:root {
  --bg: #f7fafc;
  --surface: #ffffff;
  --surface-soft: #f0fdfa;
  --text: #102033;
  --muted: #526173;
  --border: #dce7ef;
  --primary: #0f766e;
  --primary-dark: #115e59;
  --primary-soft: #ccfbf1;
  --accent: #f59e0b;
  --shadow: 0 18px 50px rgba(15, 23, 42, 0.08);
  --radius: 24px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: Arial, "Noto Sans Bengali", "Hind Siliguri", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
  text-rendering: optimizeLegibility;
}

body:has(.site-nav.is-open) { overflow: hidden; }

a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--primary-dark); }
a:focus-visible, button:focus-visible { outline: 3px solid var(--accent); outline-offset: 3px; }

img, svg { max-width: 100%; }

.container { width: min(1120px, 92%); margin: 0 auto; }
.narrow { width: min(820px, 92%); }
.compact { max-width: 820px; }

.skip-link {
  position: absolute;
  left: 16px;
  top: -80px;
  z-index: 100;
  background: var(--primary);
  color: #fff;
  padding: 10px 14px;
  border-radius: 10px;
}
.skip-link:focus { top: 12px; }

.site-header {
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(14px);
}

.nav {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--primary-dark);
  font-size: 24px;
  font-weight: 900;
  letter-spacing: -0.03em;
}
.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--primary), #14b8a6);
  color: #fff;
  font-size: 17px;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 8px;
}
.site-nav a, .lang-toggle {
  border: 0;
  background: transparent;
  border-radius: 999px;
  color: #334155;
  cursor: pointer;
  font: inherit;
  font-weight: 700;
  padding: 9px 12px;
}
.site-nav a:hover, .lang-toggle:hover { background: var(--surface-soft); color: var(--primary-dark); }
.lang-toggle { border: 1px solid var(--border); background: var(--surface); min-width: 70px; }

.nav-toggle { display: none; }

.hero, .page-hero {
  background:
    radial-gradient(circle at 12% 10%, rgba(20, 184, 166, 0.18), transparent 32%),
    linear-gradient(135deg, #ecfeff 0%, #f8fafc 62%, #fff7ed 100%);
}
.hero { padding: clamp(60px, 9vw, 110px) 0; }
.page-hero { padding: clamp(48px, 8vw, 88px) 0; }

.hero-grid, .split {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(280px, 0.85fr);
  gap: clamp(24px, 5vw, 56px);
  align-items: center;
}

.eyebrow {
  color: var(--primary);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.12em;
  margin: 0 0 12px;
  text-transform: uppercase;
}
.eyebrow.light { color: #a7f3d0; }

h1, h2, h3 { letter-spacing: -0.035em; color: inherit; }
h1 { font-size: clamp(38px, 7vw, 72px); line-height: 1.02; margin: 0 0 22px; max-width: 820px; }
h2 { font-size: clamp(28px, 4vw, 44px); line-height: 1.12; margin: 0 0 18px; }
h3 { font-size: 21px; line-height: 1.25; margin: 0 0 10px; }
p { margin: 0 0 16px; }
.hero-text, .section-heading p, .page-hero p { color: var(--muted); font-size: clamp(17px, 2vw, 20px); max-width: 720px; }

.actions { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 30px; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 12px 20px;
  border-radius: 999px;
  font-weight: 800;
  border: 1px solid transparent;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}
.button:hover { transform: translateY(-1px); }
.primary { background: var(--primary); color: white; box-shadow: 0 12px 24px rgba(15, 118, 110, 0.2); }
.primary:hover { background: var(--primary-dark); color: white; }
.secondary { background: white; color: var(--primary-dark); border-color: #99f6e4; }
.disabled { opacity: 0.7; cursor: not-allowed; pointer-events: none; }
.note { color: #64748b; margin-top: 16px; }

.hero-card, .card, .center-card, .support-card {
  background: rgba(255,255,255,0.92);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.hero-card, .card { padding: clamp(22px, 3vw, 30px); }
.hero-card h2 { font-size: clamp(25px, 3vw, 34px); }
.center-card, .support-card { padding: clamp(26px, 5vw, 42px); }
.center-card { text-align: center; }

.status-pill {
  display: inline-flex;
  align-items: center;
  border-radius: 999px;
  background: var(--primary-soft);
  color: var(--primary-dark);
  font-size: 13px;
  font-weight: 800;
  padding: 6px 10px;
  margin-bottom: 16px;
}
.check-list { list-style: none; padding: 0; margin: 18px 0 0; display: grid; gap: 10px; }
.check-list li { position: relative; padding-left: 28px; }
.check-list li::before { content: "✓"; position: absolute; left: 0; color: var(--primary); font-weight: 900; }

.section { padding: clamp(58px, 8vw, 88px) 0; }
.section-heading { max-width: 760px; margin-bottom: 26px; }
.cards { display: grid; gap: 18px; margin-top: 28px; }
.cards.four { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.cards.three { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.card p { color: var(--muted); }
.featured { border-color: #5eead4; box-shadow: 0 24px 60px rgba(15, 118, 110, 0.12); }

.highlight { background: linear-gradient(135deg, #0f766e, #0f4f49); color: white; }
.highlight p { color: #d1fae5; font-size: 18px; max-width: 780px; }
.steps { display: grid; gap: 14px; }
.steps div {
  display: flex;
  align-items: center;
  gap: 14px;
  background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.18);
  border-radius: 18px;
  padding: 16px;
}
.steps strong { display: grid; place-items: center; width: 38px; height: 38px; border-radius: 50%; background: white; color: var(--primary-dark); }

.download-cta { background: #ffffff; }
.muted { background: #eef7f6; }
.support-card { display: grid; gap: 18px; justify-items: start; }
.support-card strong { font-size: clamp(20px, 3vw, 28px); overflow-wrap: anywhere; }

.legal-page { max-width: 900px; }
.legal-page h2 { font-size: clamp(23px, 3vw, 30px); margin-top: 30px; }
.legal-page p, .legal-page li { color: var(--muted); }
.legal-meta { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 18px; }

.download-box .card { max-width: 780px; margin-inline: auto; }
.requirements { margin: 0; padding-left: 20px; color: var(--muted); }

footer { background: #0f172a; color: #cbd5e1; padding: 30px 0; }
.footer { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
.footer p { margin: 0; }
footer a { color: #99f6e4; }

@media (max-width: 960px) {
  .cards.four { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .hero-grid, .split { grid-template-columns: 1fr; }
}

@media (max-width: 760px) {
  .nav { min-height: 68px; }
  .nav-toggle {
    display: inline-flex;
    flex-direction: column;
    gap: 5px;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    border: 1px solid var(--border);
    border-radius: 14px;
    background: white;
    cursor: pointer;
  }
  .nav-toggle span { width: 20px; height: 2px; background: var(--text); transition: 0.2s ease; }
  .nav-toggle.is-open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .nav-toggle.is-open span:nth-child(2) { opacity: 0; }
  .nav-toggle.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
  .site-nav {
    position: fixed;
    inset: 68px 0 auto 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
    padding: 18px 4%;
    background: rgba(255,255,255,0.98);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow);
  }
  .site-nav.is-open { display: flex; }
  .site-nav a, .lang-toggle { text-align: left; padding: 13px 14px; }
  .cards.four, .cards.three { grid-template-columns: 1fr; }
  .actions .button { width: 100%; }
  .hero, .page-hero { padding-top: 48px; }
  .footer { display: grid; }
}

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