@font-face {
  font-family: "Source Serif 4";
  src: url("fonts/source-serif-400.woff") format("woff");
  font-style: normal;
  font-weight: 400;
  font-display: swap;
}
@font-face {
  font-family: "IBM Plex Sans";
  src: url("fonts/plex-sans-400.woff") format("woff");
  font-style: normal;
  font-weight: 400;
  font-display: swap;
}
@font-face {
  font-family: "IBM Plex Sans";
  src: url("fonts/plex-sans-600.woff") format("woff");
  font-style: normal;
  font-weight: 600;
  font-display: swap;
}
@font-face {
  font-family: "IBM Plex Mono";
  src: url("fonts/plex-mono-400.woff") format("woff");
  font-style: normal;
  font-weight: 400;
  font-display: swap;
}

:root {
  --paper: #f7f7f4;
  --ink: #20252b;
  --annotation: #536e7a;
  --graphite: #4f5962;
  --rule: #d5d9d8;
  --code-paper: #eeefeb;
  --selection: #dbe3e7;
  --serif: "Source Serif 4", Georgia, serif;
  --sans: "IBM Plex Sans", Arial, sans-serif;
  --mono: "IBM Plex Mono", Consolas, monospace;
  --page-width: 1160px;
  --space-1: .25rem;
  --space-2: .5rem;
  --space-3: .75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4rem;
  --space-9: 5rem;
}

* { box-sizing: border-box; }
html { scroll-behavior: auto; scroll-padding-top: var(--space-6); }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 400 16px/1.75 var(--sans);
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-underline-offset: .3em; }
a:hover { color: var(--annotation); }
:focus-visible { outline: 2px solid var(--annotation); outline-offset: 5px; }
::selection { background: var(--selection); color: var(--ink); }
.page-width { width: calc(100% - 96px); max-width: var(--page-width); margin-inline: auto; }
h1, h2, h3, p, figure { margin: 0; }
h1, h2, h3 { font-family: var(--serif); font-weight: 400; }
h1 { font-size: clamp(3.25rem, 5vw, 4.5rem); line-height: 1.08; letter-spacing: -.045em; text-wrap: balance; }
h2 { font-size: clamp(1.85rem, 2.8vw, 2.5rem); line-height: 1.2; letter-spacing: -.03em; }
var { font-family: var(--serif); }
sup { line-height: 0; }
.eyebrow, .plate-label, .publication-label, .caption-label, .figure-kind {
  font: 400 .65rem/1.7 var(--mono);
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--annotation);
}
.eyebrow { margin-bottom: var(--space-5); }
.skip-link { position: absolute; left: var(--space-4); top: -6rem; z-index: 2; padding: var(--space-3) var(--space-4); background: var(--ink); color: var(--paper); }
.skip-link:focus { top: var(--space-4); color: var(--paper); }

/* The masthead uses the quiet hierarchy of a research publication. */
.site-header { padding-top: var(--space-5); }
.masthead-note { display: flex; justify-content: space-between; gap: var(--space-6); color: var(--annotation); font: 400 .6rem/1.6 var(--mono); }
.masthead-main { display: flex; justify-content: space-between; align-items: center; gap: var(--space-6); padding: var(--space-5) 0; border-bottom: 1px solid var(--ink); }
.wordmark { display: inline-flex; align-items: center; gap: var(--space-1); font: 400 2.2rem/1.25 var(--serif); letter-spacing: -.045em; text-decoration: none; white-space: nowrap; }
.brand-mark { display: block; flex: none; width: 1.25em; height: 1.25em; }
.wordmark-to { font-style: italic; }
.site-header nav { display: flex; gap: var(--space-6); }
.site-header nav a { display: inline-flex; align-items: center; min-height: 44px; font-size: .85rem; text-decoration: none; }
.site-header nav a:hover { text-decoration: underline; }
.external-link { gap: var(--space-2); }

.hero { padding: var(--space-7) 0 var(--space-8); }
.hero-eyebrow { margin-bottom: var(--space-6); }
.hero-introduction { display: grid; grid-template-columns: 1.7fr 1fr; gap: var(--space-8); align-items: end; margin-bottom: var(--space-7); }
.hero h1 { max-width: 19ch; }
.hero-abstract { padding-bottom: var(--space-1); }
.hero-description { max-width: 34em; font-size: 1rem; line-height: 1.85; color: var(--graphite); }
.hero-actions { display: flex; flex-wrap: wrap; gap: var(--space-3) var(--space-5); align-items: center; margin-top: var(--space-5); }
.primary-link, .quiet-link { display: inline-flex; align-items: center; justify-content: space-between; gap: var(--space-4); min-height: 44px; font-size: .82rem; text-decoration: none; }
.primary-link { border-bottom: 1px solid var(--ink); font-weight: 600; }
.primary-link:hover { border-color: var(--annotation); }
.quiet-link:hover { text-decoration: underline; }

/* One continuous plate makes the model-to-code translation inspectable. */
.model-figure { margin: 0; min-width: 0; }
.figure-heading { display: flex; align-items: baseline; justify-content: space-between; gap: var(--space-5); padding: var(--space-3) 0; border-top: 1px solid var(--ink); border-bottom: 1px solid var(--rule); }
.figure-heading > span:first-child { font: 400 1.15rem/1.5 var(--serif); }
.figure-kind { font-size: .57rem; text-align: right; }
.model-plate { display: grid; grid-template-columns: 1.05fr .85fr 1.1fr; padding-block: var(--space-5); border-bottom: 1px solid var(--rule); }
.plate-panel { min-width: 0; padding-inline: var(--space-5); }
.plate-panel:first-child { padding-left: 0; }
.plate-panel:last-child { padding-right: 0; }
.plate-panel + .plate-panel { border-left: 1px solid var(--rule); }
.plate-label { display: flex; align-items: baseline; gap: var(--space-3); font-size: .63rem; letter-spacing: .025em; }
.plate-label > span:first-child { color: var(--graphite); }
.code-language { margin-left: auto; font-size: .55rem; text-transform: none; letter-spacing: 0; }
.governing-equation { padding: var(--space-6) 0 var(--space-5); }
.governing-equation math { font-size: clamp(1.25rem, 2.1vw, 1.6rem); margin: 0; }
.model-name { font-size: .8rem; line-height: 1.7; margin-bottom: var(--space-2); }
.model-assumptions { color: var(--graphite); font-size: .76rem; line-height: 1.8; }
.model-symbols { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-3) var(--space-2); margin: var(--space-5) 0 0; }
.model-symbols > div { display: flex; gap: var(--space-2); align-items: baseline; }
.model-symbols dt { font-size: 1.1rem; }
.model-symbols dd { margin: 0; font-size: .63rem; line-height: 1.7; }
.model-symbols dd > span { display: block; font: 400 .55rem/1.9 var(--mono); color: var(--annotation); white-space: nowrap; }
.state-equations { display: flex; flex-direction: column; align-items: flex-start; gap: var(--space-4); padding: var(--space-5) 0; }
.state-equations math { font-size: 1.4rem; margin: 0; }
.state-definition { font-size: .75rem; line-height: 1.85; }
.plate-note { font-size: .75rem; line-height: 1.8; color: var(--graphite); margin-top: var(--space-3); }
.code-panel pre { max-width: 100%; margin: var(--space-5) 0 0; padding: var(--space-3) var(--space-4); background: var(--code-paper); overflow-x: auto; tab-size: 4; }
.code-panel pre code { font: 400 .75rem/2 var(--mono); }
.model-figure figcaption { display: grid; grid-template-columns: 1.05fr 1.95fr; gap: var(--space-5); padding-top: var(--space-4); font-size: .69rem; line-height: 1.85; color: var(--graphite); }
.caption-label { font-size: .57rem; letter-spacing: .02em; padding-top: var(--space-1); }
.model-figure figcaption code { font-family: var(--mono); font-size: .9em; }

/* A marginal column accompanies the numbered method, as in technical notes. */
.method-section, .areas-section, .about-section { display: grid; grid-template-columns: 1fr 1.8fr; gap: var(--space-9); border-top: 1px solid var(--rule); padding-block: var(--space-8); }
.section-heading h2 { max-width: 16ch; }
.section-intro { font-size: .9rem; line-height: 1.85; color: var(--graphite); margin-top: var(--space-5); max-width: 31em; }
.marginal-note { margin-top: var(--space-6); padding-left: var(--space-4); border-left: 1px solid var(--annotation); font: 400 1rem/1.65 var(--serif); color: var(--annotation); }
.method-list { list-style: none; padding: 0; margin: 0; }
.method-list li { display: grid; grid-template-columns: 2rem 1fr; gap: var(--space-4); padding-block: var(--space-5); border-bottom: 1px solid var(--rule); }
.method-list li:first-child { padding-top: 0; }
.stage-number { font: 400 .69rem/2 var(--mono); color: var(--annotation); }
.method-list h3 { font: 600 .9rem/1.5 var(--sans); margin-bottom: var(--space-2); }
.method-list p { font-size: .83rem; line-height: 1.85; color: var(--graphite); max-width: 65em; }
.method-note { font-size: .74rem; line-height: 1.8; color: var(--annotation); margin-top: var(--space-5); }

.projects-section { border-top: 1px solid var(--rule); padding-block: var(--space-8); }
.section-heading-row { display: flex; align-items: flex-end; justify-content: space-between; gap: var(--space-7); }
.section-heading-row h2 { max-width: none; }
.section-description { font-size: .82rem; line-height: 1.8; color: var(--graphite); }
.project-list { margin-top: var(--space-7); }
.project-entry { display: grid; grid-template-columns: 1fr 1.8fr; gap: var(--space-9); padding-top: var(--space-6); border-top: 1px solid var(--rule); }
.project-entry + .project-entry { margin-top: var(--space-7); }
.publication-label { font-size: .58rem; }
.topics { list-style: none; padding: 0; margin: var(--space-5) 0 0; display: flex; flex-direction: column; align-items: flex-start; gap: var(--space-1); }
.topics li { font-size: .76rem; color: var(--graphite); }
.project-detail h3 { font-size: clamp(1.9rem, 3.1vw, 2.7rem); line-height: 1.2; letter-spacing: -.03em; max-width: 25ch; margin-bottom: var(--space-5); }
.project-detail > p { font-size: .91rem; line-height: 1.9; color: var(--graphite); }
.project-links { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-3) var(--space-5); margin-top: var(--space-5); }
.project-links a { display: inline-flex; align-items: center; gap: var(--space-2); min-height: 44px; font-size: .78rem; text-decoration: none; }
.project-links a:hover { text-decoration: underline; }
.publication-note { font-size: .9rem; color: var(--graphite); margin-top: var(--space-6); max-width: 60em; }

.areas-section h2 { font-size: 1.9rem; }
.areas-section > div > p:last-child { font-size: .82rem; color: var(--graphite); margin-top: var(--space-4); }
.areas-section ul { list-style: none; padding: 0; margin: 0; }
.areas-section li { display: flex; align-items: baseline; gap: var(--space-5); padding-block: var(--space-3); border-bottom: 1px solid var(--rule); font: 400 1.3rem/1.6 var(--serif); }
.areas-section li:first-child { padding-top: 0; }
.area-index { color: var(--annotation); font: 400 .6rem/1.8 var(--mono); }
.about-section { padding-bottom: var(--space-9); }
.about-section h2 { font-size: 2rem; max-width: 21ch; }
.about-copy > p:first-child { font: 400 1.4rem/1.65 var(--serif); letter-spacing: -.01em; }
.about-secondary { margin-top: var(--space-5); font-size: .85rem; line-height: 1.9; color: var(--graphite); }
.about-copy .quiet-link { margin-top: var(--space-4); }
.site-footer { display: flex; justify-content: space-between; align-items: center; gap: var(--space-5); padding-block: var(--space-5); border-top: 1px solid var(--ink); color: var(--graphite); font-size: .69rem; }
.site-footer a { display: inline-flex; align-items: center; min-height: 44px; }
.footer-wordmark { gap: var(--space-1); font: 400 1.1rem/1.5 var(--serif); color: var(--ink); text-decoration: none; }

@media (max-width: 1100px) {
  .page-width { width: calc(100% - 64px); }
  .hero-introduction { gap: var(--space-7); }
  .hero-actions { column-gap: var(--space-4); }
  .plate-panel { padding-inline: var(--space-4); }
  .model-plate { grid-template-columns: 1.05fr .8fr 1.15fr; }
  .governing-equation math { font-size: 1.6rem; }
  .model-symbols > div { display: block; }
  .model-symbols dt { line-height: 1.3; }
  .code-panel pre { padding-inline: var(--space-3); }
  .method-section, .areas-section, .about-section, .project-entry { gap: var(--space-7); }
}

@media (max-width: 850px) {
  .masthead-note { font-size: .55rem; }
  .masthead-note > span:last-child { display: none; }
  .wordmark { font-size: 2rem; }
  .site-header nav { gap: var(--space-5); }
  .hero-introduction { grid-template-columns: 1.35fr 1fr; }
  .hero h1 { font-size: 3.4rem; }
  .hero-description { font-size: .92rem; }
  .hero-actions { gap: var(--space-2) var(--space-4); }
  .hero-actions a { font-size: .77rem; }
  .figure-kind { max-width: 26ch; }
  .model-plate { grid-template-columns: 1.1fr .9fr; }
  .plate-panel { padding-inline: var(--space-5); }
  .plate-panel:nth-child(2) { padding-right: 0; }
  .code-panel { grid-column: 1 / -1; display: grid; grid-template-columns: 1.1fr .9fr; column-gap: var(--space-5); border-top: 1px solid var(--rule); padding: var(--space-5) 0 0; margin-top: var(--space-5); }
  .plate-panel.code-panel { border-left: 0; }
  .code-panel .plate-label { grid-column: 1; align-self: start; }
  .code-panel pre { grid-column: 1; grid-row: 2 / 4; font-size: .75rem; }
  .code-panel pre code { font-size: .75rem; }
  .code-panel .plate-note { grid-column: 2; grid-row: 2; align-self: center; padding-left: var(--space-4); margin: 0; max-width: 27ch; font-size: .78rem; }
  .governing-equation math { font-size: 1.6rem; }
  .model-symbols > div { display: flex; }
  .model-figure figcaption { grid-template-columns: 1fr; gap: var(--space-2); }
  .method-section, .areas-section, .about-section, .project-entry { grid-template-columns: 1fr 1.65fr; }
  .section-heading h2 { font-size: 1.9rem; }
}

@media (max-width: 640px) {
  .page-width { width: calc(100% - 40px); }
  .site-header { padding-top: var(--space-4); }
  .masthead-note { font-size: .52rem; letter-spacing: -.01em; }
  .masthead-main { display: block; padding: var(--space-4) 0 var(--space-2); }
  .wordmark { font-size: 2rem; }
  .site-header nav { justify-content: space-between; gap: var(--space-4); margin-top: var(--space-2); }
  .site-header nav a { font-size: .8rem; }
  .hero { padding: var(--space-6) 0 var(--space-7); }
  .hero-eyebrow { font-size: .54rem; line-height: 1.9; max-width: 52ch; margin-bottom: var(--space-5); }
  .hero-introduction { grid-template-columns: 1fr; gap: var(--space-5); margin-bottom: var(--space-6); }
  .hero h1 { font-size: clamp(2.8rem, 9vw, 3.6rem); max-width: 19ch; }
  .hero-description { font-size: .96rem; }
  .hero-actions { gap: var(--space-3) var(--space-6); margin-top: var(--space-4); }
  .hero-actions a { font-size: .82rem; }
  .figure-heading { display: block; }
  .figure-heading > span:first-child { display: block; }
  .figure-kind { display: block; text-align: left; max-width: none; font-size: .54rem; margin-top: var(--space-1); }
  .model-plate { grid-template-columns: 1fr; padding-block: 0; }
  .plate-panel { padding: var(--space-5) 0; }
  .plate-panel + .plate-panel { border-left: 0; border-top: 1px solid var(--rule); }
  .plate-label { font-size: .63rem; }
  .governing-equation { padding-block: var(--space-5); }
  .governing-equation math { font-size: 1.45rem; }
  .model-name { font-size: .83rem; }
  .model-assumptions { font-size: .78rem; }
  .model-symbols dd { font-size: .69rem; }
  .model-symbols dd > span { font-size: .6rem; }
  .state-panel { display: block; }
  .state-equations { padding: var(--space-5) 0; gap: var(--space-3); }
  .state-equations math { font-size: 1.5rem; }
  .state-definition { font-size: .75rem; }
  .state-panel .plate-note { font-size: .73rem; }
  .state-panel .plate-note br { display: none; }
  .code-panel { display: block; margin-top: 0; }
  .code-panel pre { padding: var(--space-4); margin-top: var(--space-4); }
  .code-panel pre code { font-size: .75rem; }
  .code-panel .plate-note { padding: 0; margin-top: var(--space-3); max-width: none; font-size: .73rem; }
  .model-figure figcaption { font-size: .72rem; padding-top: var(--space-4); }
  .caption-label { font-size: .57rem; }
  .method-section, .areas-section, .about-section { grid-template-columns: 1fr; gap: var(--space-6); padding-block: var(--space-7); }
  .section-heading h2 { max-width: 24ch; font-size: 2rem; }
  .section-intro { font-size: .86rem; margin-top: var(--space-4); }
  .marginal-note { margin-top: var(--space-5); font-size: .93rem; }
  .marginal-note br { display: none; }
  .method-list li { grid-template-columns: 1.5rem 1fr; gap: var(--space-3); }
  .method-list p { font-size: .84rem; }
  .method-note { font-size: .75rem; }
  .projects-section { padding-block: var(--space-7); }
  .section-heading-row { display: block; }
  .section-description { margin-top: var(--space-4); font-size: .85rem; }
  .section-description br { display: none; }
  .project-list { margin-top: var(--space-6); }
  .project-entry { grid-template-columns: 1fr; gap: var(--space-5); padding-top: var(--space-5); }
  .topics { flex-direction: row; flex-wrap: wrap; gap: var(--space-1) var(--space-3); margin-top: var(--space-2); }
  .topics li { font-size: .67rem; }
  .project-detail h3 { font-size: 2rem; margin-bottom: var(--space-4); }
  .project-detail > p { font-size: .88rem; }
  .project-links { margin-top: var(--space-4); gap: var(--space-2) var(--space-4); }
  .project-links a { font-size: .76rem; }
  .areas-section li { font-size: 1.2rem; gap: var(--space-4); }
  .about-copy > p:first-child { font-size: 1.3rem; }
  .about-secondary { font-size: .85rem; }
  .site-footer { flex-wrap: wrap; gap: var(--space-2) var(--space-5); padding-block: var(--space-4); }
  .site-footer > span { order: 3; width: 100%; }
  .site-footer > a:last-child { margin-left: auto; }
}

@media (max-width: 359px) {
  .page-width { width: calc(100% - 32px); }
  .hero h1 { font-size: 2.65rem; }
  .hero-eyebrow { font-size: .52rem; }
  .code-panel pre { padding-inline: var(--space-3); }
}

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