/* dthcri.org — site styles
   Layout: one long page read like a dossier. A narrow margin column carries each
   section's label; the main column carries the content; each claim says where it
   can be checked. Left-aligned throughout. The only frosted-glass element is the
   caption on the hero photograph. */

:root {
  --paper: #ffffff;        /* page surface */
  --bg: #f4f9fa;           /* cool off-white, cyan bias */
  --ink: #0d2b2e;          /* body text */
  --teal: #0b4f55;         /* headings, rules, filled status */
  --teal-deep: #022c2e;    /* hero and footer bands */
  --teal-700: #06565b;
  --cyan: #06b6d4;         /* accent marks */
  --cyan-ink: #0e7490;     /* cyan readable as text on light */
  --cyan-soft: #a5ecf5;    /* Bangla title on the dark band */
  --tint: #e4f4f7;         /* cyan tint panels */
  --line: #cfe0e4;
  --muted: #4f6468;
  --band-fg: #f3fafb;
  --band-muted: #b9d7dc;
  --focus: #06b6d4;

  --font-en: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-bn: "Hind Siliguri", "Noto Sans Bengali", "Kalpurush", "SolaimanLipi", "Nirmala UI", system-ui, sans-serif;

  --display: clamp(2.25rem, 1.3rem + 3.4vw, 3.9rem);
  --h2: clamp(1.6rem, 1.2rem + 1.4vw, 2.3rem);
  --h3: 1.2rem;
  --body: 1.0625rem;
  --small: 0.92rem;
  --caption: 0.82rem;
  --wrap: 1120px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #0b3237; --bg: #072a2e; --ink: #e7f2f3; --teal: #a6dde4; --teal-deep: #04191b;
    --teal-700: #0a3d42; --cyan: #22d3ee; --cyan-ink: #6fe0f1; --cyan-soft: #a5ecf5; --tint: #0f3d43;
    --line: #1d5057; --muted: #a9c4c8; --band-fg: #f3fafb; --band-muted: #b9d7dc; --focus: #22d3ee;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --paper: #0b3237; --bg: #072a2e; --ink: #e7f2f3; --teal: #a6dde4; --teal-deep: #04191b;
  --teal-700: #0a3d42; --cyan: #22d3ee; --cyan-ink: #6fe0f1; --cyan-soft: #a5ecf5; --tint: #0f3d43;
  --line: #1d5057; --muted: #a9c4c8; --band-fg: #f3fafb; --band-muted: #b9d7dc; --focus: #22d3ee;
  color-scheme: dark;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: no-preference) { html { scroll-behavior: smooth; } }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-en);
  font-size: var(--body);
  line-height: 1.65;
  font-feature-settings: "cv11", "ss01";
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; }
a { color: var(--cyan-ink); text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: .18em; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; border-radius: 2px; }
h1, h2, h3, h4 { text-wrap: balance; }
p, li, dd { max-width: 68ch; }
[lang="bn"], .bn { font-family: var(--font-bn); line-height: 1.75; }
ul, ol { padding-left: 1.2rem; }
abbr[title] { text-decoration: none; }
.visually-hidden { position: absolute !important; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

.skip { position: absolute; left: 1rem; top: -3rem; background: var(--teal-deep); color: #fff; padding: .6rem .9rem; z-index: 100; border-radius: 4px; }
.skip:focus { top: 1rem; }

.wrap {
  max-width: var(--wrap);
  margin-inline: auto;
  padding-left: max(16px, env(safe-area-inset-left, 0px));
  padding-right: max(16px, env(safe-area-inset-right, 0px));
}

/* Utility bar + navigation */
.utility { background: var(--teal-deep); color: var(--band-muted); font-size: var(--caption); }
.utility .wrap { display: flex; justify-content: space-between; gap: 1rem; padding-block: .45rem; flex-wrap: wrap; }
.utility a { color: var(--band-fg); }

.nav { position: sticky; top: env(safe-area-inset-top, 0px); z-index: 50; background: var(--paper); border-bottom: 1px solid var(--line); }
.nav .wrap { display: flex; align-items: center; justify-content: space-between; gap: 1rem; min-height: 68px; padding-block: .5rem; }
.brand { display: flex; align-items: center; gap: .7rem; text-decoration: none; color: var(--ink); min-width: 0; flex: 1 1 auto; }
.brand svg { width: 38px; height: 38px; flex: none; }
.brand .name { display: block; min-width: 0; font-weight: 700; letter-spacing: .02em; line-height: 1.1; }
.brand .full { display: none; font-size: var(--caption); color: var(--muted); font-weight: 500; letter-spacing: 0; margin-top: .15rem; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
@media (min-width: 1200px) { .brand .full { display: block; } }
.menu { display: none; flex: none; }
.menu ul { list-style: none; margin: 0; padding: 0; display: flex; gap: 1.2rem; align-items: center; }
.menu a { text-decoration: none; color: var(--ink); font-weight: 500; font-size: .95rem; white-space: nowrap; }
.menu a:hover { color: var(--cyan-ink); text-decoration: underline; }
.menu .btn { padding: .55rem .9rem; font-size: .9rem; }
.nav-toggle { appearance: none; background: none; border: 1px solid var(--line); color: var(--ink); border-radius: 4px; padding: .5rem .7rem; font: inherit; font-size: .9rem; font-weight: 600; cursor: pointer; }
@media (min-width: 960px) {
  .menu { display: block; }
  .nav-toggle { display: none; }
}
@media (max-width: 959.98px) {
  .menu.open { display: block; position: absolute; left: 0; right: 0; top: 100%; background: var(--paper); border-bottom: 1px solid var(--line); box-shadow: 0 16px 32px -20px rgba(2, 44, 46, .35); }
  .menu.open ul { flex-direction: column; align-items: stretch; gap: 0; padding: .5rem max(16px, env(safe-area-inset-left, 0px)) 1rem; }
  .menu.open li { border-top: 1px solid var(--line); }
  .menu.open a { display: block; padding: .85rem 0; }
  .menu.open .btn { margin-top: .75rem; text-align: center; }
}

/* Buttons */
.btn { display: inline-block; padding: .8rem 1.15rem; border-radius: 4px; font-weight: 600; font-size: .95rem; text-decoration: none; border: 1px solid transparent; line-height: 1.2; }
.btn.primary { background: var(--cyan); color: #022c2e; }
.btn.primary:hover { filter: brightness(1.06); }
.btn.ghost { border-color: rgba(255, 255, 255, .4); color: var(--band-fg); }
.btn.ghost:hover { background: rgba(255, 255, 255, .08); }
.btn.solid { background: var(--teal); color: #fff; }
.btn.outline { border-color: var(--teal); color: var(--teal); }

/* Hero */
.hero { background: var(--teal-deep); color: var(--band-fg); padding-block: clamp(3rem, 7vw, 5.5rem) 0; overflow: hidden; }
.hero h1 { font-size: var(--display); line-height: 1.04; letter-spacing: -.022em; font-weight: 700; margin: 0; max-width: 17ch; }
.hero .bn-title { font-family: var(--font-bn); font-size: calc(var(--display) * .74); line-height: 1.35; font-weight: 600; color: var(--cyan-soft); margin: .6rem 0 0; max-width: 24ch; }
.hero .lede { font-size: 1.15rem; line-height: 1.6; max-width: 62ch; color: var(--band-muted); margin: 1.6rem 0 0; }
.hero .lede strong { color: var(--band-fg); font-weight: 600; }
.hero .cta { display: flex; flex-wrap: wrap; gap: .75rem; margin-top: 1.9rem; }
.hero-figure { margin: clamp(2.25rem, 5vw, 3.75rem) 0 0; position: relative; }
.hero-figure img { display: block; width: 100%; height: auto; border-radius: 6px 6px 0 0; }
.hero-figure figcaption { position: absolute; left: 1rem; bottom: 1rem; max-width: min(36rem, calc(100% - 2rem)); padding: .9rem 1.1rem; background: rgba(2, 44, 46, .58); backdrop-filter: blur(14px) saturate(1.2); -webkit-backdrop-filter: blur(14px) saturate(1.2); border: 1px solid rgba(255, 255, 255, .2); border-radius: 6px; font-size: var(--small); line-height: 1.45; color: #f3fafb; }
.hero-figure figcaption b { font-weight: 600; }
@media (max-width: 680px) {
  .hero-figure figcaption { position: static; max-width: none; border-radius: 0; background: var(--teal-700); border: 0; border-top: 1px solid rgba(255, 255, 255, .15); }
}

/* Sections */
.section { padding-block: clamp(3rem, 6vw, 5.5rem); border-top: 1px solid var(--line); }
.section.alt { background: var(--bg); }
.sec { display: grid; grid-template-columns: minmax(0, 1fr); gap: 1.25rem 3rem; }
@media (min-width: 900px) { .sec { grid-template-columns: 176px minmax(0, 1fr); } }
.margin { font-size: var(--small); color: var(--muted); }
.margin .label { font-weight: 600; color: var(--teal); display: block; }
.margin .note { display: block; margin-top: .4rem; line-height: 1.5; }
.body { min-width: 0; }
.body h2 { font-size: var(--h2); letter-spacing: -.015em; line-height: 1.15; margin: -.25rem 0 1.1rem; color: var(--teal); font-weight: 650; }
.body h3 { font-size: var(--h3); margin: 2rem 0 .5rem; color: var(--teal); font-weight: 650; }
.body h4 { font-size: var(--caption); color: var(--muted); font-weight: 600; margin: 0 0 .3rem; letter-spacing: .01em; }
.body p { margin: 0 0 1rem; }
.intro { font-size: 1.1rem; }
.lead-in { color: var(--muted); font-size: var(--small); margin-bottom: 1.5rem; }

/* The record (timeline) */
.record { list-style: none; margin: 0; padding: 0; border-top: 2px solid var(--teal); }
.record li { display: grid; grid-template-columns: minmax(0, 1fr); gap: .2rem 1.5rem; padding: 1rem 0; border-bottom: 1px solid var(--line); align-items: baseline; }
.record .when { font-variant-numeric: tabular-nums; color: var(--muted); font-size: var(--small); font-weight: 500; }
.record .what { margin: 0; max-width: none; }
.record .verify { font-size: var(--small); }
@media (min-width: 720px) {
  .record li { grid-template-columns: 140px minmax(0, 1fr) 165px; }
  .record .verify { text-align: right; }
}

/* Lines of work */
.lines { list-style: none; margin: 1.75rem 0 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 1.5rem 2.25rem; }
.lines li { border-top: 2px solid var(--line); padding-top: .8rem; max-width: none; }
.lines b { display: block; color: var(--teal); margin-bottom: .3rem; font-weight: 650; }
.lines p { font-size: var(--small); margin: 0; }

.bn-block { margin-top: 2rem; padding: 1.4rem 1.5rem; background: var(--tint); border-radius: 6px; }
.bn-block h3 { margin: 0 0 .5rem; font-size: 1.15rem; }
.bn-block p { margin: 0; font-size: 1.05rem; max-width: 70ch; }

/* People */
.person { display: grid; grid-template-columns: minmax(0, 1fr); gap: 1rem 1.6rem; padding: 1.75rem 0; border-top: 1px solid var(--line); }
@media (min-width: 640px) { .person { grid-template-columns: 112px minmax(0, 1fr); } }
.person img, .person .disc { width: 112px; height: 112px; border-radius: 50%; object-fit: cover; display: block; }
.person .disc { background: var(--tint); color: var(--teal); display: grid; place-items: center; font-weight: 700; font-size: 1.6rem; letter-spacing: .02em; }
.person h3 { margin: 0; font-size: 1.45rem; letter-spacing: -.01em; }
.person .bn-name { font-family: var(--font-bn); color: var(--muted); font-size: 1.05rem; margin: .1rem 0 .3rem; }
.person .role { color: var(--cyan-ink); font-weight: 600; margin: 0 0 .9rem; font-size: var(--small); }
.person ul.roles { margin: 0 0 1rem; padding-left: 1.1rem; font-size: var(--small); }
.person ul.roles li { margin-bottom: .25rem; }
.person .verify { font-size: var(--small); color: var(--muted); }

/* Programme */
.legend { display: flex; flex-wrap: wrap; gap: .6rem 1.2rem; align-items: center; font-size: var(--caption); color: var(--muted); margin: 0 0 1.25rem; }
.status { display: inline-flex; align-items: center; gap: .4rem; font-size: .78rem; font-weight: 600; padding: .22rem .62rem; border-radius: 999px; border: 1px solid transparent; letter-spacing: .01em; white-space: nowrap; }
.status.done { background: var(--teal); color: #fff; }
.status.live { background: var(--tint); color: var(--cyan-ink); border-color: var(--cyan); }
.status.prep { border-color: var(--teal); color: var(--teal); }
.status.plan { border: 1px dashed var(--muted); color: var(--muted); }
.study { display: grid; grid-template-columns: minmax(0, 1fr); gap: .8rem 2.25rem; padding: 1.4rem 0 1.6rem; border-top: 1px solid var(--line); }
.study:last-of-type { border-bottom: 1px solid var(--line); }
@media (min-width: 900px) { .study { grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr); } .study > header { grid-column: 1 / -1; } }
.study header { display: flex; flex-wrap: wrap; gap: .6rem 1rem; align-items: center; }
.study h3 { margin: 0; font-size: 1.22rem; }
.study p { font-size: var(--small); margin: 0; }
.panel { margin-top: 2.25rem; background: var(--teal-deep); color: var(--band-fg); padding: clamp(1.4rem, 3vw, 2.2rem); border-radius: 6px; }
.panel h3 { color: var(--cyan-soft); margin: 0 0 .75rem; font-size: 1.3rem; }
.panel p { color: var(--band-muted); margin: 0 0 .8rem; }
.panel p:last-child { margin-bottom: 0; }
.panel strong { color: var(--band-fg); font-weight: 600; }
.panel ol { color: var(--band-muted); margin: .5rem 0 1rem; }
.panel a { color: var(--cyan-soft); }

/* Platform */
.features { list-style: none; margin: 1.5rem 0 2.25rem; padding: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 1.25rem 2.25rem; }
.features li { border-top: 2px solid var(--line); padding-top: .75rem; font-size: var(--small); max-width: none; }
.features b { display: block; color: var(--teal); margin-bottom: .2rem; font-weight: 650; }
.tech { font-size: var(--small); color: var(--muted); margin-top: 1.5rem; }
.conf { display: grid; grid-template-columns: minmax(0, 1fr); gap: 1.5rem 2.25rem; margin: 2.25rem 0 0; padding: 1.75rem 0 0; border-top: 1px solid var(--line); }
@media (min-width: 800px) { .conf { grid-template-columns: minmax(0, 1fr) 280px; align-items: start; } }
.conf img { display: block; width: 100%; height: auto; border-radius: 6px; }
.conf figcaption { font-size: var(--caption); color: var(--muted); margin-top: .5rem; }
.conf h3 { margin-top: 0; }

/* Publications */
.pubs { list-style: none; margin: 0; padding: 0; }
.pubs li { padding: 1.1rem 0; border-top: 1px solid var(--line); display: grid; grid-template-columns: minmax(0, 1fr); gap: .25rem 1.5rem; }
.pubs li:last-child { border-bottom: 1px solid var(--line); }
@media (min-width: 720px) { .pubs li { grid-template-columns: 150px minmax(0, 1fr); } }
.pubs .kind { font-size: var(--small); color: var(--muted); font-weight: 500; }
.pubs b { color: var(--teal); font-weight: 650; }
.pubs p { margin: .15rem 0 0; font-size: var(--small); max-width: none; }

/* Governance */
.gov { list-style: none; margin: 0; padding: 0; display: grid; gap: 1.4rem; }
.gov li { padding-left: 1.1rem; border-left: 2px solid var(--cyan); max-width: 72ch; }
.gov b { display: block; color: var(--teal); font-weight: 650; margin-bottom: .2rem; }
.gov p { margin: 0; font-size: var(--small); }
.ids { font-variant-numeric: tabular-nums; }

/* Support */
.asks { list-style: none; margin: 1.5rem 0 0; padding: 0; display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 1.5rem 2.25rem; }
.asks li { border-top: 2px solid var(--teal); padding-top: .9rem; max-width: none; }
.asks h3 { margin: 0 0 .4rem; font-size: 1.15rem; }
.asks p { font-size: var(--small); margin: 0 0 .6rem; }
.two { display: grid; grid-template-columns: minmax(0, 1fr); gap: 1.25rem 2.25rem; margin-top: 2rem; }
@media (min-width: 800px) { .two { grid-template-columns: 1fr 1fr; } }
.two > div { background: var(--tint); padding: 1.3rem 1.4rem; border-radius: 6px; }
.two h3 { margin: 0 0 .5rem; font-size: 1.1rem; }
.two p, .two li { font-size: var(--small); }
.two ul { margin: 0; padding-left: 1.1rem; }
.cta-row { display: flex; flex-wrap: wrap; gap: .75rem 1.25rem; align-items: center; margin-top: 2rem; }
.cta-row .or { color: var(--muted); font-size: var(--small); }

/* Contact */
.contact { display: grid; grid-template-columns: minmax(0, 1fr); gap: 1.25rem 2.5rem; margin: 0; }
@media (min-width: 720px) { .contact { grid-template-columns: 1fr 1fr; } }
.contact div { min-width: 0; }
.contact dt { font-size: var(--caption); color: var(--muted); font-weight: 600; margin-bottom: .15rem; }
.contact dd { margin: 0 0 1rem; }
.copy { appearance: none; font: inherit; font-size: .78rem; font-weight: 600; color: var(--cyan-ink); background: var(--tint); border: 1px solid var(--line); border-radius: 4px; padding: .15rem .5rem; margin-left: .5rem; cursor: pointer; vertical-align: middle; }
.copy:hover { border-color: var(--cyan); }

/* Footer */
.footer { background: var(--teal-deep); color: var(--band-muted); font-size: var(--caption); padding-block: 2.5rem 3rem; }
.footer .wrap { display: grid; grid-template-columns: minmax(0, 1fr); gap: 1.5rem 3rem; }
@media (min-width: 800px) { .footer .wrap { grid-template-columns: 1.4fr 1fr; } }
.footer b { color: var(--band-fg); font-weight: 600; }
.footer a { color: var(--band-fg); }
.footer p { margin: 0 0 .5rem; max-width: 70ch; }
.footer ul { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: .4rem 1.25rem; }
.footer .legal { margin-top: 1rem; }