/* ===== RESET & BASE ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --color-bg: #fafafa;
  --color-surface: #ffffff;
  --color-border: #e8e8e8;
  --color-text: #1a1a1a;
  --color-text-muted: #6b7280;
  --color-accent: #2563eb;
  --color-accent-hover: #1d4ed8;
  --color-accent-light: #eff6ff;
  --color-success: #16a34a;
  --radius: 12px;
  --radius-sm: 8px;
  --shadow: 0 1px 3px rgba(0,0,0,.06), 0 4px 16px rgba(0,0,0,.04);
  --shadow-hover: 0 4px 12px rgba(0,0,0,.1), 0 8px 32px rgba(0,0,0,.06);
  --transition: 0.22s ease;
  --font: 'Inter', system-ui, -apple-system, sans-serif;
  --max-w: 1120px;
  --header-h: 68px;
}

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

img, svg { display: block; }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
ul { list-style: none; }

.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== BUTTONS ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 11px 22px;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 500;
  transition: background var(--transition), color var(--transition), box-shadow var(--transition), transform var(--transition);
  white-space: nowrap;
}
.btn:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 3px; }
.btn--primary {
  background: var(--color-accent);
  color: #fff;
}
.btn--primary:hover {
  background: var(--color-accent-hover);
  box-shadow: 0 4px 14px rgba(37,99,235,.3);
  transform: translateY(-1px);
}
.btn--ghost {
  background: transparent;
  color: var(--color-text);
  border: 1.5px solid var(--color-border);
}
.btn--ghost:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background: var(--color-accent-light);
}

/* ===== HEADER ===== */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(250,250,250,.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}
.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}
.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: 1rem;
  color: var(--color-text);
  transition: opacity var(--transition);
}
.logo:hover { opacity: 0.75; }
.logo__icon {
  color: var(--color-accent);
  font-size: 1.1rem;
  line-height: 1;
}
.nav {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
}
.nav__link {
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 450;
  color: var(--color-text-muted);
  transition: color var(--transition), background var(--transition);
}
.nav__link:hover { color: var(--color-text); background: var(--color-border); }
.nav__link--active { color: var(--color-accent); }
.nav__cta { margin-left: 12px; }
.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  border-radius: var(--radius-sm);
  margin-left: 8px;
}
.nav__toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}
.nav__toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav__toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav__toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ===== HERO ===== */
.hero {
  padding: 96px 0 80px;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}
.hero__inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}
.hero__badge {
  display: inline-block;
  padding: 4px 12px;
  background: var(--color-accent-light);
  color: var(--color-accent);
  border-radius: 100px;
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  margin-bottom: 20px;
}
.hero__heading {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
  color: var(--color-text);
}
.hero__sub {
  font-size: 1.05rem;
  color: var(--color-text-muted);
  max-width: 480px;
  margin-bottom: 32px;
  line-height: 1.7;
}
.hero__actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}
.hero__trust {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  gap: 6px;
}
.hero__trust::before {
  content: '';
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-success);
  flex-shrink: 0;
}
.hero__visual {
  display: flex;
  justify-content: center;
  align-items: center;
}
.hero__card {
  width: 100%;
  max-width: 340px;
  aspect-ratio: 16/10;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 28px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 14px;
  box-shadow: var(--shadow);
}
.hero__card-line {
  height: 10px;
  background: var(--color-border);
  border-radius: 100px;
  width: 80%;
}
.hero__card-line--short { width: 55%; }
.hero__card-dots {
  display: flex;
  gap: 8px;
  margin-top: 8px;
}
.hero__card-dots span {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--color-border);
}
.hero__card-dots span:first-child { background: var(--color-accent-light); }

/* ===== SECTION HEADER ===== */
.section-header {
  text-align: center;
  margin-bottom: 56px;
}
.section-header h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}
.section-header p {
  font-size: 1rem;
  color: var(--color-text-muted);
  max-width: 520px;
  margin: 0 auto;
}

/* ===== WHY SECTION ===== */
.why {
  padding: 96px 0;
  background: var(--color-bg);
}
.cards-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 28px 24px;
  transition: box-shadow var(--transition), transform var(--transition);
}
.card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}
.card__icon {
  width: 44px;
  height: 44px;
  background: var(--color-accent-light);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-accent);
  margin-bottom: 16px;
}
.card h3 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 8px;
}
.card p {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  line-height: 1.65;
}

/* ===== DONATE SECTION ===== */
.donate {
  padding: 96px 0;
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
}
.donate__group { margin-bottom: 56px; }
.donate__group:last-child { margin-bottom: 0; }
.donate__group-title {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 24px;
  color: var(--color-text);
}
.donate__group-icon {
  width: 36px;
  height: 36px;
  background: var(--color-accent-light);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-accent);
  flex-shrink: 0;
}

/* Crypto Cards */
.crypto-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}
.crypto-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  transition: box-shadow var(--transition), transform var(--transition);
}
.crypto-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}
.crypto-card__header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 20px;
}
.crypto-card__icon {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  font-weight: 700;
  flex-shrink: 0;
}
.crypto-card__icon--btc { background: #fff7ed; color: #ea580c; }
.crypto-card__icon--eth { background: #f5f3ff; color: #7c3aed; }
.crypto-card__icon--usdt { background: #f0fdf4; color: #16a34a; }
.crypto-card__icon--ltc { background: #f0f9ff; color: #0284c7; }
.crypto-card__name {
  font-weight: 600;
  font-size: 0.95rem;
}
.crypto-card__ticker {
  font-size: 0.78rem;
  color: var(--color-text-muted);
  font-weight: 500;
  margin-top: 2px;
}
.crypto-card__label {
  display: block;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 8px;
}
.crypto-card__address-row {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 10px 12px;
}
.crypto-card__address {
  font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
  font-size: 0.78rem;
  color: var(--color-text);
  word-break: break-all;
  flex: 1;
  line-height: 1.5;
}
.copy-btn {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 6px 10px;
  background: var(--color-accent-light);
  color: var(--color-accent);
  border-radius: 6px;
  font-size: 0.78rem;
  font-weight: 500;
  white-space: nowrap;
  flex-shrink: 0;
  transition: background var(--transition), color var(--transition);
}
.copy-btn:hover { background: var(--color-accent); color: #fff; }
.copy-btn:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }
.copy-btn.copied { background: #dcfce7; color: var(--color-success); }

/* Gateway Cards */
.gateway-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}
.gateway-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 32px 28px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition: box-shadow var(--transition), transform var(--transition);
}
.gateway-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}
.gateway-card__icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
}
.gateway-card__icon--razorpay { background: #fef3c7; color: #d97706; }
.gateway-card__icon--paypal { background: #eff6ff; color: #1d4ed8; }
.gateway-card h4 {
  font-size: 1.05rem;
  font-weight: 600;
}
.gateway-card p {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  line-height: 1.65;
  flex: 1;
}
.gateway-card__btn { margin-top: 8px; align-self: flex-start; }

/* ===== TRANSPARENCY ===== */
.transparency {
  padding: 96px 0;
  background: var(--color-bg);
  border-top: 1px solid var(--color-border);
}
.transparency__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 40px;
}
.transparency__item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  transition: box-shadow var(--transition);
}
.transparency__item:hover { box-shadow: var(--shadow-hover); }
.transparency__icon {
  width: 40px;
  height: 40px;
  background: var(--color-accent-light);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-accent);
  flex-shrink: 0;
}
.transparency__item h4 {
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 4px;
}
.transparency__item p {
  font-size: 0.83rem;
  color: var(--color-text-muted);
  line-height: 1.6;
}
.transparency__note {
  text-align: center;
  font-size: 0.9rem;
  color: var(--color-text-muted);
  max-width: 560px;
  margin: 0 auto;
  padding: 20px 24px;
  background: var(--color-accent-light);
  border-radius: var(--radius);
  border: 1px solid #bfdbfe;
  color: #1e40af;
}

/* ===== FAQ ===== */
.faq {
  padding: 96px 0;
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
}
.faq__list {
  max-width: 720px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.faq__item {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--color-bg);
}
.faq__question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 20px 24px;
  font-size: 0.95rem;
  font-weight: 500;
  text-align: left;
  color: var(--color-text);
  transition: background var(--transition);
}
.faq__question:hover { background: var(--color-border); }
.faq__question:focus-visible { outline: 2px solid var(--color-accent); outline-offset: -2px; }
.faq__chevron {
  flex-shrink: 0;
  transition: transform var(--transition);
  color: var(--color-text-muted);
}
.faq__question[aria-expanded="true"] .faq__chevron { transform: rotate(180deg); }
.faq__answer {
  padding: 0 24px 20px;
  font-size: 0.875rem;
  color: var(--color-text-muted);
  line-height: 1.7;
  animation: fadeIn 0.2s ease;
}
.faq__answer[hidden] { display: none; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(-4px); } to { opacity: 1; transform: translateY(0); } }

/* ===== FOOTER ===== */
.footer {
  background: var(--color-text);
  color: #d1d5db;
  border-top: 1px solid var(--color-border);
}
.footer__inner {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 40px;
  padding-top: 56px;
  padding-bottom: 40px;
}
.footer .logo { color: #fff; }
.footer .logo__icon { color: #93c5fd; }
.footer__tagline {
  font-size: 0.83rem;
  color: #9ca3af;
  margin-top: 6px;
}
.footer__built {
  font-size: 0.8rem;
  color: #6b7280;
  margin-top: 4px;
}
.footer__nav {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
  align-items: center;
  padding-top: 4px;
}
.footer__nav a {
  font-size: 0.875rem;
  color: #9ca3af;
  transition: color var(--transition);
}
.footer__nav a:hover { color: #fff; }
.footer__bottom {
  border-top: 1px solid #374151;
  padding: 16px 0;
}
.footer__bottom p {
  font-size: 0.8rem;
  color: #6b7280;
  text-align: center;
}

/* ===== TOAST ===== */
.toast {
  position: fixed;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%) translateY(80px);
  background: #1a1a1a;
  color: #fff;
  padding: 12px 20px;
  border-radius: 100px;
  font-size: 0.875rem;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 8px;
  z-index: 9999;
  opacity: 0;
  transition: transform 0.3s cubic-bezier(.34,1.56,.64,1), opacity 0.3s ease;
  pointer-events: none;
  white-space: nowrap;
}
.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}
.toast svg { color: #4ade80; }

/* ===== REVEAL ANIMATIONS ===== */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal--delay { transition-delay: 0.15s; }

/* ===== RESPONSIVE ===== */
@media (max-width: 1024px) {
  .cards-grid { grid-template-columns: repeat(2, 1fr); }
  .transparency__grid { grid-template-columns: repeat(2, 1fr); }
  .hero__inner { gap: 40px; }
}

@media (max-width: 768px) {
  :root { --header-h: 60px; }

  .nav__list, .nav__cta { display: none; }
  .nav__toggle { display: flex; }
  .nav__list.open {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    padding: 16px 24px 24px;
    gap: 4px;
    z-index: 99;
    box-shadow: 0 8px 24px rgba(0,0,0,.08);
  }
  .nav__list.open + .nav__cta {
    display: flex;
    margin: 0 24px 16px;
    position: fixed;
    top: calc(var(--header-h) + 16px + 5 * 44px);
    left: 0;
    right: 0;
    z-index: 99;
    justify-content: center;
  }

  .hero { padding: 64px 0 56px; }
  .hero__inner { grid-template-columns: 1fr; gap: 40px; }
  .hero__visual { display: none; }
  .hero__heading { font-size: 2rem; }

  .why, .donate, .transparency, .faq { padding: 64px 0; }

  .cards-grid { grid-template-columns: 1fr; }
  .crypto-grid { grid-template-columns: 1fr; }
  .gateway-grid { grid-template-columns: 1fr; }
  .transparency__grid { grid-template-columns: 1fr; }

  .footer__inner { flex-direction: column; gap: 24px; padding-top: 40px; padding-bottom: 32px; }
  .footer__nav { gap: 16px; }
}

@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .hero__actions { flex-direction: column; }
  .hero__actions .btn { width: 100%; justify-content: center; }
  .crypto-card__address-row { flex-direction: column; align-items: flex-start; }
  .copy-btn { width: 100%; justify-content: center; }
  .gateway-card__btn { width: 100%; justify-content: center; }
  .section-header { margin-bottom: 36px; }
}