:root {
  color-scheme: dark;
  --bg: #07101f;
  --surface: #101d32;
  --surface-high: #172742;
  --line: #2b3d59;
  --text: #f5f8ff;
  --muted: #a9b7cd;
  --cyan: #58d7ec;
  --cyan-dark: #163e55;
  --violet: #b8a7ff;
  --violet-dark: #352e65;
  --danger: #ff7185;
  --gold: #ffcf66;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { min-width: 280px; background: var(--bg); }
body {
  min-height: 100vh;
  min-height: 100dvh;
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(circle at 12% 8%, rgba(38, 109, 145, 0.22), transparent 28rem),
    radial-gradient(circle at 92% 30%, rgba(91, 62, 150, 0.16), transparent 28rem),
    var(--bg);
}
button { font: inherit; }
button:focus-visible { outline: 3px solid var(--gold); outline-offset: 3px; }

.app-shell { width: min(100% - 24px, 1040px); margin: 0 auto; padding: 30px 0 48px; }
.site-header { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 24px; }
h1, h2, p { margin-top: 0; }
h1 { margin-bottom: 0; font-size: clamp(2rem, 6vw, 3.2rem); letter-spacing: -0.055em; line-height: 1; }
h1 span { color: var(--cyan); }
h2 { margin-bottom: 0; font-size: 1.35rem; }
.eyebrow, .section-label { margin-bottom: 7px; color: var(--muted); font-size: 0.72rem; font-weight: 800; letter-spacing: 0.12em; text-transform: uppercase; }
.game-layout { display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 20px; align-items: start; }
.main-column, .side-column { display: grid; gap: 16px; }
.card { border: 1px solid var(--line); border-radius: 20px; background: rgba(16, 29, 50, 0.92); box-shadow: 0 18px 55px rgba(0, 0, 0, 0.18); }
.game-status { min-height: 92px; padding: 18px 22px; display: flex; align-items: center; gap: 16px; }
.cpu-card { padding: 20px; }
.cpu-selector { margin: 14px 0 0; padding: 0; border: 0; display: flex; gap: 8px; }
.cpu-selector label { position: relative; cursor: pointer; }
.cpu-selector input { position: absolute; opacity: 0; pointer-events: none; }
.cpu-selector span { min-height: 44px; padding: 9px 13px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 12px; color: var(--muted); background: var(--surface-high); font-weight: 800; }
.cpu-selector input:checked + span { border-color: var(--violet); color: var(--text); background: var(--violet-dark); }
.cpu-selector input:focus-visible + span { outline: 3px solid var(--gold); outline-offset: 3px; }
.cpu-selector input:disabled + span { cursor: not-allowed; opacity: 0.65; }
.score-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; }
.score-card { padding: 14px 18px; display: flex; align-items: center; gap: 14px; }
.score-card > div { min-width: 0; }
.score-card small { display: block; margin-bottom: 2px; color: var(--muted); font-weight: 700; }
.score-card strong { font-size: 1.7rem; }
.player-mark { width: 36px; height: 36px; display: grid; place-items: center; border-radius: 11px; font-weight: 900; }
.score-player .player-mark { color: #07101f; background: var(--cyan); }
.score-cpu .player-mark { color: #160d35; background: var(--violet); }
.score-mines .player-mark { color: #2e2104; background: var(--gold); }
.board-card { padding: clamp(10px, 3vw, 20px); }
.board {
  width: min(100%, max(284px, calc(100vh - 450px)));
  width: min(100%, max(284px, calc(100dvh - 450px)));
  margin-inline: auto;
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: clamp(4px, 1.3vw, 8px);
}
.cell {
  position: relative;
  aspect-ratio: 1;
  min-width: 0;
  border: 1px solid #405572;
  border-radius: clamp(8px, 2vw, 13px);
  color: var(--text);
  background: linear-gradient(145deg, #233652, #172841);
  box-shadow: inset 0 1px rgba(255, 255, 255, 0.07), 0 4px 10px rgba(0, 0, 0, 0.18);
  font-size: clamp(0.95rem, 4vw, 1.45rem);
  font-weight: 900;
  cursor: pointer;
  transition: transform 140ms ease, border-color 140ms ease, background 140ms ease;
}
.cell:not(:disabled):hover { transform: translateY(-2px); border-color: var(--cyan); }
.cell:disabled { cursor: default; opacity: 1; }
.cell-player { border: 2px solid var(--cyan); color: #bdf5ff; background: var(--cyan-dark); }
.cell-player::after { content: "P"; position: absolute; right: 6px; bottom: 3px; color: var(--cyan); font-size: 0.52rem; }
.cell-cpu { border: 2px dashed var(--violet); color: var(--violet); background: var(--violet-dark); }
.cell-cpu::after { content: "C"; font-size: 0.72rem; }
.cell-last-cpu { border: 3px solid var(--gold); background: #59431a; box-shadow: 0 0 0 3px rgba(255, 207, 102, 0.24), inset 0 1px rgba(255, 255, 255, 0.12); }
.cell-last-cpu::before { content: "★"; position: absolute; left: 4px; top: 2px; color: var(--gold); font-size: 0.66rem; line-height: 1; }
.cell-finished-safe::after { position: absolute; right: 5px; bottom: 2px; font-size: 0.48rem; }
.cell-mine { border: 2px solid var(--danger); color: #fff; background: #79293a; }
.cell-zero { color: #90a0b7; }
.legend { display: flex; flex-wrap: wrap; justify-content: center; gap: 16px; margin-top: 15px; color: var(--muted); font-size: 0.75rem; }
.legend span { display: flex; align-items: center; gap: 6px; }
.legend i { width: 10px; height: 10px; border-radius: 3px; }
.legend-player { background: var(--cyan); }
.legend-cpu { background: var(--violet); }
.legend .legend-last { width: auto; height: auto; color: var(--gold); background: transparent; font-style: normal; line-height: 1; }
.legend-closed { background: #405572; }
.actions { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.button { min-height: 46px; padding: 11px 18px; border: 1px solid transparent; border-radius: 13px; color: var(--text); font-weight: 800; cursor: pointer; }
.button:disabled { cursor: not-allowed; opacity: 0.45; }
.button-primary { color: #06101e; background: var(--cyan); }
.button-primary:not(:disabled):hover { background: #8be9f8; }
.button-secondary, .button-quiet { border-color: var(--line); background: var(--surface-high); }
.button-secondary:hover, .button-quiet:hover { border-color: #516785; }
.button-quiet { min-height: 42px; }
.stats-card { padding: 0; overflow: hidden; }
.tip-card, .result-card { padding: 20px; }
.card-heading, .dialog-heading { display: flex; align-items: start; justify-content: space-between; gap: 16px; }
.card-heading > strong { color: var(--cyan); }
.stats-list, .result-details { margin: 18px 0 0; display: grid; gap: 9px; }
.stats-list div, .result-details div { display: flex; justify-content: space-between; padding-top: 9px; border-top: 1px solid var(--line); }
.stats-trigger { width: 100%; padding: 20px; border: 0; color: inherit; text-align: left; background: transparent; cursor: pointer; }
.stats-trigger:hover { background: rgba(255, 255, 255, 0.035); }
.stats-trigger:focus-visible { outline-offset: -4px; }
.stats-trigger .section-label { display: block; }
.stats-title { display: block; font-size: 1.35rem; font-weight: 800; }
.stats-trigger .stats-list > span { display: flex; justify-content: space-between; padding-top: 9px; border-top: 1px solid var(--line); }
.stats-trigger .stats-list > span > span { color: var(--muted); }
.stats-more { display: block; margin-top: 16px; color: var(--cyan); font-weight: 800; text-align: right; }
dt { color: var(--muted); }
dd { margin: 0; font-weight: 900; }
.tip-card p:last-child, .result-card > p { margin-bottom: 0; color: var(--muted); line-height: 1.7; }
.result-card { border-color: #456278; background: linear-gradient(145deg, #152b40, #171e38); }
.result-card .button { width: 100%; margin-top: 18px; }
.warning, .noscript { margin-bottom: 16px; padding: 12px 16px; border: 1px solid #9b713a; border-radius: 12px; color: #ffe1a2; background: #3d2b17; }
.dialog { width: min(calc(100% - 24px), 540px); max-height: calc(100dvh - 24px); overflow: auto; border: 1px solid var(--line); border-radius: 20px; padding: 0; color: var(--text); background: var(--surface); box-shadow: 0 30px 90px #000; }
.dialog::backdrop { background: rgba(2, 7, 16, 0.78); backdrop-filter: blur(4px); }
.dialog form { padding: 24px; }
.dialog ol { padding-left: 1.4rem; color: var(--muted); line-height: 1.7; }
.dialog li + li { margin-top: 9px; }
.dialog-close { width: 100%; margin-top: 6px; }
.stats-detail-list { margin-bottom: 22px; }
.stats-subheading { margin: 0; font-size: 1rem; }
.stats-mode-list { grid-template-columns: repeat(2, minmax(0, 1fr)); column-gap: 18px; }
.dialog-actions { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.button-danger { border-color: var(--danger); color: #fff; background: #652536; }
.button-danger:hover { background: #7c2d41; }
.icon-button { width: 44px; height: 44px; border: 1px solid var(--line); border-radius: 12px; color: var(--text); background: var(--surface-high); font-size: 1.4rem; cursor: pointer; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

@media (max-width: 780px) {
  .game-layout { grid-template-columns: 1fr; }
  .side-column { grid-template-columns: repeat(2, 1fr); }
  .result-card { grid-column: 1 / -1; }
}
@media (max-width: 520px) {
  .app-shell { width: min(100% - 20px, 1040px); padding-top: 20px; }
  .site-header { margin-bottom: 18px; }
  .eyebrow { display: none; }
  .game-status { padding: 15px 17px; }
  .cpu-selector label { flex: 1; }
  .score-grid { gap: 10px; }
  .score-card { padding: 10px 8px; gap: 6px; }
  .score-card small { font-size: 0.68rem; }
  .score-card strong { font-size: 1.4rem; }
  .player-mark { width: 28px; height: 28px; border-radius: 9px; font-size: 0.78rem; }
  .side-column { grid-template-columns: 1fr; }
  .dialog-actions { grid-template-columns: 1fr; }
}
@media (max-height: 1100px) {
  .app-shell { padding-top: 12px; padding-bottom: 18px; }
  .site-header { margin-bottom: 10px; }
  .eyebrow { display: none; }
  .main-column, .side-column { gap: 8px; }
  .game-status { min-height: 56px; padding: 8px 14px; }
  .score-grid { gap: 8px; }
  .score-card { padding: 7px 10px; gap: 8px; }
  .score-card strong { font-size: 1.4rem; }
  .player-mark { width: 28px; height: 28px; border-radius: 9px; font-size: 0.78rem; }
  .board-card { padding: 8px; }
  .board {
    width: min(100%, max(284px, calc(100vh - 320px)));
    width: min(100%, max(284px, calc(100dvh - 320px)));
  }
  .legend { gap: 6px 10px; margin-top: 8px; font-size: 0.68rem; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; }
}