:root {
  color-scheme: light;
  --ink: #17130f;
  --muted: #6b6258;
  --paper: #f6f1e8;
  --board: #d7ad68;
  --board-dark: #8f6430;
  --panel: #fffaf1;
  --accent: #16615a;
  --accent-dark: #0f4540;
  --danger: #a23928;
  --shadow: 0 22px 60px rgba(37, 28, 16, 0.18);
  --cell-size: clamp(19px, 5.25vw, 38px);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    linear-gradient(90deg, rgba(23, 19, 15, 0.04) 1px, transparent 1px),
    linear-gradient(#faf7ef, var(--paper));
  background-size: 44px 44px, auto;
  color: var(--ink);
}

button {
  font: inherit;
}

.app-shell {
  min-height: 100vh;
  padding: clamp(18px, 4vw, 42px);
}

.game-surface {
  width: min(1180px, 100%);
  margin: 0 auto;
}

.game-copy {
  display: grid;
  gap: 10px;
  margin-bottom: clamp(18px, 3vw, 30px);
}

.eyebrow,
.label {
  margin: 0;
  color: var(--accent-dark);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1 {
  max-width: 760px;
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(2.2rem, 5vw, 4.9rem);
  font-weight: 700;
  line-height: 0.96;
  letter-spacing: 0;
}

.summary {
  max-width: 650px;
  margin: 0;
  color: var(--muted);
  font-size: clamp(1rem, 2vw, 1.18rem);
  line-height: 1.55;
}

.game-layout {
  display: grid;
  grid-template-columns: minmax(290px, max-content) minmax(260px, 340px);
  align-items: start;
  gap: clamp(18px, 4vw, 34px);
}

.board-wrap {
  width: calc(var(--cell-size) * 15);
  max-width: 100%;
  padding: clamp(10px, 2vw, 16px);
  border: 1px solid rgba(70, 45, 19, 0.36);
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.24), transparent 42%),
    var(--board);
  box-shadow: var(--shadow);
}

.board {
  display: grid;
  grid-template-columns: repeat(15, var(--cell-size));
  grid-template-rows: repeat(15, var(--cell-size));
  position: relative;
  width: calc(var(--cell-size) * 15);
  height: calc(var(--cell-size) * 15);
  border: 2px solid var(--board-dark);
  background:
    linear-gradient(var(--board-dark) 1px, transparent 1px),
    linear-gradient(90deg, var(--board-dark) 1px, transparent 1px),
    repeating-linear-gradient(
      35deg,
      rgba(111, 72, 28, 0.16),
      rgba(111, 72, 28, 0.16) 3px,
      rgba(255, 255, 255, 0.09) 3px,
      rgba(255, 255, 255, 0.09) 10px
    );
  background-size: var(--cell-size) var(--cell-size), var(--cell-size) var(--cell-size), auto;
}

.cell {
  display: grid;
  place-items: center;
  width: var(--cell-size);
  height: var(--cell-size);
  border: 0;
  border-radius: 0;
  background: transparent;
  padding: 0;
  cursor: pointer;
}

.cell:disabled {
  cursor: default;
}

.cell:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: -3px;
}

.cell:not(:disabled):hover {
  background: rgba(22, 97, 90, 0.15);
}

.stone {
  display: block;
  width: 76%;
  height: 76%;
  border-radius: 999px;
  box-shadow: inset -4px -5px 8px rgba(0, 0, 0, 0.28), 0 3px 8px rgba(0, 0, 0, 0.28);
}

.stone.black {
  background: radial-gradient(circle at 35% 30%, #5b554d 0 8%, #17130f 42%, #030303 100%);
}

.stone.white {
  border: 1px solid rgba(45, 38, 29, 0.28);
  background: radial-gradient(circle at 35% 30%, #ffffff 0 16%, #eee8dd 58%, #cfc5b6 100%);
}

.stone.is-last {
  box-shadow:
    0 0 0 3px rgba(22, 97, 90, 0.72),
    inset -4px -5px 8px rgba(0, 0, 0, 0.22),
    0 3px 8px rgba(0, 0, 0, 0.24);
}

.panel {
  display: grid;
  gap: 16px;
  padding: 20px;
  border: 1px solid rgba(70, 45, 19, 0.18);
  background: var(--panel);
  box-shadow: 0 16px 36px rgba(37, 28, 16, 0.1);
}

.status-block {
  display: grid;
  gap: 6px;
}

.status-text,
.ai-reason {
  min-height: 3.2rem;
  margin: 0;
  color: var(--ink);
  font-size: 1.04rem;
  line-height: 1.5;
}

.ai-reason {
  color: var(--muted);
}

.controls {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.controls button {
  min-height: 44px;
  border: 1px solid var(--accent);
  border-radius: 6px;
  background: var(--accent);
  color: white;
  cursor: pointer;
  font-weight: 750;
}

.controls button:last-child {
  border-color: var(--ink);
  background: var(--ink);
}

.controls button:disabled {
  border-color: #c9bdaa;
  background: #d8ccba;
  color: #776d60;
  cursor: not-allowed;
}

.controls button:focus-visible {
  outline: 3px solid rgba(22, 97, 90, 0.35);
  outline-offset: 3px;
}

@media (max-width: 850px) {
  .game-layout {
    grid-template-columns: 1fr;
  }

  .board-wrap {
    margin: 0 auto;
  }

  .panel {
    width: min(calc(var(--cell-size) * 15 + 32px), 100%);
    margin: 0 auto;
  }
}

@media (max-width: 420px) {
  .app-shell {
    padding: 14px;
  }

  .controls {
    grid-template-columns: 1fr;
  }
}