:root {
  --light: #fefefe;
  --lightgray: #f5f4f2;
  --gray: #a8a29e;
  --darkgray: #57534e;
  --dark: #1a1a1a;
  --secondary: #2563a8;
  --tertiary: #7c6f5e;
  --highlight: rgba(37, 99, 168, 0.08);
  --text-highlight: #fef3c7;
  --post-link: #5b9bd5;

  --font-header: "Schibsted Grotesk", system-ui, -apple-system, sans-serif;
  --font-body: "Source Sans Pro", system-ui, -apple-system, sans-serif;
  --font-code: "IBM Plex Mono", ui-monospace, monospace;
}

html[data-theme="dark"] {
  --light: #1c1917;
  --lightgray: #292524;
  --gray: #78716c;
  --darkgray: #d6d3d1;
  --dark: #fafaf9;
  --secondary: #5b9bd5;
  --tertiary: #a8a29e;
  --highlight: rgba(91, 155, 213, 0.1);
  --text-highlight: #44403c;
  --post-link: #7fbbe8;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--light);
  color: var(--dark);
  font-family: var(--font-body);
  font-size: 18px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--secondary); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3, h4, h5, h6 { font-family: var(--font-header); color: var(--dark); line-height: 1.25; }
h1 { font-size: 1.9rem; margin: 0 0 0.5rem; }
h2 { font-size: 1.35rem; margin: 2rem 0 0.75rem; }
h3 { font-size: 1.1rem; margin: 1.5rem 0 0.5rem; }

code { font-family: var(--font-code); font-size: 0.92em; background: var(--lightgray); padding: 0.1em 0.3em; border-radius: 3px; }
pre { background: var(--lightgray); padding: 1rem; border-radius: 6px; overflow-x: auto; }
pre code { background: none; padding: 0; }

blockquote {
  border-left: 3px solid var(--gray);
  margin: 1rem 0;
  padding: 0.25rem 1rem;
  color: var(--darkgray);
}

img { max-width: 100%; height: auto; display: block; margin: 1rem auto; }

hr { border: 0; border-top: 1px solid var(--lightgray); margin: 2rem 0; }

/* header */
.site-header {
  max-width: 920px;
  margin: 0 auto;
  padding: 1.5rem 1.5rem 0.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.site-title {
  font-family: var(--font-header);
  font-weight: 600;
  font-size: 1.5rem;
  letter-spacing: -0.015em;
  color: var(--dark);
}
.site-title:hover { text-decoration: none; color: var(--secondary); }
.site-nav { display: flex; gap: 1.25rem; align-items: center; }
.site-nav a { color: var(--darkgray); font-size: 0.95rem; }
.site-nav a:hover { color: var(--secondary); text-decoration: none; }
#theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  font-size: 1.1rem;
  color: var(--darkgray);
  padding: 0;
}
#theme-toggle:hover { color: var(--secondary); }

/* layout */
main.page {
  max-width: 1480px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}

.post-wrap {
  display: grid;
  grid-template-columns: 260px minmax(0, 800px) 260px;
  column-gap: 4rem;
  justify-content: center;
  align-items: start;
}
@media (max-width: 1460px) {
  .post-wrap { grid-template-columns: 240px minmax(0, 800px); column-gap: 3rem; }
  .post-wrap .sidenotes { display: none; }
  .post-wrap .post .footnotes { display: block; }
}
@media (max-width: 1040px) {
  .post-wrap { grid-template-columns: minmax(0, 800px); justify-content: center; }
  .post-wrap .toc { display: none; }
}

.sidenotes {
  position: relative;
  font-size: 0.85rem;
  line-height: 1.45;
  color: var(--darkgray);
}
.sidenote {
  position: absolute;
  left: 0;
  right: 0;
  padding: 0.4rem 0.6rem;
  border-left: 2px solid var(--lightgray);
  transition: border-color 0.15s, background 0.15s;
}
.sidenote.active {
  border-left-color: var(--secondary);
  background: var(--highlight);
}
.sidenote .num {
  font-weight: 600;
  color: var(--gray);
  margin-right: 0.35rem;
  font-variant-numeric: tabular-nums;
}
.sidenote p { margin: 0; display: inline; }
.sidenote a[data-footnote-backref] { display: none; }

/* Hide the bottom footnotes list when sidenotes are visible (desktop). */
@media (min-width: 1461px) {
  .post .footnotes { display: none; }
}

/* footnote reference in body */
sup a[data-footnote-ref] {
  text-decoration: none;
  color: var(--secondary);
  padding: 0 0.15rem;
  border-radius: 3px;
}
sup a[data-footnote-ref].active {
  background: var(--highlight);
}

.toc {
  position: sticky;
  top: 1.5rem;
  align-self: start;
  font-size: 0.88rem;
  color: var(--darkgray);
  max-height: calc(100vh - 3rem);
  overflow-y: auto;
}
.toc h3 {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--gray);
  margin: 0 0 0.5rem;
  font-weight: 500;
}
.toc ul { list-style: none; padding: 0; margin: 0; border-left: 1px solid var(--lightgray); }
.toc li { line-height: 1.35; }
.toc li a {
  display: block;
  padding: 0.25rem 0.75rem;
  color: var(--darkgray);
  border-left: 2px solid transparent;
  margin-left: -1px;
}
.toc li a:hover { color: var(--secondary); text-decoration: none; }
.toc li.toc-3 a { padding-left: 1.5rem; font-size: 0.84rem; color: var(--gray); }
.toc li a.active { color: var(--secondary); border-left-color: var(--secondary); }

h2, h3 { position: relative; }
h2:hover .anchor, h3:hover .anchor { opacity: 1; }
.anchor {
  position: absolute;
  left: -1.25rem;
  opacity: 0;
  color: var(--gray);
  text-decoration: none;
  font-weight: 400;
  transition: opacity 0.15s;
}
.anchor:hover { text-decoration: none; color: var(--secondary); }

main.home {
  max-width: 800px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}

/* blog index */
.blog-grid {
  max-width: 1080px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 5rem;
}
@media (max-width: 720px) {
  .blog-grid { grid-template-columns: 1fr; gap: 1.5rem; }
}
.blog-col-title {
  font-size: 1.5rem;
  font-weight: 600;
  margin: 0 0 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--lightgray);
  letter-spacing: -0.015em;
}

/* about */
.about { margin-bottom: 3rem; }
.about p { margin: 0 0 0.9rem; }
.about .socials {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  font-size: 0.95rem;
}
.about .socials a {
  color: var(--darkgray);
}
.about .socials a:hover { color: var(--secondary); text-decoration: none; }

/* papers */
.papers { margin-bottom: 3rem; }
.papers h2 {
  font-size: 1.1rem;
  font-weight: 500;
  margin: 0 0 1.25rem;
  letter-spacing: -0.01em;
}
.papers-list { list-style: none; padding: 0; margin: 0; }
.paper {
  padding: 0.9rem 0;
  border-top: 1px solid var(--lightgray);
}
.paper:last-child { border-bottom: 1px solid var(--lightgray); }
.paper-title {
  font-size: 1.02rem;
  line-height: 1.35;
  margin-bottom: 0.25rem;
}
.paper-title a { color: var(--secondary); }
.paper-title a:hover { color: var(--post-link); text-decoration: none; }
.paper-title a.external::after { content: "\00a0↗"; font-size: 0.8em; color: var(--gray); }
.paper-authors {
  font-size: 0.92rem;
  color: var(--darkgray);
  margin-bottom: 0.15rem;
}
.paper-venue {
  font-size: 0.88rem;
  color: var(--gray);
  font-style: italic;
  margin-bottom: 0.4rem;
}
.paper-desc {
  font-size: 0.95rem;
  color: var(--darkgray);
  line-height: 1.5;
}
.paper-authors:empty,
.paper-venue:empty,
.paper-desc:empty { display: none; }

.post-list { margin-bottom: 2.5rem; }
.post-list h2 {
  font-size: 1.1rem;
  font-weight: 500;
  margin: 0 0 1rem;
  letter-spacing: -0.01em;
}
/* On the home page the section headings are top-level, so they match the size of the
   blog page's column headings. */
main.home .papers h2,
main.home .post-list h2 {
  font-size: 1.5rem;
  font-weight: 600;
  letter-spacing: -0.015em;
  margin-bottom: 1.25rem;
}
.post-list .section-note {
  font-size: 0.82rem;
  color: var(--gray);
  margin: -0.7rem 0 0.9rem;
}
.post-list ul { list-style: none; padding: 0; margin: 0; }
.post-list li {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  padding: 0.4rem 0;
}
.post-list .meta {
  font-size: 0.82rem;
  color: var(--gray);
}
.post-list a {
  color: var(--secondary);
  font-size: 1rem;
}
.post-list .note {
  font-size: 0.82rem;
  color: var(--gray);
}
.post-list a:hover { color: var(--post-link); text-decoration: none; }
.post-list a.external::after {
  content: "\00a0↗";
  font-size: 0.8em;
  color: var(--gray);
}
.talk-note {
  color: var(--gray);
  font-size: 0.88rem;
}

/* post */
.post-header { margin-bottom: 2rem; }
.post-note { color: var(--gray); font-size: 0.9rem; margin: 0.35rem 0 0; }
.post-meta { color: var(--gray); font-size: 0.9rem; margin: 0.25rem 0 0; }
.post-meta .tag {
  display: inline-block;
  background: var(--lightgray);
  border-radius: 3px;
  padding: 0.05rem 0.4rem;
  margin-right: 0.25rem;
  font-size: 0.8rem;
  color: var(--darkgray);
}

.post-body p { margin: 0.9rem 0; }
.post-body ul, .post-body ol { padding-left: 1.5rem; }

/* footnotes */
.footnotes { font-size: 0.9rem; color: var(--darkgray); border-top: 1px solid var(--lightgray); margin-top: 3rem; padding-top: 1rem; }
.footnotes ol { padding-left: 1.2rem; }

/* katex */
.katex-display { overflow-x: auto; overflow-y: hidden; padding: 0.25rem 0; }