:root {
    --gap: 12px;
  }
  * { box-sizing: border-box; }
  body { font-family: system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, sans-serif; margin: 0; }
  .wrapper { min-height: 100svh; display: grid; grid-template-rows: auto 1fr auto; }
  .header { padding: 16px; text-align: center; }
  .grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--gap);
    padding: var(--gap);
    max-width: 1100px;
    margin: 0 auto;
  }
  .tile {
    display: grid; place-items: center;
    aspect-ratio: 1 / 1;
    border-radius: 18px;
    text-decoration: none;
    color: #fff;
    font-weight: 600;
    font-size: 1.2rem;
    box-shadow: 0 8px 20px rgba(0,0,0,0.15);
    transition: transform .12s ease, box-shadow .12s ease, opacity .2s ease;
  }
  .tile:hover { transform: translateY(-2px); box-shadow: 0 12px 24px rgba(0,0,0,0.2); }
  .tile small { display:block; opacity:.85; font-weight:500; font-size:.85rem; }
  .footer { padding: 12px 16px; text-align: center; opacity: .7; }
  .footer a { color: inherit; text-decoration: underline; }
  @media (max-width: 920px) {
    .grid { grid-template-columns: repeat(3, 1fr); }
  }
  @media (max-width: 640px) {
    .grid { grid-template-columns: repeat(2, 1fr); }
  }