:root {
  --bg: #0a0f17;
  --bg-2: #0b1420;
  --surface: rgba(2, 6, 23, 0.22);
  --text: #e9fbff;
  --muted: #b7d0e0;
  --accent: #ffd600;       /* cyber yellow */
  --accent-2: #2ee1c5;      /* seafoam */
  --shadow: 0 6px 18px rgba(0,0,0,.28);
  --radius: 14px;
  --focus: 0 0 0 3px rgba(46, 225, 197, 0.8);
}
* { box-sizing: border-box; }
html, body { height: 100%; }
html { font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "Liberation Sans", sans-serif; }
body {
  margin: 0;
  color: var(--text);
  background-color: var(--bg);
  /* Layered background: subtle gradient + checkerboard cyber-yellow accent + scanlines */
  background-image:
    linear-gradient(135deg, rgba(255, 214, 0, .12) 25%, transparent 25%),
    linear-gradient(-45deg, rgba(255, 214, 0, .12) 25%, transparent 25%),
    repeating-linear-gradient(to bottom, rgba(255,255,255,.035) 0 1px, transparent 1px 2px),
    linear-gradient(to bottom, rgba(0,0,0,.25), rgba(0,0,0,.5)),
    linear-gradient(#0a0f17, #0a0f17);
  background-size: 40px 40px, 40px 40px, 100% 2px, 100% 100%, 100% 100%;
  background-position: 0 0, 0 0, 0 0, 0 0, 0 0;
  background-blend-mode: overlay, overlay, normal, normal, normal;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
@supports (backdrop-filter: blur(8px)) or (-webkit-backdrop-filter: blur(8px)) {
  body { }
}
@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; }
}
html, body { height: 100%; }

/* Base layout helpers */
.container { width: 100%; max-width: clamp(320px, 92vw, 1100px); margin-inline: auto; padding: 1rem; }
.grid { display: grid; gap: 1rem; }
.card { border-radius: var(--radius); padding: 1rem; }
.tag { display: inline-block; padding: .25em .6em; font-size: .75rem; border-radius: 999px; border: 1px solid rgba(255,255,255,.25); color: var(--text); background: rgba(2,6,23,.25); }

/* Glass panels (frosted glass) with graceful fallback */
header, main, footer, aside, .image-frame, .product-ad, article {
  background: var(--surface);
  border: 1px solid rgba(255,255,255,.25);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backdrop-filter: blur(10px) saturate(1.1);
  -webkit-backdrop-filter: blur(10px) saturate(1.1);
}
@supports not (backdrop-filter: blur(10px)) {
  header, main, footer, aside, .image-frame, .product-ad, article {
    background: rgba(2,6,23,.28);
  }
}
header, main, footer { padding: 1rem; }

/* Typography */
h1, h2, h3 { margin: .2em 0 .4em; font-weight: 800; line-height: 1.1; color: var(--text); }
h1 { font-size: clamp(1.8rem, 4vw + 0.5rem, 3.25rem); letter-spacing: .2px; }
p { color: var(--muted); font-size: clamp(1rem, 0.5vw + 0.9rem, 1.125rem); line-height: 1.5; margin: .25em 0 1em; }

/* Links and interactive elements */
a { color: var(--accent-2); text-decoration: none; }
a:hover, a:focus { text-decoration: underline; outline: none; }
a:focus-visible { outline: none; box-shadow: var(--focus); outline-offset: 4px; border-radius: 6px; }

/* Buttons and CTAs */
button, .btn, a.btn, .cta {
  font: inherit;
  cursor: pointer;
  border: 0;
  border-radius: 999px;
  padding: .8em 1.2em;
  transition: transform .2s ease, background .2s ease, border-color .2s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: #0b1117;
  text-decoration: none;
}
.btn { background: rgba(255,255,255,.08); color: var(--text); border: 1px solid rgba(255,255,255,.25); }
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }
.btn.primary { background: linear-gradient(135deg, var(--accent), #ffd000); color: #1b1a0b; font-weight: 700; border: 0; }
.btn.outline { background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.35); color: var(--text); }
.btn:focus-visible { outline: none; box-shadow: var(--focus); outline-offset: 2px; }

/* Image frame styling */
.image-frame { aspect-ratio: 16/9; width: 100%; overflow: hidden; border: 1px solid rgba(255,255,255,.28); border-radius: 12px; background: #111; display: block; }
.image-frame img { width: 100%; height: 100%; object-fit: cover; display: block; }

/* Content block and layout helpers */
.content { padding: 1rem; }
.product-ad { display: block; padding: .75rem 1rem; text-align: center; margin: .5rem 0; text-decoration: none; }
.product-ad a { text-decoration: none; color: var(--text); }
.sponsored-page { text-align: center; }

/* Layout structure (selectors required) */
html, body, header, nav, main, article, footer, aside { min-height: 0; }
nav { display: flex; gap: .75rem; align-items: center; }

/* Utility containers */
.container.narrow { max-width: 720px; }
.container.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }

/* Structural page elements (explicit selectors) */
header { display: block; margin: 0 auto 1rem; padding: 1.25rem; }
main { padding: 1rem; }
footer { padding: 1rem; margin-top: 1rem; }

/* Print styles (readable) */
@media print {
  body { background: #fff; color: #000; }
  a { text-decoration: underline; color: #00f; }
}
```