:root {
  --bg: #10131a;
  --surface: #171b23;
  --surface-2: #1f2430;
  --text: #e4e9f2;
  --muted: #a5b0c2;
  --primary: #b8c4ff;
  --primary-strong: #8da2ff;
  --outline: #343c4d;
  --shadow: 0 10px 25px rgba(0, 0, 0, 0.28);
}

:root[data-theme='light'] {
  --bg: #f5f7fd;
  --surface: #ffffff;
  --surface-2: #edf1fb;
  --text: #171c2a;
  --muted: #505b72;
  --primary: #465cbe;
  --primary-strong: #30479f;
  --outline: #d6dcec;
  --shadow: 0 10px 24px rgba(32, 52, 102, 0.14);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: Inter, system-ui, -apple-system, Segoe UI, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
  transition: background-color .25s ease, color .2s ease;
}

.container { width: min(1120px, 92vw); margin-inline: auto; }
a { color: inherit; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: color-mix(in oklab, var(--bg) 80%, transparent);
  border-bottom: 1px solid var(--outline);
  backdrop-filter: blur(10px);
}

.nav-wrap {
  display: grid;
  grid-template-columns: auto 1fr auto auto;
  align-items: center;
  gap: .8rem;
  padding: .8rem 0;
}

.logo {
  text-decoration: none;
  font-weight: 700;
  display: inline-flex;
  align-items: center;
  gap: .5rem;
}

.logo-mark {
  width: 2rem;
  height: 2rem;
  display: grid;
  place-items: center;
  border-radius: .7rem;
  background: var(--surface-2);
  border: 1px solid var(--outline);
}

.primary-nav {
  justify-self: end;
  display: flex;
  align-items: center;
  gap: .3rem;
}

.primary-nav a,
.footer-nav a {
  text-decoration: none;
  padding: .55rem .85rem;
  border-radius: 999px;
  color: var(--muted);
}

.primary-nav a:hover,
.footer-nav a:hover {
  color: var(--text);
  background: var(--surface-2);
}

.icon-button {
  border: 1px solid var(--outline);
  background: var(--surface);
  color: var(--text);
  width: 2.45rem;
  height: 2.45rem;
  border-radius: .8rem;
  cursor: pointer;
}

.menu-toggle { display: none; }

.hero { padding: 5rem 0 2rem; text-align: center; }
.hero h1 { font-size: clamp(1.8rem, 4vw, 3rem); margin-bottom: .6rem; }
.hero p { color: var(--muted); max-width: 68ch; margin: 0 auto 1.5rem; }

.button {
  display: inline-block;
  padding: .82rem 1.2rem;
  border-radius: .9rem;
  text-decoration: none;
  font-weight: 700;
  color: #f9fbff;
  background: linear-gradient(135deg, var(--primary), var(--primary-strong));
  box-shadow: var(--shadow);
}

h2 { margin: 1rem 0; }
.page-head { padding-top: 2rem; }
.page-head p { color: var(--muted); }

.toolbar {
  display: grid;
  gap: .9rem;
  margin: 1.1rem auto 2rem;
  background: var(--surface);
  border: 1px solid var(--outline);
  border-radius: 1rem;
  padding: 1rem;
}

input[type='search'] {
  width: 100%;
  padding: .85rem 1rem;
  border-radius: .8rem;
  border: 1px solid var(--outline);
  background: var(--surface-2);
  color: var(--text);
}

.filters { display: flex; gap: .55rem; flex-wrap: wrap; }
.filters button,
.controls button {
  border: 1px solid var(--outline);
  background: var(--surface-2);
  color: var(--text);
  padding: .45rem .75rem;
  border-radius: .7rem;
  cursor: pointer;
}

.filters .active {
  border-color: transparent;
  background: linear-gradient(135deg, var(--primary), var(--primary-strong));
  color: #f9fbff;
}

.game-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1rem;
  margin-bottom: 2rem;
}

.game-card {
  background: var(--surface);
  border: 1px solid var(--outline);
  border-radius: 1rem;
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: transform .18s ease, box-shadow .2s ease;
}

.game-card:hover { transform: translateY(-3px); }
.game-card img { width: 100%; aspect-ratio: 16/9; object-fit: cover; background: var(--surface-2); }
.game-card a { color: inherit; text-decoration: none; }
.game-card h2, .game-card h3 { margin: .8rem .9rem .35rem; }
.game-card p { margin: 0 .9rem 1rem; color: var(--muted); font-size: .93rem; }

.game-shell { padding-bottom: 3rem; }
.game-surface,
.faq details {
  background: var(--surface);
  border: 1px solid var(--outline);
  border-radius: 1rem;
}

.game-surface { padding: 1rem; overflow-x: auto; }
canvas {
  width: min(100%, 720px);
  max-width: 100%;
  height: auto;
  background: #090b14;
  border-radius: .75rem;
  display: block;
  margin: auto;
  touch-action: none;
}

.controls { display: flex; gap: .5rem; flex-wrap: wrap; justify-content: center; margin-top: 1rem; }
.badge-row span {
  display: inline-block;
  margin-right: .45rem;
  background: var(--surface-2);
  border: 1px solid var(--outline);
  padding: .25rem .5rem;
  border-radius: 999px;
  font-size: .78rem;
}

.faq details { padding: .8rem .9rem; margin: .65rem 0; }
.hidden { display: none !important; }

.site-footer {
  margin-top: 3rem;
  border-top: 1px solid var(--outline);
  background: var(--surface);
}

.footer-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.1rem 0 .8rem;
}

.footer-title { font-weight: 700; margin: 0; }
.footer-copy, .footer-meta { color: var(--muted); }
.footer-copy { margin: .25rem 0 0; }
.footer-meta { border-top: 1px solid var(--outline); padding: .7rem 0 1.1rem; font-size: .9rem; }

#sudokuGrid { display: grid; grid-template-columns: repeat(9, minmax(30px, 1fr)); gap: 4px; max-width: 520px; margin: 0 auto; }
.sudoku-cell { aspect-ratio: 1/1; text-align: center; font-size: 1.1rem; background: var(--surface-2); color: var(--text); border: 1px solid var(--outline); border-radius: 4px; }
.sudoku-cell:disabled { background: color-mix(in oklab, var(--surface-2) 70%, var(--primary)); font-weight: 700; }

@media (max-width: 840px) {
  .nav-wrap { grid-template-columns: auto auto auto; }
  .menu-toggle { display: inline-grid; place-items: center; }
  .primary-nav {
    position: absolute;
    left: 4vw;
    right: 4vw;
    top: calc(100% + .5rem);
    padding: .6rem;
    border-radius: .9rem;
    border: 1px solid var(--outline);
    background: var(--surface);
    display: none;
    flex-direction: column;
    align-items: stretch;
    box-shadow: var(--shadow);
  }
  .primary-nav.open { display: flex; }
  .primary-nav a { text-align: center; }
  .footer-wrap { flex-direction: column; align-items: flex-start; }
  .hero { padding-top: 3.5rem; }
}