:root {
  --paper:   #fbfbfc;
  --raised:  #ffffff;
  --ink:     #12161d;
  --muted:   #5f6a7a;
  --rule:    #dfe3e9;
  --accent:  #0b5fa5;
  --sans: "IBM Plex Sans", ui-sans-serif, system-ui, "Helvetica Neue", Arial, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, "SFMono-Regular", Menlo, Consolas, monospace;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper:  #0e1116;
    --raised: #141922;
    --ink:    #e7eaef;
    --muted:  #98a3b3;
    --rule:   #262d38;
    --accent: #74b4e8;
  }
}
:root[data-theme="dark"] {
  --paper:  #0e1116;
  --raised: #141922;
  --ink:    #e7eaef;
  --muted:  #98a3b3;
  --rule:   #262d38;
  --accent: #74b4e8;
}

body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
.page {
  max-width: 44rem;
  margin: 0 auto;
  padding-inline: 20px;
  padding-block: clamp(40px, 9vw, 96px) 64px;
  display: flex;
  flex-direction: column;
  gap: clamp(44px, 7vw, 72px);
}

a { color: var(--accent); text-underline-offset: 3px; text-decoration-thickness: 1px; }
a:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 2px; }

/* masthead */
.masthead { display: grid; gap: 14px; }
.masthead-text { display: grid; gap: 14px; }
.hero { margin: 8px 0 0; width: min(100%, 320px); display: grid; gap: 8px; }
.hero video {
  width: 100%;
  height: auto;
  aspect-ratio: 1;
  display: block;
  background: #000033;
  border: 1px solid var(--rule);
  border-radius: 3px;
}
@media (min-width: 640px) {
  .masthead:has(.hero) { grid-template-columns: minmax(0, 1fr) 208px; column-gap: 32px; align-items: start; }
  .hero { margin: 0; width: 100%; }
}
h1 {
  font-size: clamp(2rem, 6.5vw, 2.9rem);
  line-height: 1.08;
  font-weight: 600;
  letter-spacing: -0.02em;
  text-wrap: balance;
  margin: 0;
}
.lede { margin: 0; max-width: 34em; color: var(--muted); font-size: 1.0625rem; }
.lede strong { color: var(--ink); font-weight: 500; }

/* research areas */
h2 {
  font-size: 0.72rem;
  font-family: var(--mono);
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 22px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--rule);
}
.areas { display: grid; gap: 0; }
.area { padding-block: 16px; border-bottom: 1px solid var(--rule); }
.area:last-child { border-bottom: 0; }
.area > summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: baseline;
  gap: 10px;
}
.area-head { display: grid; gap: 2px; }
.area-title { font-weight: 600; letter-spacing: -0.005em; }
.area > summary::-webkit-details-marker { display: none; }
.area > summary::before {
  content: "+";
  font-family: var(--mono);
  font-weight: 400;
  color: var(--muted);
  width: 0.8em;
}
.area[open] > summary::before { content: "\2212"; }
.area > summary:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 2px; }
.area-note { color: var(--muted); }
.pub-list {
  list-style: none;
  margin: 16px 0 4px;
  padding: 0 0 0 calc(0.8em + 10px);
  display: grid;
  gap: 14px;
}
.pub-list li { display: grid; gap: 2px; }
.pub-list p { margin: 0; color: var(--muted); font-size: 0.9375rem; }
.meta { font-family: var(--mono); font-size: 0.78rem; color: var(--muted); }
.pub-links { font-family: var(--mono); font-size: 0.78rem; color: var(--muted); }

/* software */
.repos { display: grid; gap: 14px; }
.repo {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 3px;
  padding: 16px 18px;
  background: var(--raised);
  border: 1px solid var(--rule);
  border-radius: 3px;
}
.repo > a { font-family: var(--mono); font-weight: 500; font-size: 1rem; }
.repo a { overflow-wrap: anywhere; }
.repo p { margin: 0; color: var(--muted); font-size: 0.9375rem; }
.repo em { font-style: italic; }
.repo .install {
  margin-top: 6px;
  font-size: 0.875rem;
  color: var(--muted);
}
.repo .install code {
  font-family: var(--mono);
  font-weight: 500;
  font-size: 0.875rem;
  color: var(--ink);
  background: color-mix(in srgb, var(--accent) 10%, transparent);
  border: 1px solid var(--rule);
  border-radius: 3px;
  padding: 1px 6px;
  white-space: nowrap;
}
.repo--thumb { grid-template-columns: 76px minmax(0, 1fr); gap: 18px; align-items: start; }
.repo--thumb .txt { display: grid; gap: 3px; }
.repo--thumb .txt > a { font-family: var(--mono); font-weight: 500; font-size: 1rem; }
.thumb {
  width: 76px;
  height: auto;
  display: block;
  border: 1px solid var(--rule);
  border-radius: 2px;
}

.pubs { margin: 0; color: var(--muted); }

footer {
  border-top: 1px solid var(--rule);
  padding-top: 20px;
  color: var(--muted);
  font-size: 0.875rem;
}
footer p { margin: 0; }

/* research area links and subpages */
.area-more { margin-left: auto; padding-left: 12px; font-size: 0.875rem; white-space: nowrap; }
.back { font-family: var(--mono); font-size: 0.78rem; text-decoration: none; }
.back:hover { text-decoration: underline; }
.topics { display: grid; gap: clamp(40px, 6vw, 56px); }
.topic { display: grid; gap: 14px; }
.topic h3 { font-size: 1.125rem; font-weight: 600; letter-spacing: -0.005em; margin: 0; }
.topic > p { margin: 0; color: var(--muted); }
.topic .pub-list { margin: 0; padding-left: 0; }
.media {
  margin: 0;
  display: grid;
  place-items: center;
  min-height: 140px;
  border: 1px dashed var(--rule);
  border-radius: 3px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.78rem;
}
.media img, .media video { width: 100%; height: auto; display: block; border-radius: 3px; }
.media:has(img, video) { border: 0; min-height: 0; }
.repo-pair { display: grid; gap: 14px; }
@media (min-width: 640px) { .repo-pair { grid-template-columns: 1fr 1fr; } }
.pub-list.pub-list--compact { list-style: disc; padding-left: 1.2em; gap: 6px; }
.pub-list--compact li { display: list-item; }
.pub-list--compact li::marker { color: var(--muted); }
.pub-list--compact .pub-links { margin-left: 6px; }
.figure { margin: 0; display: grid; gap: 8px; }
.figure-pair { display: grid; gap: 12px; }
.figure-pair > .figure { align-content: start; min-width: 0; }
.figure-pair h4 { margin: 0 0 6px; font-family: var(--mono); font-size: 0.72rem; font-weight: 500; color: var(--muted); text-transform: uppercase; letter-spacing: 0.04em; }
@media (min-width: 480px) { .figure-pair { grid-template-columns: 1fr 1fr; } }
.figure-pair.figure-pair--3 { grid-template-columns: repeat(3, 1fr); gap: 8px; }
@media (min-width: 480px) { .figure-pair.figure-pair--square-wide { grid-template-columns: minmax(0, 9fr) minmax(0, 16fr); } }   /* a square video beside a 16:9 one, at equal height */
@media (max-width: 479px) { .figure-pair--3 h4 { font-size: 0.6rem; letter-spacing: 0; } }
.figure-row-label { margin: 4px 0 -2px; font-family: var(--mono); font-size: 0.72rem; font-weight: 500; color: var(--ink); }
.figure figcaption, .hero figcaption { font-family: var(--mono); font-size: 0.72rem; color: var(--muted); }
.credit { display: block; margin-top: 3px; letter-spacing: 0.02em; }
.credit a { color: var(--ink); font-weight: 500; text-decoration: none; }
.credit a:hover { color: var(--accent); text-decoration: underline; }