:root{
  --bg: #0b1020;
  --fg: #e7ebf5;
  --muted: #a9b4c8;
  --glass: rgba(255,255,255,0.14);
  --stroke: rgba(255,255,255,.28);
  --btn: #1b2a3a;
  --btn-text: #eaf4ff;
  --accent: #66e0e0;
}

*,
*::before,
*::after { box-sizing: border-box; }

html, body { height: 100%; }

body {
  margin: 0;
  padding: 0;
  color: var(--fg);
  background-color: var(--bg);
  /* navy crosshatch background */
  background-image:
    repeating-linear-gradient(45deg, rgba(255,255,255,.08) 0 2px, transparent 2px 8px),
    repeating-linear-gradient(-45deg, rgba(255,255,255,.08) 0 2px, transparent 2px 8px);
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto;
  line-height: 1.5;
}

main {
  display: grid;
  place-items: center;
  padding: 2rem 1rem;
  min-height: 60vh;
}

.image-frame {
  position: relative;
  width: min(92vw, 1000px);
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border-radius: 14px;
  border: 1px solid rgba(255,255,255,.25);
  background: #000;
  box-shadow: 0 12px 40px rgba(0,0,0,.45);
}
.image-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  filter: saturate(1.05) contrast(1.05);
}
.image-frame::after {
  content: "";
  position: absolute; inset: 0;
  /* subtle frosted-glass overlay to emphasize hacker vibe */
  background: linear-gradient(to bottom, rgba(255,255,255,.16), rgba(255,255,255,.04) 60%, rgba(255,255,255,0) 100%);
  mix-blend-mode: overlay;
  pointer-events: none;
  backdrop-filter: blur(0.5px);
}

/* Optional caption overlay (not required by HTML) */
/* .hero-caption { position: absolute; bottom: 12px; left: 12px; right: 12px; } */

footer {
  width: 100%;
  padding: 1.5rem 0;
  color: var(--fg);
  display: grid;
  place-items: center;
}

.product-ad {
  width: min(92%, 720px);
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 1rem;
  padding: 0.9rem 1rem;
  border-radius: 12px;
  background: rgba(255,255,255,.08);
  border: 1px solid rgba(255,255,255,.25);
  text-align: left;
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
}
.product-ad h3 {
  margin: 0;
  font-size: 1rem;
  color: var(--fg);
  letter-spacing: .2px;
}
.product-ad p { margin: 0; }

.product-ad a {
  display: inline-block;
  padding: 0.75rem 1.25rem;
  border-radius: 999px;
  text-decoration: none;
  color: #061522;
  font-weight: 700;
  background: linear-gradient(135deg, #cde6ff 0%, #9bb9d6 100%);
  border: 1px solid rgba(255,255,255,.95);
  transition: transform .2s ease;
}
.product-ad a:hover { transform: translateY(-1px); }
.product-ad a:focus-visible {
  outline: 2px solid #6bd3ff;
  outline-offset: 2px;
}

footer p {
  text-align: center;
  margin: 0.75rem 0 0;
  color: var(--muted);
  font-size: .9rem;
}

/* Accessibility: ensure focus visibility on interactive elements */
a:focus, button:focus, input:focus {
  outline: 2px solid #6bd3ff;
  outline-offset: 2px;
  border-radius: 6px;
}

/* Mobile-first responsive tweaks */
@media (min-width: 600px) {
  main { padding: 3rem 2rem; min-height: 70vh; }
  .image-frame { width: min(860px, 85%); border-radius: 16px; }
  .product-ad { grid-template-columns: 1fr auto; }
}
@media (min-width: 900px) {
  main { padding: 4rem 2rem; }
  .image-frame { width: min(1000px, 80%); }
  .product-ad { padding: 1rem 1.2rem; }
}