/* Constellation project page */

:root {
  /* Night palette, taken from the Constellation logo */
  --night: #081533;
  --night-2: #0c1f47;
  --night-line: rgba(142, 197, 255, 0.22);
  --glow: #4d9dff;
  --glow-soft: #8ec5ff;
  --on-night: #ffffff;
  --on-night-2: #c6d5ef;
  --on-night-3: #93a8cc;

  /* Paper palette */
  --paper: #ffffff;
  --paper-2: #f5f7fb;
  --ink: #111827;
  --ink-2: #2b3342;
  --ink-3: #5a6377;
  --line: #e1e6ef;
  --accent: #1a5fd0;
  --accent-ink: #0f4bb0;
  --accent-wash: #eaf1ff;

  --serif: "Source Serif 4", "Source Serif Pro", Georgia, "Times New Roman", serif;
  --sans: "IBM Plex Sans", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --wrap: 1120px;
  --gutter: 24px;
  --radius: 12px;
  --overlap: clamp(40px, 9vw, 140px);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink-2);
  font-family: var(--sans);
  font-size: 1.0625rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img,
video {
  max-width: 100%;
}

a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  text-decoration-color: rgba(26, 95, 208, 0.35);
  transition: color 0.15s ease, text-decoration-color 0.15s ease;
}

a:hover {
  color: var(--accent-ink);
  text-decoration-color: currentColor;
}

:focus-visible {
  outline: 2px solid var(--glow);
  outline-offset: 3px;
  border-radius: 4px;
}

strong {
  color: var(--ink);
  font-weight: 600;
}

.wrap {
  width: 100%;
  max-width: calc(var(--wrap) + 2 * var(--gutter));
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.icon {
  width: 1.05em;
  height: 1.05em;
  flex: none;
}


/* ---------- Hero ---------- */

.hero {
  position: relative;
  overflow: hidden;
  color: var(--on-night);
  background:
    radial-gradient(900px 520px at 82% 8%, rgba(46, 104, 214, 0.38), transparent 70%),
    radial-gradient(700px 420px at 8% 30%, rgba(46, 104, 214, 0.16), transparent 70%),
    linear-gradient(180deg, var(--night) 0%, var(--night-2) 100%);
  padding-bottom: calc(var(--overlap) + 56px);
}

/* Starfield: two offset tiles so the pattern does not visibly repeat */
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    radial-gradient(1px 1px at 18px 26px, rgba(255, 255, 255, 0.7), transparent),
    radial-gradient(1px 1px at 92px 140px, rgba(255, 255, 255, 0.45), transparent),
    radial-gradient(1.5px 1.5px at 160px 60px, rgba(190, 220, 255, 0.8), transparent),
    radial-gradient(1px 1px at 210px 190px, rgba(255, 255, 255, 0.35), transparent),
    radial-gradient(1px 1px at 58px 212px, rgba(255, 255, 255, 0.5), transparent),
    radial-gradient(1px 1px at 132px 18px, rgba(255, 255, 255, 0.3), transparent),
    radial-gradient(1px 1px at 44px 96px, rgba(255, 255, 255, 0.25), transparent),
    radial-gradient(1.5px 1.5px at 300px 120px, rgba(255, 255, 255, 0.55), transparent),
    radial-gradient(1px 1px at 250px 300px, rgba(190, 220, 255, 0.5), transparent),
    radial-gradient(1px 1px at 350px 330px, rgba(255, 255, 255, 0.35), transparent);
  background-size: 240px 240px, 240px 240px, 240px 240px, 240px 240px, 240px 240px, 240px 240px, 240px 240px,
    370px 370px, 370px 370px, 370px 370px;
  opacity: 0.8;
}

.hero__art {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

.topbar {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding-top: 20px;
  padding-bottom: 20px;
}

.topbar__brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--on-night);
  font-family: var(--serif);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: 0.01em;
  text-decoration: none;
}

.topbar__brand:hover {
  color: var(--on-night);
}

.topbar__mark {
  width: 30px;
  height: 30px;
  flex: none;
  overflow: visible;
}

.topbar__links {
  display: flex;
  gap: 4px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.topbar__links a {
  display: block;
  padding: 6px 12px;
  border-radius: 999px;
  color: var(--on-night-2);
  font-size: 0.9rem;
  text-decoration: none;
}

.topbar__links a:hover {
  color: var(--on-night);
  background: rgba(255, 255, 255, 0.08);
}

.hero__body {
  position: relative;
  text-align: center;
  padding-top: clamp(40px, 7vw, 84px);
}

.venue {
  display: inline-flex;
  align-items: center;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  padding: 5px 14px 5px 5px;
  border: 1px solid var(--night-line);
  border-radius: 999px;
  background: rgba(77, 157, 255, 0.08);
  color: var(--on-night-2);
  font-size: 0.875rem;
  line-height: 1.4;
  text-decoration: none;
  transition: background 0.15s ease, border-color 0.15s ease;
}

.venue:hover {
  color: var(--on-night);
  background: rgba(77, 157, 255, 0.16);
  border-color: rgba(142, 197, 255, 0.45);
}

.venue__tag {
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--glow);
  color: var(--night);
  font-family: var(--mono);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.02em;
}

.venue__oa {
  position: relative;
  padding-left: 12px;
  color: var(--glow-soft);
}

.venue__oa::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 4px;
  height: 4px;
  margin-top: -2px;
  border-radius: 50%;
  background: var(--on-night-3);
}

.hero__title {
  margin: 28px 0 0;
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(2.6rem, 7vw, 4.75rem);
  line-height: 1.02;
  letter-spacing: -0.025em;
  font-variation-settings: "opsz" 60;
  text-wrap: balance;
}

.hero__subtitle {
  max-width: 760px;
  margin: 14px auto 0;
  color: var(--on-night-2);
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(1.2rem, 2.4vw, 1.65rem);
  line-height: 1.3;
  letter-spacing: -0.01em;
  text-wrap: balance;
}

.authors {
  max-width: 820px;
  margin: 32px auto 0;
  color: var(--on-night-3);
  font-size: 1rem;
  line-height: 1.8;
  text-wrap: balance;
}

.authors a {
  color: var(--on-night);
  white-space: nowrap;
  text-decoration-color: rgba(255, 255, 255, 0.25);
}

.authors a:hover {
  color: var(--glow-soft);
  text-decoration-color: currentColor;
}

.affiliation {
  margin: 6px 0 0;
  color: var(--on-night-3);
  font-size: 0.95rem;
}

.affiliation + .affiliation {
  margin-top: 0;
}

.affiliation a {
  color: var(--on-night-2);
  text-decoration-color: rgba(255, 255, 255, 0.2);
}

.affiliation a:hover {
  color: var(--glow-soft);
  text-decoration-color: currentColor;
}

.affiliation__sep {
  margin: 0 6px;
}

.affiliation__group {
  white-space: nowrap;
}

.affiliation__paren {
  white-space: nowrap;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  margin-top: 32px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 42px;
  padding: 0 18px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.06);
  color: var(--on-night);
  font-size: 0.95rem;
  font-weight: 500;
  text-decoration: none;
  transition: background 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
}

.btn:hover {
  color: var(--on-night);
  background: rgba(255, 255, 255, 0.13);
  border-color: rgba(255, 255, 255, 0.34);
}

.btn--primary {
  background: #1f6ae0;
  border-color: #1f6ae0;
}

.btn--primary:hover {
  background: #1f6ae0;
  border-color: var(--glow-soft);
  box-shadow: 0 0 0 4px rgba(77, 157, 255, 0.22), 0 0 28px rgba(77, 157, 255, 0.45);
}


/* ---------- Teaser ---------- */

.teaser {
  position: relative;
  margin-top: calc(-1 * var(--overlap));
}

.teaser video {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 1;
  object-fit: cover;
  border-radius: var(--radius);
  background: var(--night-2);
  box-shadow:
    0 0 0 1px rgba(8, 21, 51, 0.08),
    0 12px 24px -12px rgba(8, 21, 51, 0.35),
    0 40px 80px -32px rgba(8, 21, 51, 0.55);
}

.teaser figcaption {
  max-width: 80ch;
}

.teaser + .section {
  margin-top: 56px;
  border-top: 0;
  padding-top: 32px;
}


/* ---------- Sections ---------- */

.section {
  padding: 88px 0;
  border-top: 1px solid var(--line);
  scroll-margin-top: 0;
}

.section--tint {
  background: var(--paper-2);
}

.section__grid {
  display: grid;
  grid-template-columns: 210px minmax(0, 1fr);
  column-gap: 56px;
  row-gap: 40px;
}

.section__grid > * {
  grid-column: 2;
}

.section__grid > .section__label {
  grid-column: 1;
  grid-row: 1;
}

.section__label {
  position: sticky;
  top: 28px;
  align-self: start;
  margin: 0;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1.75rem;
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.015em;
}

.prose {
  max-width: 68ch;
}

.prose p {
  margin: 0 0 1.1em;
  text-wrap: pretty;
}

.prose > :last-child {
  margin-bottom: 0;
}

.subsection > * + * {
  margin-top: 24px;
}

.subsection > h3 {
  margin: 0;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1.3rem;
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.01em;
}

.subsection > h3 + p {
  margin-top: 8px;
}

.subsection > p {
  max-width: 68ch;
  margin-bottom: 0;
  text-wrap: pretty;
}

.subsection > p + .figure,
.subsection > p + .table-figure {
  margin-top: 32px;
}


/* ---------- Figures ---------- */

.figure {
  margin: 0;
}

.figure img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.figure figcaption,
.table-figure figcaption {
  color: var(--ink-3);
  font-size: 0.9rem;
  line-height: 1.5;
  text-align: left;
}

.figure figcaption {
  margin-top: 12px;
}

.figure figcaption strong,
.table-figure figcaption strong {
  color: var(--ink-2);
}

.section__grid > .figure--wide {
  grid-column: 1 / -1;
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 40px;
  align-items: start;
}


/* ---------- Tables (booktabs style: top, mid and bottom rules) ---------- */

.table-figure {
  margin: 0;
}

.table-figure figcaption {
  margin-bottom: 10px;
}

.table-scroll {
  position: relative;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.table {
  width: 100%;
  border-collapse: collapse;
  border-top: 1.5px solid var(--ink);
  border-bottom: 1.5px solid var(--ink);
  font-size: 0.925rem;
  line-height: 1.45;
  font-variant-numeric: lining-nums tabular-nums;
}

.table th,
.table td {
  padding: 6px 14px;
  color: var(--ink-2);
  font-weight: 400;
  text-align: left;
  vertical-align: baseline;
}

.table th:first-child,
.table td:first-child {
  padding-left: 0;
}

.table th:last-child,
.table td:last-child {
  padding-right: 0;
}

.table thead {
  border-bottom: 1px solid var(--ink);
}

.table thead th {
  padding-top: 8px;
  color: var(--ink);
  font-weight: 600;
  white-space: nowrap;
  vertical-align: bottom;
}

/* cmidrule under a column-group header */
.table thead th.group {
  padding-bottom: 4px;
  text-align: center;
  background: linear-gradient(var(--ink-3), var(--ink-3)) center bottom / calc(100% - 20px) 1px no-repeat;
}

.table tbody + tbody {
  border-top: 1px solid var(--line);
}

.table tr.subhead th {
  padding-top: 10px;
  padding-bottom: 2px;
  color: var(--ink-3);
  font-size: 0.85rem;
  font-style: italic;
}

.table tbody tr:last-child th,
.table tbody tr:last-child td {
  padding-bottom: 10px;
}

.table tbody tr:first-child th,
.table tbody tr:first-child td {
  padding-top: 8px;
}

.table tfoot {
  border-top: 1px solid var(--ink);
}

.table tfoot th,
.table tfoot td {
  padding-top: 8px;
  padding-bottom: 8px;
  color: var(--ink);
  font-weight: 600;
}

.table .num {
  text-align: right;
  white-space: nowrap;
}

.table b {
  color: var(--ink);
  font-weight: 600;
}

.table .pm {
  color: var(--ink-3);
  font-size: 0.85em;
}

.table .backend {
  display: block;
  color: var(--ink-3);
  font-size: 0.8rem;
}

.table .nw {
  white-space: nowrap;
}

.table .dl {
  text-align: right;
  white-space: nowrap;
}

.table--compact {
  max-width: 600px;
}

.table--summary th {
  padding-right: 24px;
  color: var(--ink-3);
  white-space: nowrap;
}

.table--summary td {
  color: var(--ink);
}

.table-view {
  margin-top: 16px;
}

.table-view summary {
  width: fit-content;
  color: var(--accent);
  font-size: 0.9rem;
  cursor: pointer;
}

.table-view[open] summary {
  margin-bottom: 14px;
}


/* ---------- Dot plot ---------- */

.dotplot {
  --label-w: 210px;
  --pad-r: 14px;
  --ped: #2a78d6;
  --veh: #eb6834;
  --surface: var(--paper);
  --grid: #e8ebf1;
  position: relative;
  font-size: 0.875rem;
}

.dotplot__legend {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 22px;
  margin: 0 0 4px var(--label-w);
  color: var(--ink-2);
  font-size: 0.85rem;
}

.dotplot__legend > span {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.dotplot__body {
  position: relative;
}

.dotplot__grid {
  position: absolute;
  top: 0;
  bottom: 0;
  left: var(--label-w);
  right: var(--pad-r);
  pointer-events: none;
}

.dotplot__grid span {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 1px;
  margin-left: -0.5px;
  background: var(--grid);
}

.dotplot__group {
  position: relative;
  width: fit-content;
  margin-top: 12px;
  padding: 2px 10px 2px 0;
  background: var(--surface);
  color: var(--ink-3);
  font-size: 0.8rem;
  font-style: italic;
}

.dotplot__row {
  position: relative;
  display: grid;
  grid-template-columns: var(--label-w) minmax(0, 1fr);
  align-items: center;
  min-height: 28px;
}

.dotplot__label {
  padding-right: 16px;
  color: var(--ink-2);
  line-height: 1.3;
}

.dotplot__row.is-ref .dotplot__label {
  color: var(--ink);
  font-weight: 600;
}

.dotplot__track {
  position: relative;
  align-self: stretch;
  min-height: 28px;
  margin-right: var(--pad-r);
}

.dotplot__span {
  position: absolute;
  top: 50%;
  height: 2px;
  margin-top: -1px;
  border-radius: 1px;
  background: #c9d0db;
}

.dot {
  position: absolute;
  top: 50%;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  box-shadow: 0 0 0 2px var(--surface);
  transform: translate(-50%, -50%);
  transition: transform 0.12s ease;
}

/* 24px hit area around a 10px mark */
.dot::before {
  content: "";
  position: absolute;
  inset: -7px;
  border-radius: 50%;
}

.dot--ped {
  background: var(--ped);
}

.dot--veh {
  background: var(--veh);
}

.dot[tabindex]:hover,
.dot[tabindex]:focus-visible {
  outline: none;
  transform: translate(-50%, -50%) scale(1.35);
}

.dot[tabindex]:focus-visible {
  box-shadow: 0 0 0 2px var(--surface), 0 0 0 3.5px var(--ink-2);
}

.dotplot__legend .dot {
  position: static;
  display: inline-block;
  box-shadow: none;
  transform: none;
}

.dotplot__value {
  position: absolute;
  top: 50%;
  color: var(--ink);
  font-size: 0.8rem;
  font-weight: 600;
  line-height: 1;
  transform: translate(calc(-100% - 10px), -50%);
  pointer-events: none;
}

.dotplot__axis {
  position: relative;
  height: 24px;
  margin: 4px var(--pad-r) 0 var(--label-w);
  border-top: 1px solid #c3c9d4;
}

.dotplot__axis span {
  position: absolute;
  top: 5px;
  color: var(--ink-3);
  font-size: 0.75rem;
  font-variant-numeric: tabular-nums;
  transform: translateX(-50%);
}

.dotplot__axis-title {
  margin: 2px var(--pad-r) 0 var(--label-w);
  color: var(--ink-3);
  font-size: 0.8rem;
  text-align: center;
}

.dotplot__tip {
  position: absolute;
  z-index: 5;
  padding: 6px 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  box-shadow: 0 8px 24px -8px rgba(17, 24, 39, 0.25);
  font-size: 0.8rem;
  line-height: 1.4;
  white-space: nowrap;
  transform: translate(-50%, calc(-100% - 12px));
  pointer-events: none;
}

.dotplot__tip strong {
  display: block;
  color: var(--ink);
  font-size: 0.95rem;
}

.dotplot__tip .key {
  display: inline-block;
  width: 10px;
  height: 2px;
  margin-right: 6px;
  border-radius: 1px;
  vertical-align: middle;
}

.dotplot__tip .model {
  display: block;
  color: var(--ink-3);
}


/* ---------- Download ---------- */

.download h3 {
  margin: 0 0 8px;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 1.2rem;
  font-weight: 600;
}

.download p {
  margin: 0 0 10px;
}

.download__license {
  color: var(--ink-3);
  font-size: 0.9rem;
}


/* ---------- Citation ---------- */

.reference {
  color: var(--ink-2);
}

.bibtex {
  overflow: hidden;
  border-radius: var(--radius);
  background: var(--night);
  box-shadow: 0 0 0 1px rgba(8, 21, 51, 0.1);
}

.bibtex__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 8px 8px 18px;
  border-bottom: 1px solid rgba(142, 197, 255, 0.14);
  color: var(--on-night-3);
  font-family: var(--mono);
  font-size: 0.8rem;
  letter-spacing: 0.04em;
}

.copy {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  min-height: 32px;
  padding: 0 12px;
  border: 1px solid rgba(142, 197, 255, 0.22);
  border-radius: 999px;
  background: transparent;
  color: var(--on-night-2);
  font: 500 0.85rem var(--sans);
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.copy:hover {
  color: var(--on-night);
  background: rgba(255, 255, 255, 0.08);
}

.copy .icon--check,
.copy.is-copied .icon--copy {
  display: none;
}

.copy.is-copied .icon--check {
  display: block;
}

.copy.is-copied {
  color: #7ee0a8;
  border-color: rgba(126, 224, 168, 0.4);
}

.bibtex pre {
  margin: 0;
  padding: 18px;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  color: #dbe7fb;
  font-family: var(--mono);
  font-size: 0.82rem;
  line-height: 1.7;
  tab-size: 2;
}


/* ---------- Footer ---------- */

.footer {
  padding: 40px 0 56px;
  border-top: 1px solid var(--line);
  color: var(--ink-3);
  font-size: 0.85rem;
}

.footer__inner p {
  max-width: 80ch;
  margin: 0 0 6px;
}

.footer a {
  color: var(--ink-2);
}


/* ---------- Responsive ---------- */

@media (max-width: 960px) {
  .section__grid {
    grid-template-columns: minmax(0, 1fr);
    row-gap: 28px;
  }

  .section__grid > *,
  .section__grid > .section__label,
  .section__grid > .figure--wide {
    grid-column: 1;
    grid-row: auto;
  }

  .section__label {
    position: static;
  }
}

@media (max-width: 800px) {
  .affiliation__group {
    display: block;
    white-space: normal;
  }

  .affiliation__sep {
    display: none;
  }
}

@media (max-width: 720px) {
  :root {
    --gutter: 16px;
  }

  body {
    font-size: 1rem;
  }

  .topbar__links {
    display: none;
  }

  .venue__name {
    display: none;
  }

  .actions {
    gap: 8px;
  }

  .btn {
    min-height: 40px;
    padding: 0 14px;
    font-size: 0.9rem;
  }

  .teaser video {
    border-radius: 8px;
  }

  .section {
    padding: 64px 0;
  }

  .split {
    grid-template-columns: minmax(0, 1fr);
    gap: 36px;
  }

  .table {
    font-size: 0.875rem;
  }

  .table th,
  .table td {
    padding-left: 8px;
    padding-right: 8px;
  }

  .dotplot {
    --label-w: 124px;
    --pad-r: 10px;
  }

  .dotplot__label {
    padding-right: 10px;
    font-size: 0.78rem;
  }

  .dotplot__legend {
    margin-left: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  * {
    transition: none !important;
  }
}