/* srijitmukherjee.com: the srijitmath.com brand. White, black, and one accent. */
:root {
  --bg: #ffffff; --ink: #0b0b0c; --muted: #5d6067; --line: #e6e6e8; --soft: #f6f6f7;
  --accent: #e8590c; --accent-soft: #fff1e8;
  --wrap: 1020px;
}
* { box-sizing: border-box; }
html { background: var(--bg); -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--ink); min-height: 100vh; display: flex; flex-direction: column;
  font: 17px/1.6 "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  -webkit-font-smoothing: antialiased; }
main { flex: 1; }
a { color: var(--ink); }
img { max-width: 100%; height: auto; }
::selection { background: var(--accent-soft); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 4px; }

.btn { display: inline-block; border: 1.5px solid var(--ink); background: var(--ink); color: #fff; border-radius: 999px;
  padding: .6em 1.4em; font-weight: 600; text-decoration: none; line-height: 1.3; transition: filter .15s; }
.btn.accent { background: var(--accent); border-color: var(--accent); }
.btn:hover { filter: brightness(1.08); }
.quiet { color: var(--ink); font-weight: 600; text-decoration: none; border-bottom: 1.5px solid var(--line); transition: border-color .15s; }
.quiet:hover { border-color: var(--accent); }
.kicker { font-size: 13px; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); margin: 0 0 18px; }
.wrap { max-width: var(--wrap); margin: 0 auto; padding: 0 24px; }

/* ---------- header ---------- */
.top { position: sticky; top: 0; z-index: 5; display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 14px max(24px, calc((100vw - var(--wrap)) / 2 + 24px)); background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); border-bottom: 1px solid var(--line); }
.brand { font-weight: 700; text-decoration: none; letter-spacing: -.01em; font-size: 17px; white-space: nowrap; }
.brand i { font-style: normal; color: var(--accent); }
.nav { display: flex; gap: 28px; }
.nav a { text-decoration: none; color: var(--muted); font-weight: 500; font-size: 15px; padding: 4px 0;
  border-bottom: 1.5px solid transparent; transition: color .15s, border-color .15s; }
.nav a:hover { color: var(--ink); }
.nav a[aria-current] { color: var(--ink); border-color: var(--accent); }
.menu { display: none; position: relative; }
.menu summary { list-style: none; cursor: pointer; font-size: 20px; line-height: 1; padding: 6px 10px;
  border: 1px solid var(--line); border-radius: 10px; }
.menu summary::-webkit-details-marker { display: none; }
.menulist { position: absolute; right: 0; top: calc(100% + 8px); min-width: 180px; background: var(--bg); padding: 6px;
  border: 1px solid var(--line); border-radius: 12px; box-shadow: 0 10px 30px rgba(0, 0, 0, .08); display: flex; flex-direction: column; }
.menulist a { text-decoration: none; padding: 10px 14px; border-radius: 8px; font-weight: 500; }
.menulist a:hover { background: var(--soft); }
@media (max-width: 600px) {
  .top { padding: 12px 16px; }
  .nav { display: none; }
  .menu { display: block; }
}

/* ---------- home ---------- */
.home { padding-bottom: 72px; }
.hero { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 56px; align-items: center; padding: clamp(48px, 8vh, 96px) 0 64px; }
.hero h1 { font-size: clamp(46px, 7vw, 84px); line-height: 1.02; letter-spacing: -.045em; font-weight: 800; margin: 0 0 26px; }
.hl { position: relative; display: inline-block; z-index: 0; }
.scribble { position: absolute; left: -3%; width: 106%; bottom: -.02em; height: .62em; z-index: -1; overflow: visible; }
.mark { fill: none; stroke: var(--accent); stroke-width: 22; stroke-linecap: round; opacity: .32;
  stroke-dasharray: 420; stroke-dashoffset: 420; animation: mark .9s cubic-bezier(.6, .1, .3, 1) .35s forwards; }
.mark.two { stroke-width: 9; opacity: .5; animation-delay: .95s; animation-duration: .7s; }
@keyframes mark { to { stroke-dashoffset: 0; } }
@media (prefers-reduced-motion: reduce) { .mark { animation: none; stroke-dashoffset: 0; } }
.hero .sub { font-size: 21px; line-height: 1.5; color: var(--muted); max-width: 560px; margin: 0 0 34px; text-wrap: pretty; }
.cta { display: flex; flex-wrap: wrap; gap: 14px 24px; align-items: center; }
.cta .btn { font-size: 17px; padding: .7em 1.6em; }
.portrait { width: 100%; aspect-ratio: 642 / 748; object-fit: cover; border-radius: 22px; display: block;
  box-shadow: 0 1px 0 var(--line), 0 24px 60px -24px rgba(0, 0, 0, .25); }

.news { border: 1px solid var(--line); border-radius: 16px; padding: 18px 22px; margin: 0 0 24px; background: var(--soft); }
.news p { margin: 0; display: flex; gap: 14px; align-items: baseline; font-size: 16px; line-height: 1.55; }
.news p + p { margin-top: 10px; }
.tag { flex: none; background: var(--accent-soft); color: var(--accent); font-weight: 700; font-size: 13px;
  padding: 2px 10px; border-radius: 999px; letter-spacing: .02em; }

.split { display: grid; grid-template-columns: 180px minmax(0, 1fr); gap: 32px; padding: 44px 0; border-top: 1px solid var(--line); }
.hero + .split, .news + .split { border-top: 0; padding-top: 24px; }
.label { font-size: 13px; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); margin: 6px 0 0; }
.prose { font-size: 18px; line-height: 1.75; max-width: 700px; }
.prose p { margin: 0 0 1.1em; }
.prose a, .facts a, .news a { text-decoration-color: var(--accent); text-underline-offset: 3px; }
.chips { list-style: none; padding: 0; margin: 22px 0 0; display: flex; flex-wrap: wrap; gap: 8px; }
.chips li { border: 1px solid var(--line); border-radius: 999px; padding: 4px 14px; font-size: 14px; font-weight: 500; }
.facts { display: grid; grid-template-columns: 110px minmax(0, 1fr); gap: 12px 20px; margin: 0; font-size: 17px; max-width: 700px; }
.facts dt { color: var(--muted); }
.facts dd { margin: 0; }

.cards { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.card { display: flex; flex-direction: column; gap: 6px; text-decoration: none; border: 1.5px solid var(--line);
  border-radius: 16px; overflow: hidden; padding: 0 22px 22px; transition: border-color .15s, transform .15s; }
.card:hover { border-color: var(--accent); transform: translateY(-2px); }
.card img { margin: 0 -22px 16px; width: calc(100% + 44px); max-width: none; aspect-ratio: 16 / 9; object-fit: cover;
  object-position: top left; border-bottom: 1px solid var(--line); background: var(--soft); }
.card-k { font-size: 12px; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); }
.card b { font-size: 22px; letter-spacing: -.02em; line-height: 1.25; }
.card-d { color: var(--muted); font-size: 16px; line-height: 1.5; }
.card small { color: var(--accent); font-size: 15px; font-weight: 700; margin-top: auto; padding-top: 10px; }

@media (max-width: 820px) {
  .hero { grid-template-columns: minmax(0, 1fr) 220px; gap: 32px; }
  .split { grid-template-columns: minmax(0, 1fr); gap: 14px; }
}
@media (max-width: 600px) {
  .wrap { padding: 0 16px; }
  .hero { grid-template-columns: minmax(0, 1fr); gap: 0; padding: 32px 0 40px; }
  .portrait { order: -1; width: 132px; border-radius: 18px; margin-bottom: 26px; }
  .hero h1 { font-size: 46px; margin-bottom: 18px; }
  .hero .sub { font-size: 18px; margin-bottom: 26px; }
  .news { padding: 14px 16px; }
  .news p { flex-direction: column; gap: 6px; }
  .split { padding: 32px 0; }
  .prose { font-size: 17px; }
  .facts { grid-template-columns: minmax(0, 1fr); gap: 2px; }
  .facts dd { margin-bottom: 12px; }
  .cards { grid-template-columns: minmax(0, 1fr); }
}

/* ---------- list pages: Publications, Teaching ---------- */
.list { padding-top: 64px; padding-bottom: 80px; }
.list-head { padding-bottom: 28px; border-bottom: 1px solid var(--line); }
.list-head h1 { font-size: clamp(38px, 5.4vw, 56px); line-height: 1.05; letter-spacing: -.035em; font-weight: 800; margin: 0; }
.intro { font-size: 19px; line-height: 1.6; color: var(--muted); max-width: 720px; }
.intro p { margin: 16px 0 0; }
.intro:empty { display: none; }
.items { list-style: none; margin: 0; padding: 0; }
.items li { border-bottom: 1px solid var(--line); }
.item { display: grid; grid-template-columns: 260px minmax(0, 1fr); gap: 32px; padding: 32px 0; text-decoration: none; align-items: start; }
.item img { width: 100%; aspect-ratio: 16 / 10; object-fit: cover; object-position: top left; border-radius: 12px;
  border: 1px solid var(--line); background: var(--soft); transition: transform .2s; }
.item:hover img { transform: translateY(-2px); }
.item-meta { display: block; font-size: 13px; font-weight: 600; color: var(--muted); margin-bottom: 6px; }
.item h2 { font-size: 23px; line-height: 1.3; letter-spacing: -.015em; margin: 0; transition: color .15s; }
.item:hover h2 { color: var(--accent); }
.item p { color: var(--muted); font-size: 16px; line-height: 1.65; margin: 10px 0 0; }
.item small { display: inline-block; color: var(--accent); font-weight: 700; font-size: 15px; margin-top: 14px; }
.more { margin: 32px 0 0; }
@media (max-width: 700px) {
  .list { padding-top: 36px; }
  .item { grid-template-columns: minmax(0, 1fr); gap: 16px; padding: 26px 0; }
  .item h2 { font-size: 20px; }
}

/* ---------- blog: the srijitmath.com reading column ---------- */
.blog-post, .blog-list { max-width: 720px; margin: 0 auto; padding: 48px 20px 96px; }
.blog-post .kicker a { color: var(--accent); text-decoration: none; font-weight: 600; font-size: 14px; letter-spacing: .02em; text-transform: none; }
.blog-post h1, .blog-list h1 { font-size: 44px; line-height: 1.15; font-weight: 800; letter-spacing: -.02em; margin: 8px 0 0; }
.blog-post .dek, .blog-list .dek { font-size: 21px; line-height: 1.45; color: var(--muted); margin: 12px 0 0; }
.blog-list .list-head .dek { font-size: 18px; line-height: 1.6; }
.blog-list .list-head .dek p { margin: 0; }
.blog-post .byline { color: var(--muted); font-size: 14px; margin: 18px 0 0; padding-bottom: 22px; border-bottom: 1px solid var(--line); }
.post-body { font-size: 19px; line-height: 1.75; margin-top: 32px; overflow-wrap: break-word; }
.post-body p { margin: 0 0 1.2em; }
.post-body h2 { font-size: 28px; line-height: 1.25; margin: 1.8em 0 .5em; letter-spacing: -.01em; }
.post-body h3 { font-size: 22px; line-height: 1.3; margin: 1.6em 0 .4em; }
.post-body a { color: var(--ink); text-decoration-color: var(--accent); text-underline-offset: 3px; }
.post-body ul, .post-body ol { padding-left: 1.3em; margin: 0 0 1.2em; }
.post-body li { margin: .3em 0; }
.post-body li::marker { color: var(--muted); }
.post-body blockquote { margin: 1.6em 0; padding: 2px 0 2px 20px; border-left: 3px solid var(--accent); color: #2b2c30; }
.post-body blockquote p:last-child { margin-bottom: 0; }
.post-body img { display: block; max-width: 100%; height: auto; margin: 1.6em auto; border-radius: 6px; }
.post-body figure { margin: 2em 0; }
.post-body figcaption { text-align: center; color: var(--muted); font-size: 15px; margin-top: 10px; }
.post-body pre { background: var(--soft); padding: 14px 16px; border-radius: 8px; overflow-x: auto; font-size: 15px; line-height: 1.5; }
.post-body code { font-size: .88em; }
.post-body :not(pre) > code { background: var(--soft); padding: 1px 5px; border-radius: 4px; }
.post-body .katex-display { overflow-x: auto; overflow-y: hidden; padding: 4px 0; }
.post-body table { border-collapse: collapse; display: block; overflow-x: auto; margin: 0 0 1.2em; }
.post-body td, .post-body th { border: 1px solid var(--line); padding: 6px 12px; }
.post-body th { background: var(--soft); }
.post-body hr { border: 0; border-top: 1px solid var(--line); margin: 2.4em 0; }
.post-body details { border: 1px solid var(--line); border-radius: 12px; margin: 0 0 12px; transition: border-color .15s; }
.post-body details:hover { border-color: var(--accent); }
.post-body summary { cursor: pointer; padding: 14px 18px; font-size: 17px; line-height: 1.5; list-style: none; }
.post-body summary::-webkit-details-marker { display: none; }
.post-body summary::after { content: " →"; color: var(--accent); font-weight: 700; }
.cite a { text-decoration: none; color: var(--accent); font-weight: 600; font-size: .8em; margin-left: 1px; }
.refs h2 { font-size: 20px; margin: 48px 0 12px; padding-top: 24px; border-top: 1px solid var(--line); }
.refs ol, .sheet-refs ol { font-size: 15px; line-height: 1.7; color: var(--muted); padding-left: 1.3em; margin: 0; }
.refs li, .sheet-refs li { margin-bottom: 6px; }
.post-foot { margin-top: 48px; padding-top: 22px; border-top: 1px solid var(--line); color: var(--muted); font-size: 16px; }
.post-foot a { color: var(--ink); text-decoration-color: var(--accent); text-underline-offset: 3px; font-weight: 600; }
.draft-banner { background: var(--accent-soft); color: var(--accent); font-weight: 600; font-size: 14px; padding: 10px 14px; border-radius: 10px; margin: 0 0 20px; }

.posts { list-style: none; margin: 0; padding: 0; }
.posts li { border-bottom: 1px solid var(--line); }
.posts li a { display: block; padding: 26px 0; text-decoration: none; color: var(--ink); }
.posts h2 { font-size: 24px; line-height: 1.3; margin: 0; letter-spacing: -.01em; transition: color .15s; }
.posts li a:hover h2 { color: var(--accent); }
.posts .dek { font-size: 17px; margin: 6px 0 0; }
.posts .byline { color: var(--muted); font-size: 14px; margin: 10px 0 0; }
.posts .none { color: var(--muted); padding: 26px 0; }
.feed { margin: 28px 0 0; font-size: 14px; }
.feed a { color: var(--muted); }
@media (max-width: 640px) {
  .blog-post, .blog-list { padding: 28px 16px 72px; }
  .blog-post h1, .blog-list h1 { font-size: 32px; }
  .blog-post .dek, .blog-list .dek { font-size: 18px; }
  .post-body { font-size: 17px; }
  .post-body h2 { font-size: 24px; }
  .posts h2 { font-size: 21px; }
}

/* <details> pop-up */
.overlay { position: fixed; inset: 0; z-index: 20; background: rgba(11, 11, 12, .4); display: flex; align-items: flex-start;
  justify-content: center; padding: 40px 16px; overflow-y: auto; }
.overlay[hidden] { display: none; }
.sheet { background: var(--bg); border-radius: 16px; width: min(720px, 100%); margin: auto; overflow: hidden;
  box-shadow: 0 30px 80px -20px rgba(0, 0, 0, .35); }
.sheet-head { display: flex; gap: 12px; align-items: flex-start; padding: 18px 20px 14px; border-bottom: 1px solid var(--line); }
#details-popup-title { flex: 1; font-weight: 700; line-height: 1.5; }
.x { background: none; border: 0; font-size: 18px; line-height: 1; color: var(--muted); cursor: pointer; padding: 4px; }
.x:hover { color: var(--ink); }
.sheet-body { margin: 0; padding: 18px 20px; font-size: 17px; }
.sheet-body > br:first-child { display: none; }
.sheet-refs { padding: 16px 20px 20px; border-top: 1px solid var(--line); }
.sheet-refs h3 { margin: 0 0 8px; font-size: 16px; }

/* ---------- 404 ---------- */
.notfound { padding-top: 14vh; padding-bottom: 14vh; }
.notfound h1 { font-size: clamp(38px, 6vw, 64px); letter-spacing: -.04em; line-height: 1.05; margin: 0 0 14px; }
.notfound .sub { color: var(--muted); font-size: 19px; margin: 0 0 28px; }

/* ---------- footer ---------- */
.foot { border-top: 1px solid var(--line); }
.foot-in { max-width: var(--wrap); margin: 0 auto; padding: 32px 24px 40px; display: flex; flex-wrap: wrap; gap: 14px 28px; align-items: center; }
.foot-mail { font-weight: 600; text-decoration: none; border-bottom: 1.5px solid var(--line); }
.foot-mail:hover { border-color: var(--accent); }
.foot-links { display: flex; flex-wrap: wrap; gap: 8px 22px; }
.foot-links a { color: var(--muted); text-decoration: none; font-size: 15px; }
.foot-links a:hover { color: var(--ink); }
.foot .fine { margin: 0 0 0 auto; color: var(--muted); font-size: 13px; }
@media (max-width: 600px) {
  .foot-in { padding: 28px 16px 36px; flex-direction: column; align-items: flex-start; }
  .foot .fine { margin: 0; }
}