:root {
  --bg: #f4f1e8;
  --panel: rgba(255, 255, 255, 0.82);
  --text: #24231f;
  --muted: #6a675f;
  --line: #5a3d21;
  --board: #d7a85d;
  --board-dark: #c69045;
  --accent: #2f6c5a;
  --danger: #b63a34;
  --shadow: 0 14px 40px rgba(45, 35, 20, 0.14);
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  min-height: 100vh;
  min-height: 100dvh;
  overflow-x: hidden;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(255,255,255,.9), transparent 36%),
    linear-gradient(135deg, #f7f4ec, #ece6d8);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans JP", sans-serif;
  -webkit-tap-highlight-color: transparent;
}

button, select { font: inherit; }
button { cursor: pointer; }
button, select { touch-action: manipulation; }

.app {
  width: min(1180px, calc(100% - 24px));
  margin: 0 auto;
  padding: max(24px, env(safe-area-inset-top)) 0 max(40px, env(safe-area-inset-bottom));
}

.hero {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 18px;
}

.eyebrow {
  margin: 0 0 4px;
  color: var(--accent);
  font-weight: 800;
  letter-spacing: .18em;
  font-size: .72rem;
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 3.6rem);
  letter-spacing: .04em;
}

.subtitle { margin: 5px 0 0; color: var(--muted); }

.turn-card {
  min-width: 190px;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 15px;
  border: 1px solid rgba(0,0,0,.08);
  border-radius: 16px;
  background: var(--panel);
  box-shadow: var(--shadow);
  backdrop-filter: blur(8px);
}

.turn-card small { display: block; color: var(--muted); margin-bottom: 2px; }
.turn-card strong { font-size: 1.02rem; }

.turn-stone, .mini-stone {
  display: inline-block;
  flex: 0 0 auto;
  border-radius: 50%;
}
.turn-stone { width: 34px; height: 34px; }
.mini-stone { width: 14px; height: 14px; vertical-align: -2px; margin-right: 5px; }
.black { background: radial-gradient(circle at 30% 25%, #565656 0, #1a1a1a 48%, #050505 100%); box-shadow: inset -2px -3px 5px rgba(0,0,0,.45), inset 2px 2px 4px rgba(255,255,255,.18); }
.white { background: radial-gradient(circle at 30% 25%, #fff 0, #f3f3f3 45%, #cfcfcf 100%); box-shadow: inset -2px -3px 5px rgba(0,0,0,.16), inset 2px 2px 4px rgba(255,255,255,.8), 0 0 0 1px rgba(0,0,0,.16); }

.controls {
  display: grid;
  grid-template-columns: repeat(2, minmax(170px, 1fr)) minmax(250px, auto);
  gap: 12px;
  align-items: end;
  padding: 14px;
  margin-bottom: 18px;
  border-radius: 18px;
  background: var(--panel);
  box-shadow: var(--shadow);
  border: 1px solid rgba(0,0,0,.07);
}

.controls label { display: grid; gap: 6px; min-width: 0; }
.controls label > span { font-size: .78rem; font-weight: 800; color: var(--muted); }
select, button {
  min-height: 44px;
  border-radius: 12px;
  border: 1px solid rgba(0,0,0,.12);
  background: white;
  padding: 0 12px;
}
select { width: 100%; }

.control-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}

.primary {
  color: white;
  background: var(--accent);
  border-color: var(--accent);
  font-weight: 800;
  padding-inline: 18px;
}
.primary:active, .secondary:active { transform: translateY(1px); }
.secondary { font-weight: 700; }
.secondary:hover { background: #f5f5f5; }
.secondary.compact { margin: 0; width: auto; }

.mobile-status { display: none; }

.game-area {
  display: grid;
  grid-template-columns: minmax(0, 760px) minmax(220px, 1fr);
  gap: 18px;
  align-items: start;
}

.board-wrap {
  position: relative;
  border-radius: 22px;
  padding: clamp(14px, 2vw, 22px);
  background: linear-gradient(145deg, #bd7d36, #8d5426);
  box-shadow: 0 20px 50px rgba(57, 35, 14, .24);
  overflow: hidden;
}

.board {
  width: min(100%, 700px);
  aspect-ratio: 1;
  position: relative;
  margin: 0 auto;
  border-radius: 8px;
  background-color: var(--board);
  background-image:
    repeating-linear-gradient(to right,
      transparent 0,
      transparent calc((100% - 1px) / 14 - .5px),
      var(--line) calc((100% - 1px) / 14 - .5px),
      var(--line) calc((100% - 1px) / 14 + .5px)),
    repeating-linear-gradient(to bottom,
      transparent 0,
      transparent calc((100% - 1px) / 14 - .5px),
      var(--line) calc((100% - 1px) / 14 - .5px),
      var(--line) calc((100% - 1px) / 14 + .5px));
  box-shadow: inset 0 0 28px rgba(73, 43, 13, .2);
  touch-action: pan-y;
  user-select: none;
  -webkit-user-select: none;
}

.board::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at 21.4286% 21.4286%, #3d2a18 0 3px, transparent 3.6px),
    radial-gradient(circle at 50% 21.4286%, #3d2a18 0 3px, transparent 3.6px),
    radial-gradient(circle at 78.5714% 21.4286%, #3d2a18 0 3px, transparent 3.6px),
    radial-gradient(circle at 21.4286% 50%, #3d2a18 0 3px, transparent 3.6px),
    radial-gradient(circle at 50% 50%, #3d2a18 0 3px, transparent 3.6px),
    radial-gradient(circle at 78.5714% 50%, #3d2a18 0 3px, transparent 3.6px),
    radial-gradient(circle at 21.4286% 78.5714%, #3d2a18 0 3px, transparent 3.6px),
    radial-gradient(circle at 50% 78.5714%, #3d2a18 0 3px, transparent 3.6px),
    radial-gradient(circle at 78.5714% 78.5714%, #3d2a18 0 3px, transparent 3.6px);
}

.cell {
  position: absolute;
  width: calc(100% / 14);
  height: calc(100% / 14);
  transform: translate(-50%, -50%);
  border: 0;
  padding: 0;
  min-height: 0;
  background: transparent;
  border-radius: 50%;
  z-index: 2;
}

@media (hover: hover) and (pointer: fine) {
  .cell:hover:not(.occupied)::after {
    content: "";
    position: absolute;
    inset: 21%;
    border-radius: 50%;
    background: rgba(0,0,0,.16);
  }
}

.cell:active:not(.occupied)::after {
  content: "";
  position: absolute;
  inset: 17%;
  border-radius: 50%;
  background: rgba(0,0,0,.18);
}
.cell:focus-visible { outline: 3px solid rgba(47,108,90,.9); outline-offset: -2px; }

.stone {
  position: absolute;
  inset: 11%;
  border-radius: 50%;
  transform: scale(.1);
  opacity: 0;
  animation: place .16s ease-out forwards;
  pointer-events: none;
}
.cell.last .stone::after {
  content: "";
  position: absolute;
  width: 20%;
  height: 20%;
  left: 40%;
  top: 40%;
  border-radius: 50%;
  background: #d9473f;
  box-shadow: 0 0 0 1px rgba(255,255,255,.25);
}

@keyframes place {
  0% { transform: scale(.2); opacity: .2; }
  80% { transform: scale(1.08); opacity: 1; }
  100% { transform: scale(1); opacity: 1; }
}

.thinking {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  border-radius: 22px;
  background: rgba(20, 18, 14, .34);
  color: white;
  font-weight: 800;
  z-index: 20;
  backdrop-filter: blur(2px);
}
.thinking[hidden] { display: none; }
.spinner {
  width: 22px;
  height: 22px;
  border: 3px solid rgba(255,255,255,.4);
  border-top-color: white;
  border-radius: 50%;
  animation: spin .7s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.info-panel { display: grid; gap: 12px; }
.info-panel > div {
  padding: 16px;
  border-radius: 18px;
  background: var(--panel);
  border: 1px solid rgba(0,0,0,.07);
  box-shadow: var(--shadow);
}
.info-panel h2 { margin: 0 0 10px; font-size: 1rem; }
.info-panel p { margin: 0; line-height: 1.65; color: var(--muted); }
.info-panel ul { margin: 0; padding-left: 20px; color: var(--muted); line-height: 1.65; }

.message {
  position: fixed;
  left: 50%;
  bottom: max(20px, calc(env(safe-area-inset-bottom) + 10px));
  transform: translate(-50%, 18px);
  min-width: min(440px, calc(100% - 28px));
  max-width: calc(100% - 28px);
  padding: 13px 18px;
  border-radius: 13px;
  background: rgba(30, 29, 26, .94);
  color: white;
  text-align: center;
  font-weight: 800;
  opacity: 0;
  pointer-events: none;
  transition: .18s ease;
  z-index: 50;
  box-shadow: 0 10px 30px rgba(0,0,0,.25);
}
.message.show { opacity: 1; transform: translate(-50%, 0); }
.message.error { background: rgba(166, 43, 38, .96); }
.message.success { background: rgba(36, 108, 76, .96); }

@media (max-width: 900px) {
  .game-area { grid-template-columns: 1fr; }
  .info-panel { grid-template-columns: repeat(3, 1fr); }
  .board { width: 100%; }
}

@media (max-width: 680px) {
  .app {
    width: 100%;
    padding: max(10px, env(safe-area-inset-top)) max(8px, env(safe-area-inset-right)) max(24px, env(safe-area-inset-bottom)) max(8px, env(safe-area-inset-left));
  }

  .hero {
    align-items: flex-end;
    gap: 8px;
    margin: 0 4px 10px;
  }
  .eyebrow { font-size: .62rem; letter-spacing: .13em; }
  h1 { font-size: clamp(1.7rem, 9vw, 2.35rem); line-height: 1; }
  .subtitle { font-size: .76rem; margin-top: 4px; }

  .turn-card {
    min-width: 0;
    gap: 8px;
    padding: 8px 10px;
    border-radius: 13px;
    box-shadow: 0 8px 24px rgba(45, 35, 20, 0.12);
  }
  .turn-stone { width: 25px; height: 25px; }
  .turn-card small { display: none; }
  .turn-card strong { font-size: .78rem; white-space: nowrap; }

  .controls {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 8px;
    margin-bottom: 8px;
    padding: 9px;
    border-radius: 14px;
    box-shadow: 0 8px 24px rgba(45, 35, 20, 0.11);
  }
  .controls label > span { font-size: .7rem; }
  select, button { min-height: 44px; border-radius: 10px; }
  select { font-size: 16px; padding: 0 8px; }
  .control-actions { grid-column: 1 / -1; }
  .control-actions button { font-size: .88rem; }

  .mobile-status {
    display: flex;
    align-items: center;
    gap: 8px;
    min-height: 38px;
    margin-bottom: 8px;
    padding: 7px 10px;
    border-radius: 12px;
    background: rgba(255,255,255,.78);
    border: 1px solid rgba(0,0,0,.06);
    font-size: .78rem;
    overflow: hidden;
  }
  .mobile-status strong { flex: 0 0 auto; color: var(--accent); }
  .mobile-status span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: var(--muted); }

  .game-area { gap: 8px; }
  .board-wrap {
    width: 100%;
    padding: 7px;
    border-radius: 13px;
    box-shadow: 0 12px 32px rgba(57, 35, 14, .2);
  }
  .board { border-radius: 5px; }
  .board::before {
    background:
      radial-gradient(circle at 21.4286% 21.4286%, #3d2a18 0 2px, transparent 2.5px),
      radial-gradient(circle at 50% 21.4286%, #3d2a18 0 2px, transparent 2.5px),
      radial-gradient(circle at 78.5714% 21.4286%, #3d2a18 0 2px, transparent 2.5px),
      radial-gradient(circle at 21.4286% 50%, #3d2a18 0 2px, transparent 2.5px),
      radial-gradient(circle at 50% 50%, #3d2a18 0 2px, transparent 2.5px),
      radial-gradient(circle at 78.5714% 50%, #3d2a18 0 2px, transparent 2.5px),
      radial-gradient(circle at 21.4286% 78.5714%, #3d2a18 0 2px, transparent 2.5px),
      radial-gradient(circle at 50% 78.5714%, #3d2a18 0 2px, transparent 2.5px),
      radial-gradient(circle at 78.5714% 78.5714%, #3d2a18 0 2px, transparent 2.5px);
  }
  .cell { width: calc(112% / 14); height: calc(112% / 14); }
  .stone { inset: 12%; }

  .info-panel { grid-template-columns: 1fr; }
  .status-box { display: none; }
  .rule-box, .legend-box { display: none; }

  .thinking { border-radius: 13px; font-size: .9rem; }
  .message {
    min-width: 0;
    width: calc(100% - 20px - env(safe-area-inset-left) - env(safe-area-inset-right));
    max-width: 420px;
    padding: 11px 13px;
    font-size: .88rem;
  }
}

@media (max-width: 400px) {
  .hero { align-items: center; }
  .subtitle { display: none; }
  .controls { grid-template-columns: 1fr; }
  .control-actions { grid-column: auto; }
  .controls label { grid-template-columns: 92px minmax(0, 1fr); align-items: center; gap: 8px; }
  .controls label > span { font-size: .72rem; }
  .control-actions { grid-template-columns: 1fr 1fr; }
}

@media (orientation: landscape) and (max-height: 540px) and (max-width: 950px) {
  .app { width: min(100% - 16px, 900px); padding-top: max(6px, env(safe-area-inset-top)); }
  .hero { margin-bottom: 6px; }
  .title-block .subtitle, .eyebrow { display: none; }
  h1 { font-size: 1.45rem; }
  .controls { margin-bottom: 6px; padding: 7px; }
  .game-area { grid-template-columns: minmax(0, calc(100vh - 155px)) minmax(220px, 1fr); }
  .info-panel { display: grid; grid-template-columns: 1fr; }
  .rule-box, .legend-box { display: none; }
  .status-box { display: block; }
  .board-wrap { padding: 6px; }
}