/* Peng Chen · SciML & UQ Group — site styles
   Contents: fonts · tokens · base · header · buttons · home · lists (news, publications)
             · group · teaching · software · research · footer · motion · print        */

/* ------------------------------------------------------------------ fonts */
@font-face { font-family: "Inter"; font-style: normal; font-weight: 100 900; font-display: swap;
  src: url("fonts/inter-latin-wght-normal.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }
@font-face { font-family: "Inter"; font-style: normal; font-weight: 100 900; font-display: swap;
  src: url("fonts/inter-latin-ext-wght-normal.woff2") format("woff2");
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF; }
@font-face { font-family: "Inter"; font-style: italic; font-weight: 100 900; font-display: swap;
  src: url("fonts/inter-latin-wght-italic.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }
@font-face { font-family: "Newsreader"; font-style: normal; font-weight: 400 520; font-display: swap;
  src: url("fonts/newsreader-latin-opsz-normal.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }
@font-face { font-family: "Newsreader"; font-style: normal; font-weight: 400 520; font-display: swap;
  src: url("fonts/newsreader-latin-ext-opsz-normal.woff2") format("woff2");
  unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C0, U+2113, U+2C60-2C7F, U+A720-A7FF; }
@font-face { font-family: "Newsreader"; font-style: italic; font-weight: 400 520; font-display: swap;
  src: url("fonts/newsreader-latin-opsz-italic.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }
@font-face { font-family: "JetBrains Mono"; font-style: normal; font-weight: 100 800; font-display: swap;
  src: url("fonts/jetbrains-mono-latin-wght-normal.woff2") format("woff2");
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }

/* ----------------------------------------------------------------- tokens */
:root {
  color-scheme: light;
  --paper: #fbfaf6;        /* page */
  --paper-2: #f3f1ea;      /* alternate bands */
  --card: #ffffff;
  --ink: #0c1a29;          /* text */
  --ink-2: #3a4755;        /* secondary text */
  --ink-3: #626e7b;        /* captions, labels */
  --rule: #e3dfd3;
  --rule-strong: #cdc7b6;
  --navy: #003057;         /* Georgia Tech navy */
  --gold: #b3a369;         /* Georgia Tech gold: lines and marks only */
  --gold-ink: #76652a;     /* gold dark enough for text */
  --accent: #003057;
  --accent-hover: #0b4170;
  --on-accent: #ffffff;
  --plate: #ffffff;        /* behind figures, which are drawn for white */
  --focus: #1b6fb5;
  --footer-bg: #07131f;

  --sans: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --serif: "Newsreader", "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  --gutter: clamp(20px, 5vw, 56px);
  --wrap: 1180px;
  --radius: 14px;
  --header-h: 68px;
}
:root[data-theme="dark"] {
  color-scheme: dark;
  --paper: #0a1520; --paper-2: #0e1b29; --card: #122131;
  --ink: #eef1f4; --ink-2: #bcc6d1; --ink-3: #8f9cab;
  --rule: #1f3042; --rule-strong: #2f455b;
  --navy: #a9c8e8; --gold: #c9b775; --gold-ink: #dccb8d;
  --accent: #e3d49c; --accent-hover: #f0e4b6; --on-accent: #0a1520;
  --plate: #f7f6f2; --focus: #7db9ee;
}
@media (prefers-color-scheme: dark) {      /* same values, for visitors without JavaScript */
  :root:not([data-theme]) {
    color-scheme: dark;
    --paper: #0a1520; --paper-2: #0e1b29; --card: #122131;
    --ink: #eef1f4; --ink-2: #bcc6d1; --ink-3: #8f9cab;
    --rule: #1f3042; --rule-strong: #2f455b;
    --navy: #a9c8e8; --gold: #c9b775; --gold-ink: #dccb8d;
    --accent: #e3d49c; --accent-hover: #f0e4b6; --on-accent: #0a1520;
    --plate: #f7f6f2; --focus: #7db9ee;
  }
}

/* ------------------------------------------------------------------- base */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: calc(var(--header-h) + 24px); }
body {
  margin: 0; background: var(--paper); color: var(--ink);
  font: 400 1.0625rem/1.65 var(--sans);
  font-optical-sizing: auto; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility; overflow-wrap: break-word;
}
main { display: block; min-height: 50vh; }
h1, h2, h3 { margin: 0; font-family: var(--serif); font-weight: 440; line-height: 1.12; letter-spacing: -0.016em; text-wrap: balance; }
h2 { font-size: clamp(1.8rem, 1.3rem + 1.6vw, 2.6rem); line-height: 1.08; }
h3 { font-size: 1.3rem; font-weight: 480; letter-spacing: -0.008em; }
p { margin: 0 0 1em; text-wrap: pretty; }
ul, ol { margin: 0 0 1em; padding-left: 1.2em; }
img, video, svg, canvas { max-width: 100%; }
img, video { height: auto; }
a { color: inherit; text-decoration: underline; text-decoration-color: var(--gold); text-decoration-thickness: 1.5px; text-underline-offset: 0.2em; transition: color .2s, text-decoration-color .2s; }
a:hover { color: var(--navy); text-decoration-color: currentColor; }
strong, b { font-weight: 600; }
code { font: 500 0.88em var(--mono); background: var(--paper-2); border: 1px solid var(--rule); border-radius: 6px; padding: 0.12em 0.4em; }
sub, sup { font-size: 0.72em; line-height: 0; }
::selection { background: color-mix(in srgb, var(--gold) 45%, transparent); }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 3px; border-radius: 4px; }
button { font: inherit; color: inherit; }
[hidden] { display: none !important; }

.wrap { width: min(var(--wrap), 100% - 2 * var(--gutter)); margin-inline: auto; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
.skip { position: absolute; left: 12px; top: -60px; z-index: 100; background: var(--ink); color: var(--paper); padding: 10px 16px; border-radius: 8px; text-decoration: none; transition: top .2s; }
.skip:focus { top: 12px; color: var(--paper); }
.i { width: 1em; height: 1em; flex: none; }

.label, .eyebrow {
  margin: 0 0 1em; color: var(--ink-3);
  font: 500 0.74rem/1.3 var(--mono); letter-spacing: 0.1em; text-transform: uppercase;
}
.prose p:last-child, .prose ul:last-child { margin-bottom: 0; }
.prose li { margin-bottom: 0.35em; }
.prose li::marker { color: var(--gold); }

/* ----------------------------------------------------------------- header */
.site-header {
  position: sticky; top: 0; z-index: 40;
  background: var(--paper);                                           /* for browsers without color-mix() */
  background: color-mix(in srgb, var(--paper) 84%, transparent);
  -webkit-backdrop-filter: saturate(1.5) blur(14px); backdrop-filter: saturate(1.5) blur(14px);
  border-bottom: 1px solid transparent; transition: border-color .3s;
}
.site-header.is-stuck { border-bottom-color: var(--rule); }
.progress { position: absolute; inset: auto 0 -1px; height: 2px; background: var(--gold); transform: scaleX(var(--p, 0)); transform-origin: 0 50%; opacity: 0; transition: opacity .3s; pointer-events: none; }
.has-progress .progress { opacity: 1; }
.bar { display: flex; align-items: center; gap: clamp(12px, 2vw, 28px); height: var(--header-h); }
.brand { display: flex; align-items: center; gap: 10px; margin-right: auto; color: var(--ink); text-decoration: none; }
.brand:hover { color: var(--ink); }
.brand-mark { width: 27px; height: 27px; flex: none; }
.brand-dot { fill: var(--gold); }
.brand-name { font: 500 1.3rem/1 var(--serif); letter-spacing: -0.012em; white-space: nowrap; }
.brand-tag { margin-left: 3px; padding-left: 13px; border-left: 1px solid var(--rule-strong); color: var(--ink-3); font: 500 0.68rem/1.6 var(--mono); letter-spacing: 0.09em; text-transform: uppercase; white-space: nowrap; }
.nav { display: flex; gap: clamp(14px, 2.2vw, 30px); }
.nav a { position: relative; padding: 6px 0; color: var(--ink-2); font: 500 0.92rem/1.2 var(--sans); text-decoration: none; }
.nav a::after { content: ""; position: absolute; left: 0; right: 0; bottom: -1px; height: 2px; background: var(--gold); transform: scaleX(0); transform-origin: left; transition: transform .28s cubic-bezier(.2, .7, .2, 1); }
.nav a:hover, .nav a[aria-current] { color: var(--ink); }
.nav a:hover::after, .nav a[aria-current]::after { transform: scaleX(1); }
.bar-tools { display: flex; gap: 4px; }
.icon-btn { display: inline-grid; place-items: center; width: 38px; height: 38px; padding: 0; border: 0; border-radius: 50%; background: transparent; color: var(--ink-2); cursor: pointer; transition: background .2s, color .2s; }
.icon-btn:hover { background: var(--paper-2); color: var(--ink); }
.icon-btn .i { width: 19px; height: 19px; }
.i-moon, [data-theme="dark"] .i-sun { display: none; }
[data-theme="dark"] .i-moon { display: block; }
.nav-toggle { display: none; }

@media (max-width: 900px) {
  .nav-toggle { display: inline-grid; }
  .nav { position: absolute; left: 0; right: 0; top: 100%; display: none; flex-direction: column; gap: 0; padding: 4px var(--gutter) 22px; background: var(--paper); border-bottom: 1px solid var(--rule); box-shadow: 0 24px 40px -24px rgb(0 0 0 / .25); }
  .nav-open .nav { display: flex; }
  .nav a { padding: 15px 0; border-bottom: 1px solid var(--rule); font-size: 1.12rem; }
  .nav a::after { display: none; }
  .nav a[aria-current] { color: var(--gold-ink); }
}
@media (max-width: 560px) { .brand-tag { display: none; } }

/* ---------------------------------------------------------------- buttons */
.btn {
  display: inline-flex; align-items: center; gap: 0.55em; padding: 0.86em 1.3em;
  border: 1px solid var(--rule-strong); border-radius: 999px; background: transparent; color: var(--ink);
  font: 500 0.95rem/1 var(--sans); text-decoration: none; white-space: nowrap; cursor: pointer;
  transition: background .2s, border-color .2s, color .2s;
}
.btn:hover { border-color: var(--ink); color: var(--ink); }
.btn .i { transition: transform .25s cubic-bezier(.2, .7, .2, 1); }
.btn:hover .i { transform: translateX(3px); }
.btn-primary { background: var(--accent); border-color: var(--accent); color: var(--on-accent); }
.btn-primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); color: var(--on-accent); }
.btn-small { padding: 0.62em 1em; font-size: 0.82rem; }
.actions { display: flex; flex-wrap: wrap; gap: 10px; margin: 0; }
.arrow-link { display: inline-flex; align-items: center; gap: 0.5em; padding-bottom: 3px; border-bottom: 1.5px solid var(--gold); color: var(--ink); font: 500 0.95rem/1.3 var(--sans); text-decoration: none; }
.arrow-link .i { transition: transform .25s cubic-bezier(.2, .7, .2, 1); }
.arrow-link:hover { border-bottom-color: currentColor; }
.arrow-link:hover .i { transform: translateX(4px); }
.more { margin: clamp(24px, 3vw, 36px) 0 0; }

/* --------------------------------------------------------------- sections */
.section { padding-block: clamp(64px, 9vw, 128px); }
.section-tight { padding-block: clamp(28px, 4vw, 52px); }
.section-alt { background: var(--paper-2); border-block: 1px solid var(--rule); }
.section-head { margin-bottom: clamp(22px, 3vw, 38px); }
.section-head .label:last-child { margin-bottom: 0; }

.page-head { position: relative; overflow: hidden; padding: clamp(48px, 7vw, 104px) 0 clamp(4px, 1.5vw, 20px); }
.page-head .wrap { position: relative; z-index: 1; }
/* The page-head figure: a still of the home page's ensemble, drawn by build.py (motif) */
.head-motif { position: absolute; right: 0; top: 50%; width: min(58%, 800px); aspect-ratio: 760 / 230; transform: translateY(-40%); pointer-events: none;
  -webkit-mask-image: linear-gradient(to right, transparent, #000 40%, #000 90%, transparent); mask-image: linear-gradient(to right, transparent, #000 40%, #000 90%, transparent); }
.motif { display: block; width: 100%; height: 100%; }
.m-band { fill: var(--gold); opacity: .15; }
.m-s { fill: none; stroke: var(--ink-3); stroke-width: 1; opacity: .5; }
.m-m { fill: none; stroke: var(--gold-ink); stroke-width: 1.8; }
.m-t { stroke: var(--rule-strong); stroke-width: 1; }
.m-d { fill: var(--ink); stroke: var(--paper); stroke-width: 2; }
@media (max-width: 760px) {
  .page-head { padding-bottom: 76px; }
  .head-motif { top: auto; bottom: 0; width: 100%; height: 64px; aspect-ratio: auto; transform: none; opacity: .85;
    -webkit-mask-image: linear-gradient(to right, transparent, #000 18%, #000 82%, transparent); mask-image: linear-gradient(to right, transparent, #000 18%, #000 82%, transparent); }
}
.page-title { font: 400 clamp(2.5rem, 1.6rem + 3.6vw, 4.2rem)/1.03 var(--serif); letter-spacing: -0.026em; }
.page-intro { max-width: 58ch; margin: 1em 0 0; color: var(--ink-2); font-size: clamp(1.05rem, 1rem + 0.35vw, 1.22rem); line-height: 1.55; }

.plate { overflow: hidden; padding: 10px; border: 1px solid var(--rule); border-radius: 12px; background: var(--plate); }
.plate img, .plate video { display: block; width: 100%; border-radius: 4px; }
.plate.narrow { max-width: 460px; margin-inline: auto; }
figure { margin: 0; }
figcaption { margin-top: 10px; color: var(--ink-3); font-size: 0.84rem; line-height: 1.5; text-wrap: pretty; }
.zoom { cursor: zoom-in; }
.only-dark { display: none !important; }
[data-theme="dark"] .only-dark { display: block !important; }
[data-theme="dark"] .only-light { display: none !important; }
.plate-themed { background: var(--ground, var(--plate)); }
[data-theme="dark"] .plate-themed { background: #091117; }

/* ------------------------------------------------------------------- hero */
.hero { padding-top: clamp(36px, 5.2vw, 76px); }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1fr) clamp(220px, 23vw, 290px); gap: clamp(32px, 7vw, 110px); align-items: end; }
.display { margin: 0.3em 0 0.48em; font: 400 clamp(2.5rem, 1.1rem + 4.4vw, 4.5rem)/1.03 var(--serif); letter-spacing: -0.03em; text-wrap: wrap; }
.display em { color: var(--gold-ink); font-style: italic; font-weight: 400; letter-spacing: -0.02em; }
.lead { max-width: 56ch; margin-bottom: 1.6em; color: var(--ink-2); font-size: clamp(1.08rem, 1rem + 0.45vw, 1.28rem); line-height: 1.55; }
.hero-pi .portrait { display: block; width: 100%; aspect-ratio: 4 / 5; object-fit: cover; object-position: 50% 20%; border-radius: var(--radius); background: var(--paper-2); }
.pi-meta { margin-top: 16px; }
.pi-name { margin: 0; font: 480 1.4rem/1.2 var(--serif); letter-spacing: -0.01em; }
.pi-role { margin: 0.3em 0 0; color: var(--ink-3); font-size: 0.86rem; line-height: 1.45; }
.pub-links a { padding-bottom: 1px; border-bottom: 1px solid var(--gold); color: var(--ink-2); text-decoration: none; }
.pub-links a:hover { border-bottom-color: currentColor; color: var(--ink); }
.cite { display: none; padding: 0 0 1px; border: 0; border-bottom: 1px solid var(--gold); border-radius: 0; background: none; color: var(--ink-2); font: inherit; letter-spacing: inherit; text-transform: inherit; cursor: pointer; }
.js .cite { display: inline; }
.cite:hover { border-bottom-color: currentColor; color: var(--ink); }
.cite.is-done { border-bottom-color: transparent; color: var(--gold-ink); }
.icon-links { display: flex; flex-wrap: wrap; gap: 6px; margin: 0.8em 0 0; }
.icon-links a { display: inline-grid; place-items: center; width: 34px; height: 34px; border: 1px solid var(--rule-strong); border-radius: 50%; color: var(--ink-2); transition: border-color .2s, color .2s, background .2s; }
.icon-links a:hover { border-color: var(--ink); background: var(--card); color: var(--ink); }
.icon-links .i { width: 17px; height: 17px; }

.ensemble { display: none; margin-top: clamp(32px, 4.6vw, 60px); }      /* drawn by assets/hero.js */
.js .ensemble { display: block; }
html:not(.js) .hero { padding-bottom: clamp(24px, 4vw, 48px); border-bottom: 1px solid var(--rule); }
.ensemble-stage { position: relative; height: clamp(230px, 27vw, 390px); border-block: 1px solid var(--rule); background: linear-gradient(to bottom, transparent 20%, var(--paper-2)); background: linear-gradient(to bottom, transparent 20%, color-mix(in srgb, var(--paper-2) 80%, transparent)); cursor: crosshair; touch-action: pan-y; }
.ensemble canvas { position: absolute; inset: 0; display: block; width: 100%; height: 100%; }
.ensemble-cap { display: flex; flex-wrap: wrap; align-items: flex-start; justify-content: space-between; gap: 14px 32px; margin-top: 16px; }
.cap-text { flex: 1 1 380px; max-width: 64ch; margin: 0; color: var(--ink-3); font-size: 0.88rem; line-height: 1.55; }
.cap-tools { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 10px; }
.stats { display: flex; gap: 18px; margin: 0 8px 0 0; color: var(--ink-3); font: 500 0.76rem/1.3 var(--mono); white-space: nowrap; }
.stats b { color: var(--ink); font-weight: 600; font-variant-numeric: tabular-nums; }

@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; gap: 32px; }
  .hero-pi { display: grid; grid-template-columns: 76px 1fr; gap: 16px; align-items: center; padding-top: 22px; border-top: 1px solid var(--rule); }
  .hero-pi .portrait { aspect-ratio: 1; border-radius: 50%; }
  .pi-meta { margin: 0; }
  .pi-name { font-size: 1.2rem; }
}

/* ------------------------------------------------------- home: feature */
.feature { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 6fr); gap: clamp(32px, 6vw, 92px); align-items: center; }
.feature-lead { max-width: 52ch; margin: 1.1em 0 0; color: var(--ink-2); }
.feature-items { margin: 28px 0 0; padding: 0; list-style: none; }
.feature-items li { display: grid; grid-template-columns: 112px minmax(0, 1fr); column-gap: 20px; padding: 16px 0; border-top: 1px solid var(--rule-strong); }
.feature-items h3 { grid-row: span 2; font: 600 0.84rem/1.7 var(--mono); letter-spacing: 0.02em; }
.feature-items p { margin: 0; font-size: 0.95rem; line-height: 1.55; }
.feature-items .pub-links { margin-top: 0.55em; }
@media (max-width: 900px) { .feature { grid-template-columns: 1fr; } .feature-media { max-width: 520px; } }
@media (max-width: 480px) { .feature-items li { grid-template-columns: 1fr; } .feature-items h3 { grid-row: auto; } }

/* ------------------------------------------------- home: sizes and cards */
.page-home .section-head h2, .page-home .join-copy h2, .page-home .feature-copy h2 { font-size: clamp(2rem, 1.35rem + 2.3vw, 3.1rem); line-height: 1.05; }
.page-home .section-head { margin-bottom: clamp(26px, 3.6vw, 46px); }
/* the live figure in navy and gold */
.page-home .ensemble { --ink: #003a6b; --ink-3: #4f6379; --gold: #2f73b8; --gold-ink: #b98a12; --accent: #003057; }
[data-theme="dark"] .page-home .ensemble { --ink: #b7d3ee; --ink-3: #8fa3b8; --gold: #3f83c8; --gold-ink: #ecc55a; --accent: #ecc55a; }
.page-home .ensemble-cap .cap-text { color: var(--ink-3); }

.theme-cards { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: clamp(30px, 3.6vw, 44px) clamp(16px, 2.4vw, 30px); margin: 0; padding: 0; list-style: none; }
.theme-card { position: relative; }
.theme-card-img { overflow: hidden; aspect-ratio: 4 / 3; border-radius: 12px; background: var(--paper-2); }
.theme-card-img img { display: block; width: 100%; height: 100%; object-fit: cover; transition: transform .8s cubic-bezier(.2, .7, .2, 1); }
.theme-card:hover .theme-card-img img { transform: scale(1.05); }
.theme-card .label { margin: 1.15em 0 0; color: var(--gold-ink); }
.theme-card h3 { margin: 0.4em 0 0.35em; font-size: 1.32rem; line-height: 1.2; }
.section-intro { max-width: 44em; margin: 0.9em 0 0; color: var(--ink-2); font-size: clamp(1.04rem, 1rem + 0.3vw, 1.2rem); line-height: 1.55; }
.theme-card h3 a { color: inherit; text-decoration: none; background: linear-gradient(var(--gold), var(--gold)) 0 100% / 0 1.5px no-repeat; transition: background-size .35s cubic-bezier(.2, .7, .2, 1); }
.theme-card h3 a::after { content: ""; position: absolute; inset: 0; }
.theme-card:hover h3 a, .theme-card h3 a:focus-visible { background-size: 100% 1.5px; }
.theme-card p { margin: 0; color: var(--ink-2); font-size: 0.95rem; line-height: 1.5; }
.theme-cards .reveal:nth-child(2) { transition-delay: .07s; }
.theme-cards .reveal:nth-child(3) { transition-delay: .14s; }
.theme-cards .reveal:nth-child(4) { transition-delay: .21s; }
@media (min-width: 901px) { .theme-card h3 { min-height: 2.4em; } }
@media (max-width: 900px) { .theme-cards { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (max-width: 540px) { .theme-card h3 { font-size: 1.12rem; } .theme-card p { font-size: 0.88rem; } }
@media (max-width: 330px) { .theme-cards { grid-template-columns: 1fr; } }

/* one band in Georgia Tech navy */
.band-navy { --focus: #9fcbf2; background: var(--navy); color: #d6e1ec; }
[data-theme="dark"] .band-navy { background: #0e2c49; }
.band-navy h2, .band-navy h3 { color: #fff; }
.band-navy .label { color: #dccd96; }
.band-navy .feature-lead, .band-navy .feature-items p { color: #c9d6e3; }
.band-navy .feature-items li { border-top-color: rgb(255 255 255 / .22); }
.band-navy figcaption { color: #a9bdd1; }
.band-navy .plate { border-color: transparent; }
.band-navy .pub-links a { border-bottom-color: #dccd96; color: #fff; }
.band-navy .pub-links a:hover { border-bottom-color: #fff; color: #fff; }
.band-navy ::selection { background: rgb(220 205 150 / .4); }
/* the page ends with the group band, which runs into the footer photograph */
.page-home #join { border-bottom: 0; }
.page-home .site-footer { margin-top: 0; background: var(--paper-2); }

/* ----------------------------------------------- lists: news, publications */
.two-col { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 56px clamp(40px, 7vw, 108px); }
@media (max-width: 860px) { .two-col { grid-template-columns: 1fr; } }

.news, .pubs { margin: 0; padding: 0; list-style: none; }
.news-item, .pub { padding: 17px 0; border-top: 1px solid var(--rule); }
.news > :last-child, .pubs > :last-child { border-bottom: 1px solid var(--rule); }
.news-date { margin: 0 0 0.4em; color: var(--ink-3); font: 500 0.72rem/1.4 var(--mono); letter-spacing: 0.07em; text-transform: uppercase; }
.news-text { margin: 0; font-size: 0.96rem; line-height: 1.58; }
.news-wide .news-item { display: grid; grid-template-columns: 200px minmax(0, 1fr); gap: 4px 24px; align-items: baseline; }
.news-wide .news-date { margin: 0; }
.news-wide .news-text { font-size: 1rem; }
/* a rail with one dot per item, between the dates and the text */
@media (min-width: 721px) {
  .news-wide { position: relative; }
  .news-wide::before { content: ""; position: absolute; left: 211px; top: 0; bottom: 0; width: 1px; background: var(--rule); }
  .news-wide .news-item { position: relative; }
  .news-wide .news-item::after { content: ""; position: absolute; left: 207px; top: 25px; width: 9px; height: 9px; border: 1.5px solid var(--rule-strong); border-radius: 50%; background: var(--paper); transition: background .2s, border-color .2s, transform .25s cubic-bezier(.2, .7, .2, 1); }
  .news-wide .news-item:hover::after { border-color: var(--gold-ink); background: var(--gold); transform: scale(1.3); }
}
/* a gold bar beside the row under the pointer */
@media (hover: hover) {
  .year-group .pub { position: relative; }
  .year-group .pub::before { content: ""; position: absolute; left: -14px; top: 18px; bottom: 18px; width: 2px; background: var(--gold); transform: scaleY(0); transform-origin: 50% 0; transition: transform .3s cubic-bezier(.2, .7, .2, 1); }
  .year-group .pub:hover::before { transform: scaleY(1); }
}
.filter-status button { margin-left: 0.6em; padding: 0; border: 0; border-bottom: 1px solid var(--gold); background: none; color: var(--ink-2); font: inherit; cursor: pointer; }
.filter-status button:hover { color: var(--ink); border-bottom-color: currentColor; }
@media (max-width: 720px) { .news-wide .news-item { grid-template-columns: 1fr; } }

.pub-title { margin: 0 0 0.32em; font: 480 1.2rem/1.3 var(--serif); letter-spacing: -0.006em; text-wrap: pretty; }
.pub-title a, a.pub-title { color: var(--ink); text-decoration: none; background: linear-gradient(var(--gold), var(--gold)) 0 100% / 0 1.5px no-repeat; transition: background-size .3s cubic-bezier(.2, .7, .2, 1), color .2s; }
.pub-title a:hover, a.pub-title:hover { color: var(--ink); background-size: 100% 1.5px; }
.pubs-compact .pub-title { display: inline; font-size: 1.12rem; }
.pub-authors { margin: 0; color: var(--ink-2); font-size: 0.93rem; line-height: 1.5; }
.pub-venue { margin: 0.15em 0 0; color: var(--ink-3); font-size: 0.93rem; line-height: 1.5; }
.pub-venue em, .pub-meta em { color: var(--ink-2); font-family: var(--serif); font-size: 1.07em; }
.pub-meta { margin: 0.3em 0 0; color: var(--ink-3); font-size: 0.86rem; line-height: 1.5; }
.pub-links { display: flex; flex-wrap: wrap; align-items: center; gap: 6px 14px; margin: 0.7em 0 0; font: 500 0.72rem/1.4 var(--mono); letter-spacing: 0.06em; text-transform: uppercase; }
.tag { padding: 0.22em 0.62em; border: 1px solid var(--rule); border-radius: 5px; background: var(--paper-2); color: var(--ink-3); letter-spacing: 0.05em; }
.tag-preprint { border-style: dashed; background: transparent; }

.year-group { display: grid; grid-template-columns: 124px minmax(0, 1fr); gap: 8px 24px; padding-top: clamp(20px, 3vw, 36px); }
.year { position: sticky; top: calc(var(--header-h) + 22px); align-self: start; margin-top: 12px; color: var(--ink-3); font: 400 2.1rem/1 var(--serif); letter-spacing: -0.02em; font-variant-numeric: lining-nums tabular-nums; }
@media (max-width: 720px) { .year-group { grid-template-columns: 1fr; } .year { position: static; margin: 0 0 4px; } }

.toolbar { display: flex; flex-wrap: wrap; align-items: center; gap: 14px 24px; }
.search { position: relative; flex: 1 1 300px; max-width: 440px; }
.search .i { position: absolute; left: 1em; top: 50%; width: 17px; height: 17px; transform: translateY(-50%); color: var(--ink-3); pointer-events: none; }
.search input { width: 100%; padding: 0.66em 1em 0.66em 2.7em; border: 1px solid var(--rule-strong); border-radius: 999px; background: var(--card); color: var(--ink); font: 400 0.95rem/1.4 var(--sans); }
.search input::placeholder { color: var(--ink-3); opacity: 1; }
.search input:focus { border-color: var(--ink); outline: none; }
.chips, .jump { display: flex; flex-wrap: wrap; gap: 8px; }
.chip { padding: 0.46em 0.95em; border: 1px solid var(--rule-strong); border-radius: 999px; background: transparent; color: var(--ink-2); font: 500 0.84rem/1.3 var(--sans); cursor: pointer; transition: background .2s, color .2s, border-color .2s; }
.chip span { margin-left: 0.3em; color: var(--ink-3); font: 500 0.7rem var(--mono); }
.chip:hover { border-color: var(--ink); }
.chip[aria-pressed="true"] { border-color: var(--ink); background: var(--ink); color: var(--paper); }
.chip[aria-pressed="true"] span { color: inherit; opacity: 0.7; }
.jump a { padding: 0.4em 0.9em; border: 1px solid var(--rule-strong); border-radius: 999px; color: var(--ink-2); font: 500 0.78rem/1.3 var(--mono); text-decoration: none; }
.jump a:hover { border-color: var(--ink); color: var(--ink); }
.jump-left { margin-bottom: clamp(8px, 2vw, 24px); }
.filter-status { min-height: 1.5em; margin: 14px 0 0; color: var(--ink-3); font: 500 0.76rem/1.5 var(--mono); }
.filter-empty { margin: 32px 0; color: var(--ink-3); }

/* ---------------------------------------------------------- home: join */
.join { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); gap: clamp(32px, 6vw, 88px); align-items: center; }
.join-copy p { color: var(--ink-2); }
.join-copy h2 { margin-bottom: 0.6em; }
.join-copy .actions { margin-top: 1.8em; }
.group-photo img { display: block; width: 100%; border-radius: var(--radius); }
.group-photo-wide figcaption { max-width: 78ch; }
@media (max-width: 900px) { .join { grid-template-columns: 1fr; } }

/* ------------------------------------------------------------------ group */
.pi-card { display: grid; grid-template-columns: clamp(170px, 22vw, 260px) minmax(0, 1fr); gap: clamp(24px, 5vw, 64px); align-items: start; }
.pi-card .portrait { display: block; width: 100%; aspect-ratio: 4 / 5; object-fit: cover; object-position: 50% 20%; border-radius: var(--radius); }
.pi-card h2 { margin-bottom: 0.2em; }
.pi-card .pi-role { margin-bottom: 1.4em; font-size: 0.95rem; }
.pi-card p { max-width: 68ch; color: var(--ink-2); }
.pi-card .icon-links { margin-top: 1.2em; }
.pi-office { margin: 0.9em 0 0; color: var(--ink-3); font-size: 0.88rem; }
@media (max-width: 640px) { .pi-card { grid-template-columns: 1fr; } .pi-card .portrait { max-width: 220px; } }

.people { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: clamp(28px, 4vw, 48px) clamp(16px, 2.6vw, 34px); margin: 0; padding: 0; list-style: none; }
.person-photo { display: block; overflow: hidden; aspect-ratio: 4 / 5; border-radius: 12px; background: var(--paper-2); }
.person-photo img { display: block; width: 100%; height: 100%; object-fit: cover; object-position: 50% 25%; transition: transform .7s cubic-bezier(.2, .7, .2, 1); }
.person:hover .person-photo img { transform: scale(1.035); }
.person h3 { margin: 0.85em 0 0.18em; font-size: 1.22rem; line-height: 1.22; }
.person-role, .person-note { margin: 0; color: var(--ink-3); font-size: 0.88rem; line-height: 1.45; }
.person-initials { position: relative; display: grid; place-items: center; border: 1px solid var(--rule); color: var(--ink-2); font: 400 clamp(2rem, 4.2vw, 3.1rem)/1 var(--serif); letter-spacing: 0.04em; }
.person-initials .motif { position: absolute; inset: 0; opacity: .8; }
.person-initials .m-t { display: none; }
.person-initials span { position: relative; padding: 0.18em 0.3em; border-radius: 8px; background: color-mix(in srgb, var(--paper-2) 78%, transparent); }
.person-papers { margin: 0.75em 0 0; }
.person-papers .arrow-link { font-size: 0.82rem; }
.join-strip { display: flex; align-items: center; gap: 16px; margin-top: clamp(28px, 4vw, 48px); padding: 18px 24px; border: 1.5px dashed var(--rule-strong); border-radius: 12px; color: var(--ink-2); text-decoration: none; transition: border-color .2s, color .2s, background .2s; }
.join-strip:hover { border-color: var(--gold-ink); background: var(--card); color: var(--ink); }
.join-strip strong { margin-right: 0.5em; color: var(--ink); font: 480 1.15rem/1.3 var(--serif); }
.join-strip .i { margin-left: auto; transition: transform .25s cubic-bezier(.2, .7, .2, 1); }
.join-strip:hover .i { transform: translateX(4px); }
.join-plus { color: var(--gold-ink); font: 400 2rem/0.8 var(--serif); }
@media (max-width: 980px) { .people { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
@media (max-width: 620px) { .people { grid-template-columns: repeat(2, minmax(0, 1fr)); } }

.alumni { columns: 2; column-gap: clamp(32px, 6vw, 80px); margin: 0; padding: 0; list-style: none; }
.alumni li { display: grid; gap: 2px; padding: 13px 0; border-top: 1px solid var(--rule); break-inside: avoid; }
.alum-name { font: 480 1.1rem/1.3 var(--serif); }
.alum-detail { color: var(--ink-3); font-size: 0.88rem; line-height: 1.45; }
.alum-now { display: block; color: var(--ink-2); }
@media (max-width: 720px) { .alumni { columns: 1; } }

/* --------------------------------------------------------------- teaching */
.now-teaching { padding: clamp(24px, 4vw, 44px); border: 1px solid var(--rule); border-left: 3px solid var(--gold); border-radius: var(--radius); background: var(--card); }
.now-teaching h2 { margin-bottom: 0.15em; }
.course-code { margin: 0; color: var(--ink-3); font: 500 0.82rem/1.5 var(--mono); letter-spacing: 0.04em; }
.pulse { display: inline-block; width: 8px; height: 8px; margin-right: 0.8em; border-radius: 50%; background: var(--gold-ink); box-shadow: 0 0 0 0 color-mix(in srgb, var(--gold) 70%, transparent); animation: pulse 2.4s ease-out infinite; }
@keyframes pulse { to { box-shadow: 0 0 0 10px transparent; } }
.facts { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px 32px; margin: 28px 0 0; padding-top: 22px; border-top: 1px solid var(--rule); }
.facts dt { margin-bottom: 0.3em; color: var(--ink-3); font: 500 0.72rem/1.4 var(--mono); letter-spacing: 0.1em; text-transform: uppercase; }
.facts dd { margin: 0; font-size: 0.98rem; line-height: 1.45; }
@media (max-width: 720px) { .facts { grid-template-columns: 1fr; } }
.course { display: grid; grid-template-columns: minmax(0, 4fr) minmax(0, 7fr); gap: 20px clamp(32px, 6vw, 88px); padding: clamp(32px, 5vw, 60px) 0; border-top: 1px solid var(--rule); }
.course:first-child { border-top: 0; padding-top: 0; }
.course h2 { margin: 0.25em 0 0; font-size: clamp(1.6rem, 1.3rem + 1vw, 2.1rem); }
.course .prose { color: var(--ink-2); }
.terms { display: flex; flex-wrap: wrap; gap: 6px; margin: 20px 0 0; padding: 0; list-style: none; }
.terms li { padding: 0.25em 0.7em; border: 1px solid var(--rule-strong); border-radius: 999px; color: var(--ink-3); font: 500 0.72rem/1.4 var(--mono); }
.terms li:first-child { border-color: var(--ink); color: var(--ink); }
.course-body { min-width: 0; }
.steps { display: flex; flex-wrap: wrap; gap: 6px 0; margin: 1.7em 0 0; padding: 0; list-style: none; }
.steps li { display: inline-flex; align-items: center; color: var(--ink-2); font: 500 0.76rem/1.5 var(--mono); }
.steps li:not(:last-child)::after { content: "\2192"; margin: 0 0.7em; color: var(--gold-ink); }
.outline, .course-facts { grid-column: 1 / -1; }
.outline { margin-top: clamp(8px, 1.6vw, 20px); padding-top: clamp(22px, 3vw, 34px); border-top: 1px solid var(--rule); }
.outline .label { margin-bottom: 0.5em; }
.outline-note { margin: 0; color: var(--ink-3); font-size: 0.9rem; }
.outline-list { columns: 2; column-gap: clamp(32px, 6vw, 88px); margin: 1.3em 0 0; padding: 0; list-style: none; counter-reset: wk; }
.outline-list li { position: relative; padding: 14px 0 15px 46px; border-top: 1px solid var(--rule); break-inside: avoid; counter-increment: wk; }
.outline-list li::before { content: counter(wk, decimal-leading-zero); position: absolute; left: 0; top: 19px; color: var(--gold-ink); font: 500 0.74rem var(--mono); letter-spacing: 0.1em; }
.outline-list h4 { margin: 0; font: 480 1.08rem/1.3 var(--serif); letter-spacing: -0.006em; text-wrap: pretty; }
.outline-list p { margin: 0.4em 0 0; color: var(--ink-3); font-size: 0.86rem; line-height: 1.52; }
.course-facts { margin-top: 0; }
.reading { grid-column: 1 / -1; border-top: 1px solid var(--rule); }
.reading summary { display: flex; align-items: baseline; gap: 0.7em; padding: 16px 0; cursor: pointer; font: 480 1.12rem/1.3 var(--serif); list-style: none; }
.reading summary::-webkit-details-marker { display: none; }
.reading summary::before { content: "+"; width: 0.9em; color: var(--gold-ink); font: 400 1.35rem/1 var(--serif); transition: transform .25s cubic-bezier(.2, .7, .2, 1); }
.reading[open] summary::before { transform: rotate(45deg); }
.reading summary span { color: var(--ink-3); font: 500 0.72rem var(--mono); letter-spacing: 0.08em; text-transform: uppercase; }
.reading-groups { columns: 2; column-gap: clamp(32px, 6vw, 88px); padding: 6px 0 22px; }
.reading-groups section { break-inside: avoid; margin-bottom: 1.5em; }
.reading-groups h4 { margin: 0 0 0.45em; font: 600 0.9rem/1.4 var(--sans); }
.reading-groups ul { margin: 0; padding: 0; list-style: none; }
.reading-groups li { padding: 0.3em 0; color: var(--ink-3); font-size: 0.86rem; line-height: 1.5; }
.reading-groups a { color: var(--ink); text-decoration-thickness: 1px; }
@media (max-width: 820px) { .reading-groups { columns: 1; } }
@media (max-width: 820px) { .course { grid-template-columns: 1fr; } .outline-list { columns: 1; } }

/* --------------------------------------------------------------- software */
.lib { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 6fr); gap: 28px clamp(32px, 6vw, 84px); align-items: start; padding: clamp(36px, 6vw, 72px) 0; border-top: 1px solid var(--rule); }
.lib:first-child { border-top: 0; padding-top: clamp(12px, 2vw, 24px); }
.lib h2 { font: 500 clamp(1.5rem, 1.25rem + 0.9vw, 1.95rem)/1.1 var(--mono); letter-spacing: -0.03em; }
.lib-tagline { margin: 0.6em 0 1.1em; font: 420 1.28rem/1.3 var(--serif); letter-spacing: -0.008em; text-wrap: balance; }
.lib .prose { color: var(--ink-2); font-size: 0.98rem; }
.install { margin: 1.3em 0 0; }
.install code { display: inline-block; padding: 0.55em 0.9em; border-radius: 8px; font-size: 0.84rem; }
.install code::before { content: "$ "; color: var(--ink-3); }
.lib-links { display: flex; flex-wrap: wrap; gap: 8px; margin: 1.4em 0 0; }
.lib-plates { display: grid; gap: 12px; align-items: start; }
.lib-media-2 .lib-plates { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.lib-media-3 .lib-plates { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.lib-media-4 .lib-plates { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.lib-media-3 .plate, .lib-media-4 .plate { padding: 6px; }
@media (max-width: 900px) { .lib { grid-template-columns: 1fr; } }
@media (max-width: 520px) { .lib-media-4 .lib-plates { grid-template-columns: repeat(2, minmax(0, 1fr)); } }

/* --------------------------------------------------------------- research */
.lead-wide { max-width: 46em; margin: 0; color: var(--ink-2); font-size: clamp(1.08rem, 1rem + 0.4vw, 1.24rem); line-height: 1.62; }
.lead-wide strong { color: var(--ink); font-weight: 600; }
.concept { max-width: 900px; margin: clamp(36px, 5vw, 64px) auto 0; }
.concept figcaption { text-align: center; }
.concept-svg { display: block; width: 100%; height: auto; }
.c-node { fill: var(--card); stroke: var(--ink); stroke-width: 1.4; }
.c-node-u { fill: var(--card); fill: color-mix(in srgb, var(--gold) 20%, var(--card)); stroke: var(--gold-ink); stroke-dasharray: 5 4; }
.c-name { fill: var(--ink); font: 480 21px var(--serif); letter-spacing: -0.01em; }
.c-label { fill: var(--ink-3); font: 500 12.5px var(--mono); }
.c-edge, .c-time { fill: none; stroke: var(--ink-3); stroke-width: 1.3; }
.c-time { stroke-dasharray: 2 6; stroke-linecap: round; }
.c-head { fill: var(--ink-3); }
.areas { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 32px clamp(24px, 4vw, 56px); margin-top: clamp(40px, 5vw, 68px); }
.areas > div { padding-top: 18px; border-top: 1px solid var(--ink); }
.areas h3 { margin-bottom: 0.8em; font-size: 1.22rem; font-weight: 480; line-height: 1.25; letter-spacing: -0.008em; }
.areas ul { margin: 0; padding: 0; list-style: none; }
.areas li { padding: 0.5em 0; border-top: 1px solid var(--rule); color: var(--ink-2); font-size: 0.93rem; line-height: 1.45; }
@media (max-width: 820px) { .areas { grid-template-columns: 1fr; } }

.challenges { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 clamp(32px, 5vw, 72px); margin: clamp(24px, 3vw, 40px) 0; padding: 0; list-style: none; counter-reset: q; }
.challenges li { position: relative; padding: 16px 0 16px 46px; border-top: 1px solid var(--rule-strong); color: var(--ink-2); font-size: 0.97rem; line-height: 1.55; counter-increment: q; }
.challenges li::before { content: counter(q, decimal-leading-zero); position: absolute; left: 0; top: 19px; color: var(--gold-ink); font: 500 0.74rem var(--mono); letter-spacing: 0.1em; }
.approach { font-size: 1.02rem; }
.support { max-width: 62em; margin: clamp(26px, 3.4vw, 40px) 0 0; padding-top: 18px; border-top: 1px solid var(--rule-strong); color: var(--ink-2); font-size: 0.92rem; line-height: 1.6; }
.support .label { display: inline; margin: 0 1.3em 0 0; }
/* sponsors: logos in their own colours on tiles that stay light in the dark theme */
.support-logos { max-width: none; }
.support-logos .label { display: block; margin: 0 0 16px; }
.sponsors { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: 12px; margin: 0; padding: 0; list-style: none; }
.sponsor { display: flex; align-items: center; justify-content: center; gap: 12px; height: 104px; padding: 16px 18px; border: 1px solid var(--rule); border-radius: 12px; background: var(--plate); text-decoration: none; transition: border-color .25s; }
.sponsor:hover, .sponsor:focus-visible { border-color: var(--gold); }
.sponsor img { width: calc(var(--logo, 70px) * var(--r, 1)); }
.sponsor-mark img { flex: none; width: 46px; }
.sponsor-name { color: #17222e; font: 500 1.3rem/1.1 var(--serif); letter-spacing: -0.01em; }
.support-note { max-width: 62em; margin: 16px 0 0; }
@media (max-width: 960px) { .sponsors { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
@media (max-width: 520px) { .sponsors { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; } .sponsor { height: 92px; padding: 14px; --logo: 62px; } }
@media (max-width: 820px) { .challenges { grid-template-columns: 1fr; } }

.with-toc { display: grid; grid-template-columns: 210px minmax(0, 1fr); gap: clamp(32px, 5vw, 72px); align-items: start; }
.toc { position: sticky; top: calc(var(--header-h) + 28px); max-height: calc(100vh - var(--header-h) - 56px); overflow: auto; }
.toc .label { margin: 0 0 0.7em; }
.toc ul { margin: 0 0 2em; padding: 0; list-style: none; border-left: 1px solid var(--rule); }
.toc a { display: block; margin-left: -1px; padding: 0.38em 0 0.38em 14px; border-left: 2px solid transparent; color: var(--ink-3); font-size: 0.86rem; line-height: 1.35; text-decoration: none; transition: color .2s, border-color .2s; }
.toc a:hover { color: var(--ink); }
.toc a.is-active { border-left-color: var(--gold-ink); color: var(--ink); }
@media (max-width: 980px) { .with-toc { grid-template-columns: 1fr; } .toc { display: none; } }

.topics-title { padding-bottom: 0.5em; border-bottom: 1px solid var(--ink); }
.topics-title:not(:first-child) { margin-top: clamp(56px, 8vw, 112px); }
.topic { padding: clamp(36px, 5.5vw, 68px) 0; border-bottom: 1px solid var(--rule); }
.topic:last-of-type { border-bottom: 0; }
.topic h3 { max-width: 24em; font-size: clamp(1.55rem, 1.25rem + 1.1vw, 2.15rem); line-height: 1.12; letter-spacing: -0.018em; text-wrap: balance; }
.topic-lead { max-width: 33em; margin: 0.75em 0 0; color: var(--ink); font: 420 clamp(1.1rem, 1.02rem + 0.4vw, 1.3rem)/1.42 var(--serif); letter-spacing: -0.006em; text-wrap: pretty; }
.topic .prose { max-width: 46em; margin-top: 1.3em; color: var(--ink-2); }
.topic .prose strong { color: var(--ink); font-weight: 600; }
.topic-papers { margin-top: clamp(26px, 3.2vw, 40px); }
.topic-papers .label { margin-bottom: 0.9em; }
.topic-papers .refs { margin-top: 0; }
.topic-links { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin: 1.5em 0 0; }
.topic-links .label { margin: 0 0.6em 0 0; }
.refs { max-width: 50em; margin: 1.4em 0 0; padding: 0; list-style: none; }
.refs li { padding: 0.6em 0 0.6em 16px; border-left: 2px solid var(--gold); color: var(--ink-3); font-size: 0.88rem; line-height: 1.5; }
.refs li + li { margin-top: 6px; }
.refs a { color: var(--ink); text-decoration-thickness: 1px; }
.refs em { font-family: var(--serif); font-size: 1.07em; color: var(--ink-2); }
.figs { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: 24px 20px; align-items: start; margin-top: clamp(24px, 3vw, 36px); }
.fig-full { grid-column: span 6; }
.fig-twothirds { grid-column: span 4; }
.fig-half { grid-column: span 3; }
.fig-third { grid-column: span 2; }
.fig .row, .fig .stack { display: grid; gap: 8px; align-items: center; }
.fig .row-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.fig .row-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
@media (min-width: 761px) { .fig-rows-2 { grid-row: span 2; } .fig-rows-3 { grid-row: span 3; } .fig-rows-4 { grid-row: span 4; } }
@media (max-width: 760px) { .fig-twothirds, .fig-half, .fig-third { grid-column: span 6; } }
@media (max-width: 760px) { .fig-slim .plate { max-width: 250px; margin-inline: auto; } }
/* on a phone the parts of a wide figure are stacked, and its caption says top and bottom */
.when-stacked { display: none; }
@media (max-width: 560px) {
  .fig .row-wide { grid-template-columns: minmax(0, 1fr); }
  .when-wide { display: none; }
  .when-stacked { display: inline; }
}
/* a figure narrower than the row, alone in it, with its caption beside it */
@media (min-width: 761px) {
  .fig-side { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); column-gap: 20px; align-items: start; }
  .fig-side > figcaption { margin-top: 0; padding-top: 11px; border-top: 1px solid var(--rule-strong); }
  .side-twothirds > .plate { grid-column: span 4; } .side-twothirds > figcaption { grid-column: span 2; }
  .side-half > .plate, .side-half > figcaption { grid-column: span 3; }
  .side-third > .plate { grid-column: span 2; } .side-third > figcaption { grid-column: span 4; max-width: 44em; }
}

.brief { display: grid; grid-template-columns: 220px minmax(0, 1fr); gap: 16px clamp(20px, 3.4vw, 40px); align-items: start; padding: clamp(24px, 3.2vw, 36px) 0; border-bottom: 1px solid var(--rule); }
.brief:last-child { border-bottom: 0; }
.brief-thumb .plate { display: grid; gap: 6px; padding: 6px; border-radius: 10px; }
.brief-thumb .row-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.brief-thumb img { aspect-ratio: 3 / 2; object-fit: contain; }
.brief-thumb .row-2 img { aspect-ratio: 5 / 6; }
.brief-when { margin: 0 0 0.6em; color: var(--ink-3); font: 500 0.74rem var(--mono); letter-spacing: 0.08em; }
.brief h3 { font-size: clamp(1.2rem, 1.1rem + 0.45vw, 1.45rem); line-height: 1.2; letter-spacing: -0.012em; }
.brief .prose { max-width: 46em; margin-top: 0.7em; color: var(--ink-2); font-size: 0.95rem; line-height: 1.6; }
.brief .refs { margin-top: 1.1em; }
@media (max-width: 640px) { .brief { grid-template-columns: 1fr; } .brief-thumb { max-width: 300px; } }

/* ---------------------------------- research: frame, parts, folded content */
.frame { max-width: 40em; margin: 0; font: 420 clamp(1.25rem, 1.05rem + 0.95vw, 1.72rem)/1.36 var(--serif); letter-spacing: -0.012em; text-wrap: pretty; }
.parts-index { margin-top: clamp(28px, 4vw, 48px); border-bottom: 1px solid var(--rule-strong); }
.pi-row { display: grid; grid-template-columns: 104px minmax(0, 4fr) minmax(0, 7fr); gap: 4px 24px; align-items: baseline; padding: 14px 0; border-top: 1px solid var(--rule-strong); }
.pi-row .label { margin: 0; color: var(--gold-ink); }
.pi-title { margin: 0; color: var(--ink-2); font-size: 0.95rem; line-height: 1.45; }
.pi-row ul { margin: 0; padding: 0; list-style: none; }
.pi-row li + li { margin-top: 0.3em; }
.pi-row a { color: var(--ink); font: 480 1.1rem/1.3 var(--serif); text-decoration: none; background: linear-gradient(var(--gold), var(--gold)) 0 100% / 0 1.5px no-repeat; transition: background-size .3s cubic-bezier(.2, .7, .2, 1); }
.pi-row a:hover { color: var(--ink); background-size: 100% 1.5px; }
@media (max-width: 760px) { .pi-row { grid-template-columns: 84px minmax(0, 1fr); } .pi-row ul { grid-column: 1 / -1; } }

.part + .part, .part + .topics-title { margin-top: clamp(48px, 7vw, 96px); }
.part-title { display: flex; flex-wrap: wrap; align-items: baseline; gap: 4px 18px; margin: 0; padding-top: 14px; border-top: 1px solid var(--ink); color: var(--ink-2); font: 400 1rem/1.4 var(--sans); letter-spacing: 0; }
.part-title .label { margin: 0; color: var(--gold-ink); }
.part .topic { padding-top: clamp(26px, 3.6vw, 44px); }
/* each theme leads with a row of figures */
.lead-figs { margin-top: clamp(22px, 2.8vw, 34px); }
.lead-figs + .theme-body > .prose { margin-top: clamp(24px, 3vw, 36px); }
/* on a phone each theme opens on request (a script in the page closes them; without it they stay open) */
.theme-body > summary { display: flex; align-items: center; gap: 0.5em; width: fit-content; margin-top: 18px; padding: 0.5em 1.05em 0.5em 0.85em; border: 1px solid var(--rule-strong); border-radius: 999px; color: var(--ink); font: 500 0.86rem/1.3 var(--sans); cursor: pointer; list-style: none; }
.theme-body > summary::-webkit-details-marker { display: none; }
.theme-body > summary::before { content: "+"; color: var(--gold-ink); font: 400 1.25rem/0.8 var(--serif); transition: transform .25s cubic-bezier(.2, .7, .2, 1); }
.theme-body[open] > summary::before { transform: rotate(45deg); }
.theme-body[open] > summary .if-closed, .theme-body:not([open]) > summary .if-open { display: none; }
.lead-figs + .theme-body[open] > summary { margin-bottom: -6px; }
@media (min-width: 761px) { .theme-body[open] > summary { display: none; } }
@media (max-width: 760px) { .part .topic { padding-bottom: 30px; } }
/* figures and papers beyond the first few open with a click */
.fold { margin-top: 18px; border-block: 1px solid var(--rule); }
.fold + .fold { margin-top: -1px; }
.prose + .fold, .prose + .figs + .fold { margin-top: 26px; }
.fold summary { display: flex; align-items: baseline; gap: 0.55em; width: fit-content; padding: 11px 0; cursor: pointer; color: var(--ink-2); font: 500 0.86rem/1.4 var(--sans); list-style: none; }
.fold summary::-webkit-details-marker { display: none; }
.fold summary::before { content: "+"; width: 0.85em; color: var(--gold-ink); font: 400 1.25rem/1 var(--serif); transition: transform .25s cubic-bezier(.2, .7, .2, 1); }
.fold[open] summary::before { transform: rotate(45deg); }
.fold summary:hover { color: var(--ink); }
.fold .figs { margin-top: 6px; padding-bottom: 24px; }
.fold .refs { margin: 4px 0 18px; }

/* --------------------------------------------------------------- lightbox */
.lightbox { max-width: none; max-height: none; margin: auto; padding: 0; border: 0; background: transparent; }
.lightbox::backdrop { background: rgb(4 10 18 / .84); -webkit-backdrop-filter: blur(6px); backdrop-filter: blur(6px); }
@keyframes zoom-in { from { opacity: 0; transform: scale(.965); } }
.lightbox[open] img, .lightbox[open] video { animation: zoom-in .28s cubic-bezier(.2, .7, .2, 1); }
.lightbox img { display: block; max-width: min(94vw, 1500px); max-height: 90vh; padding: 14px; border-radius: 10px; background: #fff; cursor: zoom-out; }
.lightbox video { display: block; max-width: min(94vw, 1500px); max-height: 90vh; padding: 14px; border-radius: 10px; background: #fff; }

/* ----------------------------------------------------------------- footer */
.site-footer { margin-top: clamp(8px, 2vw, 32px); }
.horizon { position: relative; overflow: hidden; height: clamp(120px, 16vw, 250px); }
.horizon img { display: block; width: 100%; height: 100%; object-fit: cover; object-position: 50% 58%; transform: translateY(calc(var(--par, 0.5) * -22px + 11px)) scale(1.1); -webkit-mask-image: linear-gradient(to bottom, transparent 0, #000 62%); mask-image: linear-gradient(to bottom, transparent 0, #000 62%); }
.horizon::after { content: ""; position: absolute; inset: auto 0 0; height: 38%; background: linear-gradient(to bottom, transparent, var(--footer-bg)); }
.footer-main { padding: clamp(36px, 5vw, 64px) 0 28px; background: var(--footer-bg); color: #b5c0cc; font-size: 0.9rem; line-height: 1.6; }
.footer-main a { color: #dbe2e9; text-decoration-color: rgb(179 163 105 / .65); text-decoration-thickness: 1px; }
.footer-main a:hover { color: #fff; text-decoration-color: #fff; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1.25fr 1fr; gap: 32px clamp(24px, 4vw, 56px); }
.footer-grid p { margin: 0; }
.footer-grid ul { margin: 0; padding: 0; list-style: none; }
.footer-grid li { margin-bottom: 0.3em; }
.footer-name { margin-bottom: 0.3em !important; color: #fff; font: 480 1.5rem/1.2 var(--serif); letter-spacing: -0.012em; }
.footer-h { margin-bottom: 0.9em !important; color: #8794a2; font: 500 0.7rem/1.4 var(--mono); letter-spacing: 0.1em; text-transform: uppercase; }
.footer-base { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 6px 28px; margin-top: clamp(32px, 4vw, 52px); padding-top: 20px; border-top: 1px solid rgb(255 255 255 / .12); color: #8794a2; font: 500 0.7rem/1.5 var(--mono); letter-spacing: 0.04em; }
.footer-base p { margin: 0; }
@media (max-width: 860px) { .footer-grid { grid-template-columns: 1fr 1fr; } }
@media (max-width: 480px) { .footer-grid { grid-template-columns: 1fr; } }

.to-top { position: fixed; right: clamp(14px, 2.4vw, 34px); bottom: clamp(14px, 2.4vw, 34px); z-index: 30; display: grid; place-items: center; width: 44px; height: 44px; border: 1px solid var(--rule-strong); border-radius: 50%;
  background: var(--paper); background: color-mix(in srgb, var(--paper) 86%, transparent); -webkit-backdrop-filter: blur(10px); backdrop-filter: blur(10px); color: var(--ink-2);
  opacity: 0; transform: translateY(10px); pointer-events: none; transition: opacity .3s, transform .3s cubic-bezier(.2, .7, .2, 1), border-color .2s, color .2s; }
.to-top .i { width: 17px; height: 17px; transform: rotate(-90deg); }
.to-top.is-on { opacity: 1; transform: none; pointer-events: auto; }
.to-top:hover { border-color: var(--ink); color: var(--ink); }

/* a soft light that follows the pointer over a card (assets/site.js sets --mx and --my) */
[data-spot] { position: relative; isolation: isolate; }
[data-spot]::after { content: ""; position: absolute; inset: 0; z-index: -1; border-radius: inherit; opacity: 0; transition: opacity .4s; pointer-events: none;
  background: radial-gradient(340px circle at var(--mx, 50%) var(--my, 50%), rgb(179 163 105 / .2), transparent 65%); }
@media (hover: hover) { [data-spot]:hover::after { opacity: 1; } }

/* ----------------------------------------------------------------- motion */
@keyframes rise { from { opacity: 0; transform: translateY(14px); } }
@keyframes m-draw { to { stroke-dashoffset: 0; } }
@keyframes m-fade { from { opacity: 0; } }
@keyframes vt-out { to { opacity: 0; } }
@keyframes vt-in { from { opacity: 0; transform: translateY(8px); } }
@media (prefers-reduced-motion: no-preference) {
  /* pages cross-fade into each other while the header stays put (browsers without view transitions just navigate) */
  @view-transition { navigation: auto; }
  ::view-transition-old(root) { animation: vt-out .16s ease-in both; }
  ::view-transition-new(root) { animation: vt-in .36s cubic-bezier(.2, .7, .2, 1) both; }
  .site-header { view-transition-name: site-header; }
  /* switching the theme opens the new one as a circle from the button (assets/site.js) */
  html.theme-vt .site-header { view-transition-name: none; }
  html.theme-vt::view-transition-old(root), html.theme-vt::view-transition-new(root) { animation: none; mix-blend-mode: normal; }

  .hero-copy > *, .hero-pi, .page-head .label, .page-title, .page-intro { animation: rise .8s cubic-bezier(.2, .7, .2, 1) both; }
  .hero-copy > :nth-child(2), .page-title { animation-delay: .07s; }
  .hero-copy > :nth-child(3), .page-intro { animation-delay: .16s; }
  .hero-copy > :nth-child(4) { animation-delay: .25s; }
  .hero-pi { animation-delay: .2s; }

  .head-motif .m-s, .head-motif .m-m { stroke-dasharray: 1; stroke-dashoffset: 1; animation: m-draw 1.5s cubic-bezier(.3, .6, .2, 1) forwards; animation-delay: calc(var(--i, 0) * 45ms + 200ms); }
  .head-motif .m-m { animation-duration: 1.8s; animation-delay: .12s; }
  .head-motif .m-band { animation: m-fade 1.5s .7s both; }
  .head-motif .m-d, .head-motif .m-t { animation: m-fade .6s 1.2s both; }
}

.js .reveal { opacity: 0; transform: translateY(18px); transition: opacity .8s ease, transform .8s cubic-bezier(.2, .7, .2, 1); }
.js .reveal.is-in { opacity: 1; transform: none; }
.people .reveal:nth-child(4n + 2) { transition-delay: .07s; }
.people .reveal:nth-child(4n + 3) { transition-delay: .14s; }
.people .reveal:nth-child(4n + 4) { transition-delay: .21s; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition-duration: .01ms !important; transition-delay: 0s !important; }
  .js .reveal { opacity: 1; transform: none; }
}

/* ------------------------------------------------------------------ print */
@media print {
  :root { --paper: #fff; --paper-2: #fff; --ink: #000; --ink-2: #222; --ink-3: #444; }
  .site-header, .site-footer, .toolbar, .filter-status, .toc, .ensemble, .actions, .jump, .icon-links, .to-top, .head-motif, .cite { display: none !important; }
  .js .reveal { opacity: 1 !important; transform: none !important; }
  .section, .section-tight { padding-block: 16px; }
  .year { position: static; }
  a { text-decoration: none; }
  .pub, .news-item, .topic, .lib, .person { break-inside: avoid; }
}