rule);
}
.card .stat b {
  display: block;
  font-family: var(--display);
  font-size: var(--t4);
  font-weight: 700;
  letter-spacing: -0.01em;
  line-height: 1.1;
  color: var(--fg);
}
.tools li {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  background: var(--bg);
  border: 1px solid var(--rule);
  border-radius: 999px;
  padding: 0.3rem 0.75rem 0.3rem 0.35rem;
  font-size: var(--t-1);
  color: var(--body);
}
.tools img {
  width: 1.35rem;
  height: 1.35rem;
  border-radius: 50%;
  object-fit: cover;
}

/* data art: 2x2 grid of pieces */
.art {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.75rem 1.5rem;
  margin-top: 2.75rem;
}
@media (max-width: 900px) {
  .art {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}
.art a {
  display: block;
  text-decoration: none;
}
/* the portrait has no wrapping link (the hotspots live inside it), so its
   title carries the link instead */
.art .title a {
  color: inherit;
  text-decoration: none;
}
.art .title a:hover,
.art .title a:focus-visible {
  color: var(--link-hover);
  text-decoration: underline;
  text-decoration-color: currentColor;
  text-underline-offset: 0.2em;
}
.art img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 740 / 555;
  object-fit: cover;
  border-radius: 6px;
  border: 1px solid var(--rule);
  transition: transform 300ms ease;
}
.art a:hover img,
.art a:focus-visible img {
  transform: scale(1.02);
}
.art .title {
  display: block;
  font-size: var(--t1);
  font-weight: 500;
  color: var(--body);
  margin-bottom: 0.5rem;
}
.art .title,
.art .title a {
  transition: color 160ms ease;
}
.art a:hover .title {
  color: var(--link-hover);
  text-decoration: underline;
  text-underline-offset: 0.2em;
}
.art .why {
  display: block;
  font-size: var(--t0);
  color: var(--muted);
  margin-top: 0.6rem;
}

/* selected writing: thumbnail left, text right, as in the reference */
.made {
  display: grid;
  row-gap: 1.75rem;
}
.made a {
  display: grid;
  grid-template-columns: 9rem minmax(0, 1fr);
  column-gap: 1.5rem;
  align-items: center;
  text-decoration: none;
}
.made img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 740 / 460;
  object-fit: cover;
  border-radius: 6px;
  border: 1px solid var(--rule);
  transition: transform 300ms ease;
}
.made a:hover img,
.made a:focus-visible img {
  transform: scale(1.02);
}
.made .title {
  display: block;
  font-size: 18px;
  font-weight: 500;
  line-height: 1.3;
  letter-spacing: -0.01em;
  color: var(--fg);
}
.made .title {
  transition: color 160ms ease;
}
.made a:hover .title,
.made a:focus-visible .title {
  color: var(--link-hover);
  text-decoration: underline;
  text-decoration-color: currentColor;
  text-underline-offset: 0.2em;
}
.made .why {
  display: block;
  color: var(--muted);
  font-size: var(--t1);
  margin-top: 0.25rem;
}

/* a year in data: portrait with hover dots */
.portrait {
  position: relative;
  border-radius: 10px;
  overflow: visible;
}
.portrait > img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 740 / 555;
  object-fit: cover;
  object-position: 44% center;
  border-radius: 6px;
  border: 1px solid var(--rule);
}
.dots {
  position: absolute;
  inset: 0;
}
.dot {
  position: absolute;
  left: var(--x);
  top: var(--y);
  width: 0.75rem;
  height: 0.75rem;
  margin: -0.375rem 0 0 -0.375rem;
  border-radius: 50%;
  background: rgba(124, 108, 214, 0.85);
  box-shadow: 0 0 0 2px rgba(124, 108, 214, 0.22);
  transition: transform 160ms ease;
}
.dot:hover,
.dot:focus {
  transform: scale(1.25);
  z-index: 2;
}
.dot .tip {
  position: absolute;
  left: 50%;
  bottom: calc(100% + 0.5rem);
  transform: translateX(-50%) translateY(4px);
  width: 8.5rem;
  background: var(--fg);
  color: #fff;
  font-size: var(--t-1);
  line-height: 1.35;
  letter-spacing: 0;
  padding: 0.3rem;
  border-radius: 8px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 160ms ease, transform 160ms ease;
}
.dot .tip img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 2;
  object-fit: cover;
  border-radius: 5px;
}
.dot .tip .cap {
  display: block;
  padding: 0.4rem 0.35rem 0.25rem;
}
.dot .tip b {
  font-weight: 600;
  margin-right: 0.35em;
}
/* dots near the top edge open downward */
.dot.below .tip {
  bottom: auto;
  top: calc(100% + 0.6rem);
  transform: translateX(-50%) translateY(-4px);
}
.dot.below .tip::after {
  top: auto;
  bottom: 100%;
  border-top-color: transparent;
  border-bottom-color: var(--fg);
}
.dot .tip::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 100%;
  margin-left: -5px;
  border: 5px solid transparent;
  border-top-color: var(--fg);
}
/* dots near the left or right edge open inwards, so the tooltip never runs
   past the image (and, on a phone, past the page) */
.dot.edge-r .tip {
  left: auto;
  right: -0.5rem;
  transform: translateY(4px);
}
.dot.edge-l .tip {
  left: -0.5rem;
  right: auto;
  transform: translateY(4px);
}
.dot.edge-r .tip::after {
  left: auto;
  right: 0.5rem;
  margin-left: 0;
}
.dot.edge-l .tip::after {
  left: 0.5rem;
  margin-left: 0;
}
.dot.edge-r:hover .tip,
.dot.edge-r:focus .tip,
.dot.edge-l:hover .tip,
.dot.edge-l:focus .tip {
  transform: translateY(0);
}
.dot:hover .tip,
.dot:focus .tip,
.dot.below:hover .tip,
.dot.below:focus .tip {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}
.section-more {
  margin-top: 1.5rem;
}
.section-more a {
  text-decoration: none;
  color: var(--fg);
}
.section-more .arrow {
  margin-left: 0.3em;
  display: inline-block;
  transition: transform 160ms ease;
}
.section-more a:hover .arrow,
.section-more a:focus-visible .arrow {
  transform: translateX(3px);
}
@media (prefers-reduced-motion: reduce) {
  .section-more .arrow {
    transition: none;
  }
}
.section-more a:hover {
  text-decoration: underline;
  text-decoration-color: currentColor;
}
@media (prefers-reduced-motion: reduce) {
  .dot,
  .dot .tip,
  .made img,
  .made .title,
  .art .title,
  .reads a,
  .card {
    transition: none;
  }
}

/* favourite things on the internet: a plain list, title then source */
.reads {
  max-width: 52rem;
  list-style: disc outside;
  padding-left: 1.1rem;
}
.reads li {
  display: list-item;
  margin-bottom: 0.6rem;
  color: var(--muted);
}
.reads li::marker {
  color: var(--muted);
}
.reads a {
  text-decoration: none;
  color: var(--fg);
}
.reads a {
  transition: color 160ms ease;
}
.reads a:hover,
.reads a:focus-visible {
  color: var(--link-hover);
  text-decoration: underline;
  text-decoration-color: currentColor;
  text-underline-offset: 0.2em;
}
.reads .src {
  font-size: var(--t0);
  color: var(--muted);
  margin-left: 0.6rem;
}

/* ---- writing page ----------------------------------------------------------- */
.prose {
  padding-top: 3.5rem;
}
.prose h1 {
  font-family: var(--display);
  font-size: var(--t4);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--fg);
  line-height: 1.2;
  margin-bottom: 1rem;
}
.prose .lede {
  color: var(--muted);
  margin-bottom: var(--section-gap);
}
.posts li {
  grid-template-columns: 1fr auto;
}
.posts a {
  text-decoration: none;
  font-weight: 500;
  color: var(--fg);
}
.posts a:hover,
.posts a:focus-visible {
  text-decoration: underline;
  text-decoration-color: currentColor;
}
.posts .src {
  font-size: var(--t0);
  color: var(--muted);
  white-space: nowrap;
}
.posts .note {
  grid-column: 1 / -1;
  font-size: var(--t1);
  color: var(--muted);
  margin-top: 0.15rem;
}

/* ---- responsive ------------------------------------------------------------- */
@media (max-width: 720px) {
  :root {
    --section-gap: 3.5rem;
  }
  .top {
    flex-wrap: wrap;
    gap: 0.75rem 2rem;
  }
  .top nav {
    margin-left: 0;
  }
  .top nav ul {
    gap: 0.5rem 1.25rem;
  }
  .hero {
    padding-top: 2rem;
  }
  .rows li {
    grid-template-columns: 3.55rem 1fr auto;
    row-gap: 0.15rem;
    font-size: var(--t1);
  }
  .rows .detail {
    grid-column: 2 / -1;
  }
  .made a {
    grid-template-columns: 1fr;
    row-gap: 0.75rem;
  }
  .card,
  .art {
    grid-template-columns: 1fr;
  }
  .card {
    row-gap: 1rem;
  }
  .hero .avatar {
    width: 8rem;
    height: 8rem;
  }
  .posts li {
    grid-template-columns: 1fr;
  }
}

.prose h2.mono {
  display: block;
  font-size: 18px;
  line-height: 18px;
  letter-spacing: 0;
  text-transform: none;
  color: var(--fg);
  margin: var(--section-gap) 0 1.5rem;
}
.prose .lede + h2.mono {
  margin-top: 0;
}