/* DueTrack Studio — one stylesheet, no framework.
   Warm paper and ink, one emerald accent; the app icons supply the colour. */

:root {
  --paper: #F6F4EF;
  --surface: #FFFFFF;
  --ink: #15130F;
  --muted: #5E5A52;
  --line: #E4E0D6;
  --accent: #0B6E4F;
  --on-accent: #FFFFFF;
  --shadow: 0 1px 2px rgba(21, 19, 15, .04), 0 8px 24px rgba(21, 19, 15, .06);
  --radius: 20px;
  --serif: "Instrument Serif", "New York", Georgia, serif;
  --sans: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #0F0E0C;
    --surface: #1A1815;
    --ink: #F2EFE8;
    --muted: #A39E93;
    --line: #2A2823;
    --accent: #4FC59A;
    --on-accent: #0F0E0C;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 8px 24px rgba(0, 0, 0, .35);
  }
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 17px/1.6 var(--sans);
  -webkit-font-smoothing: antialiased;
}
html[lang="bn"] body, [lang="bn"] { font-family: "Hind Siliguri", "Kohinoor Bangla", var(--sans); }
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; }
a:hover { color: var(--accent); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 6px; }

.wrap { width: min(1120px, 100% - 32px); margin-inline: auto; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 16px; background: var(--surface); padding: 8px 12px; z-index: 10; }
.muted { color: var(--muted); }
.small { font-size: 14px; }
.fine { font-size: 13px; }

h1, h2, h3 { line-height: 1.15; margin: 0 0 .5em; letter-spacing: -0.01em; }
h1, h2 { font-family: var(--serif); font-weight: 400; }
h1 { font-size: clamp(40px, 6.4vw, 76px); letter-spacing: -0.02em; }
h2 { font-size: clamp(30px, 3.6vw, 42px); }
h3 { font-size: 18px; font-weight: 600; }
html[lang="bn"] h1, html[lang="bn"] h2 { font-family: "Hind Siliguri", "Kohinoor Bangla", var(--sans); font-weight: 600; letter-spacing: 0; }
html[lang="bn"] h1 { font-size: clamp(32px, 5vw, 56px); }
em { font-style: italic; color: var(--accent); }
p { margin: 0 0 1em; }
.lede { font-size: clamp(18px, 2vw, 21px); color: var(--muted); max-width: 40em; }
.eyebrow { text-transform: uppercase; letter-spacing: .12em; font-size: 12px; font-weight: 600; color: var(--muted); margin-bottom: 14px; }

/* Header & footer */
.site-header { position: sticky; top: 0; z-index: 5; background: color-mix(in srgb, var(--paper) 86%, transparent); backdrop-filter: saturate(1.4) blur(14px); -webkit-backdrop-filter: saturate(1.4) blur(14px); border-bottom: 1px solid var(--line); }
.bar { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 600; text-decoration: none; letter-spacing: -0.01em; }
.mark { display: inline-grid; place-items: center; width: 30px; height: 30px; border-radius: 9px; background: var(--ink); color: var(--paper); font: 20px/1 var(--serif); }
.site-header nav { display: flex; gap: 22px; font-size: 15px; }
.site-header nav a { text-decoration: none; color: var(--muted); }
.site-header nav a:hover { color: var(--ink); }
.site-footer { border-top: 1px solid var(--line); margin-top: 96px; padding: 48px 0 40px; }
.foot { display: grid; gap: 24px; }
.foot-apps { display: flex; flex-wrap: wrap; gap: 8px 18px; font-size: 15px; }
.foot-apps a { color: var(--muted); text-decoration: none; }
.brand.small { margin-bottom: 8px; }

/* Buttons */
.btn { display: inline-flex; align-items: center; gap: 10px; padding: 13px 22px; border-radius: 999px; background: var(--ink); color: var(--paper); text-decoration: none; font-weight: 600; font-size: 16px; transition: transform .15s ease, opacity .15s ease; }
.btn:hover { color: var(--paper); transform: translateY(-1px); opacity: .92; }
.btn.ghost { background: transparent; color: var(--ink); border: 1px solid var(--line); }
.btn.ghost:hover { color: var(--ink); border-color: var(--ink); }

/* Home */
.hero { padding: clamp(64px, 12vw, 140px) 0 clamp(40px, 6vw, 72px); }
.hero h1 { max-width: 12em; }
.apps { padding-top: 32px; }
.group { margin-top: 40px; }
.group h3 { font-size: 13px; text-transform: uppercase; letter-spacing: .12em; color: var(--muted); font-weight: 600; margin-bottom: 14px; }
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)); gap: 14px; }
.card { display: flex; align-items: center; gap: 16px; padding: 18px; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); text-decoration: none; box-shadow: var(--shadow); transition: transform .18s ease, border-color .18s ease; }
.card:hover { transform: translateY(-2px); border-color: color-mix(in srgb, var(--ink) 25%, var(--line)); color: inherit; }
.card-text { display: grid; gap: 2px; flex: 1; min-width: 0; }
.card-text strong { font-size: 17px; }
.card-text span { color: var(--muted); font-size: 14px; line-height: 1.4; }
.chev { color: var(--muted); transition: transform .18s ease; }
.card:hover .chev { transform: translateX(3px); color: var(--accent); }
.icon { width: 64px; height: 64px; border-radius: 22.5%; flex: none; box-shadow: 0 0 0 1px rgba(0, 0, 0, .06); }
.icon.xl { width: 120px; height: 120px; }
.principles { margin-top: 96px; }
.icon-row { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 44px; }
.icon-row a { transition: transform .18s ease; }
.icon-row a:hover { transform: translateY(-3px) rotate(-2deg); }
.icon-row .icon { width: 72px; height: 72px; }
.grid3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 32px; margin-top: 24px; }
.grid3 p { color: var(--muted); }

/* App page */
.crumbs { padding-top: 24px; font-size: 14px; color: var(--muted); }
.crumbs a { color: var(--muted); text-decoration: none; }
.app-hero { display: grid; grid-template-columns: auto 1fr; gap: 32px; align-items: start; padding: 40px 0 48px; }
.app-hero h1 { font-size: clamp(36px, 5vw, 60px); }
.cta { display: flex; flex-wrap: wrap; align-items: center; gap: 14px 18px; margin-top: 24px; }
.shots { overflow-x: auto; scroll-snap-type: x mandatory; padding: 8px 0 24px; scrollbar-width: none; }
.shots::-webkit-scrollbar { display: none; }
.shots-track { display: flex; gap: 20px; width: max-content; padding-inline: max(16px, calc((100vw - 1120px) / 2)); }
.shots img { width: clamp(220px, 26vw, 300px); border-radius: 28px; box-shadow: var(--shadow); border: 1px solid var(--line); scroll-snap-align: start; background: var(--surface); }
.prose { max-width: 760px; }
.summary { font-size: clamp(19px, 2.2vw, 24px); line-height: 1.5; margin: 48px 0; }
section > h2 { margin-top: 72px; }
.feats { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 14px; }
.feat { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px 24px; }
.feat p { color: var(--muted); margin: 0; font-size: 16px; }
.split { display: grid; grid-template-columns: 1.2fr 1fr; gap: 40px; align-items: start; }
.split > div:not(.panel) > h2 { margin-top: 72px; }
.panel { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 28px 30px; margin-top: 72px; }
.panel h2 { margin-top: 0; font-size: 30px; }
.ticks { list-style: none; padding: 0; margin: 0; display: grid; gap: 12px; }
.ticks li { position: relative; padding-left: 30px; }
.ticks li::before { content: ""; position: absolute; left: 0; top: .45em; width: 16px; height: 9px; border-left: 2px solid var(--accent); border-bottom: 2px solid var(--accent); transform: rotate(-45deg); }
.faq { max-width: 820px; }
details { border-bottom: 1px solid var(--line); padding: 18px 0; }
details:first-of-type { border-top: 1px solid var(--line); }
summary { cursor: pointer; font-weight: 600; list-style: none; display: flex; justify-content: space-between; gap: 16px; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; color: var(--muted); font-weight: 400; font-size: 22px; line-height: 1; }
details[open] summary::after { content: "–"; }
details p { color: var(--muted); margin: 12px 0 0; }
.closing { text-align: center; margin-top: 96px; padding: 56px 24px; background: var(--surface); border: 1px solid var(--line); border-radius: 28px; display: grid; justify-items: center; }
.closing h2 { margin: 16px 0 20px; }
.legal { font-size: 14px; color: var(--muted); margin-top: 12px; }
.legal a { color: var(--muted); }
.disclaimer { font-size: 13px; color: var(--muted); max-width: 40em; margin: 8px 0 0; }
.page { padding: 72px 0 0; }
.page ul { padding-left: 1.2em; }
.page li { margin-bottom: .5em; }

@media (max-width: 760px) {
  body { font-size: 16px; }
  .site-header nav { gap: 16px; }
  .app-hero { grid-template-columns: 1fr; gap: 20px; padding-top: 24px; }
  .icon.xl { width: 96px; height: 96px; }
  .split { grid-template-columns: 1fr; gap: 0; }
  .cards, .feats { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; scroll-behavior: auto !important; }
}

/* Guides */
.guide h1 { font-size: clamp(36px, 5vw, 56px); }
.guide h2 { margin-top: 48px; font-size: clamp(26px, 3vw, 34px); }
.guide ul, .guide ol { padding-left: 1.3em; }
.guide li { margin-bottom: .45em; }
.answer { font-size: clamp(19px, 2.2vw, 22px); line-height: 1.55; padding: 22px 24px; background: var(--surface); border: 1px solid var(--line); border-left: 4px solid var(--accent); border-radius: 14px; }
.app-box { display: flex; gap: 18px; align-items: flex-start; margin: 56px 0; padding: 24px; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); }
.app-box p { color: var(--muted); margin: 4px 0 12px; }
.app-box .more { margin-left: 12px; font-size: 15px; }
.guide-list { list-style: none; padding: 0; display: grid; gap: 10px; }
.guide-list li { display: grid; gap: 2px; padding: 14px 18px; background: var(--surface); border: 1px solid var(--line); border-radius: 14px; }
.guide-list a { font-weight: 600; text-decoration: none; }
.guide-list span { color: var(--muted); font-size: 15px; }
.uses .chips { display: flex; flex-wrap: wrap; gap: 8px; }
.uses .chips span { padding: 6px 12px; border: 1px solid var(--line); border-radius: 999px; background: var(--surface); font-size: 15px; }
.guide { padding-top: 32px; }
.guide-links { list-style: none; padding: 0; display: grid; gap: 8px; }
.guide-links a { display: block; padding: 12px 16px; background: var(--surface); border: 1px solid var(--line); border-radius: 12px; text-decoration: none; font-weight: 600; }
.sources { margin-top: 48px; font-size: 15px; color: var(--muted); }
.sources h2 { font-size: 22px; }
.sources a { color: var(--muted); }