:root {
  /* Brand tokens (dark, low-carbon) */
  color-scheme: dark;
  --bg: #0d0d0d;
  --fg: #fafafa;
  --muted: #d1d5db;

  /* Accents */
  --accent-payment: #1e90ff; /* bold */
  --accent-social:  #60a5fa; /* soft */

  /* Interaction + surface */
  --ring: #93c5fd;
  --border: #1f2937;
  --radius: 1rem;
  --shadow: 0 6px 16px rgba(0, 0, 0, 0.3);
}

* { box-sizing: border-box; }

html, body { height: 100%; }

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  background: var(--bg);
  color: var(--fg);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
  Roboto, Oxygen, Ubuntu, Cantarell, "Open Sans",
  "Helvetica Neue", sans-serif;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

main {
  width: min(92vw, 700px);
  text-align: center;
  padding: 2rem 2.25rem;
  border: 2px solid var(--accent-payment);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  background: linear-gradient(180deg, #0f0f10, #0b0b0b);
}

h1, h2 {
  font-size: 1.75rem;
  margin-bottom: 1rem;
  letter-spacing: 0.03em;
  font-weight: 700;
  text-wrap: balance;
}

h2 {
  font-size: 1.35rem;
  margin-top: 2.25rem;
  font-weight: 600;
}

.tagline {
  font-size: 1rem;
  color: var(--muted);
  margin-bottom: 1.5rem;
  font-style: italic;
}

/* Lists */
ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 1rem;
}

/* DRY tokens for link blocks */
.payment-links { --accent: var(--accent-payment); }
.social-links  { --accent: var(--accent-social);  }

/* Link blocks */
.payment-links a,
.social-links a {
  --bgc: var(--accent);
  --bdr: #ffffff33;

  display: flex;
  align-items: center;
  justify-content: center;

  min-height: 44px; /* touch target */
  padding: .75rem 1.5rem;
  background: var(--bgc);
  color: var(--bg);
  border: 1px solid var(--bdr);
  border-radius: .5rem;
  font-weight: 600;
  text-decoration: none;

  transition: transform .18s ease, opacity .18s ease, background-color .18s ease, box-shadow .18s ease;
}

/* Slightly gentler default for social */
.social-links a {
  padding: .6rem 1.25rem;
  font-size: 1rem;
}

/* Hover/Focus (use color-mix if available; graceful fallback) */
.payment-links a:hover,
.payment-links a:focus-visible,
.social-links a:hover,
.social-links a:focus-visible {
  transform: translateY(-3px) scale(1.03);
  opacity: .97;
  /* Progressive enhancement */
  background: color-mix(in oklab, var(--accent) 92%, white 8%);
  box-shadow: 0 0 0 3px color-mix(in oklab, var(--ring) 35%, transparent 65%);
}

a:active {
  transform: translateY(0) scale(1);
  opacity: 1;
}

/* Robust focus for keyboard users */
a:focus-visible {
  outline: 2px solid var(--ring);
  outline-offset: 3px;
}

/* Skip link support (present if added to DOM) */
.skip {
  position: absolute;
  left: -9999px;
}
.skip:focus {
  left: 1rem;
  top: 1rem;
  background: var(--ring);
  color: #06121f;
  padding: .5rem .75rem;
  border-radius: .5rem;
  z-index: 999;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
  a:hover, a:focus-visible { transform: none !important; }
}

/* Higher contrast users */
@media (prefers-contrast: more) {
  main { border-width: 3px; }
  a:focus-visible { outline-width: 3px; }
}

/* Forced-colors (Windows High Contrast) */
@media (forced-colors: active) {
  main { border-color: CanvasText; }
  a { forced-color-adjust: auto; }
}

/* Small screens */
@media (max-width: 480px) {
  main { padding: 1.25rem 1.5rem; }
  h1, h2 { font-size: 1.35rem; }
  h2 { font-size: 1.1rem; margin-top: 1.5rem; }
  .tagline { font-size: .95rem; margin-bottom: 1rem; }
  .payment-links a { padding: .6rem 1.25rem; font-size: 1rem; }
  .social-links a  { padding: .5rem 1rem; font-size: .9rem; }
}

/* Optional utility for tiny notes */
.note { color: var(--muted); font-size: .95rem; }