/* ==========================================================================
   Tic-Tac-Toe — modern, mobile-first UI
   Dark/light friendly, rounded corners, subtle shadows, smooth transitions.
   ========================================================================== */

:root {
  --primary: #4f46e5;
  --primary-hover: #4338ca;
  --primary-soft: #eef2ff;
  --secondary: #e2e8f0;
  --secondary-hover: #cbd5e1;
  --secondary-text: #334155;
  --bg: #f1f5f9;
  --bg-grad: radial-gradient(1200px 600px at 50% -10%, #e0e7ff 0%, #f1f5f9 55%);
  --surface: #ffffff;
  --text: #0f172a;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --x-color: #e11d48;      /* X = red */
  --o-color: #2563eb;      /* O = blue */
  --win-bg: #dcfce7;
  --win-border: #86efac;
  --win-text: #166534;
  --shadow-sm: 0 1px 2px rgb(15 23 42 / 0.06), 0 1px 3px rgb(15 23 42 / 0.08);
  --shadow: 0 6px 16px -6px rgb(15 23 42 / 0.18), 0 2px 6px -2px rgb(15 23 42 / 0.10);
  --shadow-lg: 0 24px 48px -20px rgb(15 23 42 / 0.35), 0 8px 20px -12px rgb(15 23 42 / 0.20);
  --radius: 16px;
  --radius-sm: 12px;
  --transition: 160ms cubic-bezier(0.4, 0, 0.2, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --primary: #818cf8;
    --primary-hover: #a5b4fc;
    --primary-soft: #1e1b4b;
    --secondary: #334155;
    --secondary-hover: #475569;
    --secondary-text: #e2e8f0;
    --bg: #0b1220;
    --bg-grad: radial-gradient(1200px 600px at 50% -10%, #1e1b4b 0%, #0b1220 55%);
    --surface: #111a2e;
    --text: #e2e8f0;
    --text-muted: #94a3b8;
    --border: #24304a;
    --x-color: #fb7185;
    --o-color: #60a5fa;
    --win-bg: #052e1a;
    --win-border: #166534;
    --win-text: #86efac;
    --shadow-sm: 0 1px 2px rgb(0 0 0 / 0.4);
    --shadow: 0 6px 16px -6px rgb(0 0 0 / 0.5);
    --shadow-lg: 0 24px 48px -20px rgb(0 0 0 / 0.7);
  }
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Inter, sans-serif;
  background: var(--bg);
  background-image: var(--bg-grad);
  background-attachment: fixed;
  color: var(--text);
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 2rem 1rem;
  padding-left: max(1rem, env(safe-area-inset-left));
  padding-right: max(1rem, env(safe-area-inset-right));
  padding-top: max(2rem, env(safe-area-inset-top));
  padding-bottom: max(2rem, env(safe-area-inset-bottom));
  line-height: 1.5;
  overflow-x: hidden;
}

.container {
  width: 100%;
  max-width: 440px;
  background: var(--surface);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border);
  padding: clamp(1rem, 4vw, 2rem);
}

header { text-align: center; margin-bottom: 1.5rem; }

header h1 {
  font-size: clamp(1.6rem, 7vw, 2.1rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  background: linear-gradient(120deg, var(--x-color), var(--o-color));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.status {
  margin-top: 0.5rem;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-muted);
  min-height: 1.5rem;
  transition: color var(--transition);
}

/* ---------------------------------------------------------------- home ---- */

.view[hidden] { display: none; }

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.35rem;
  box-shadow: var(--shadow-sm);
  width: 100%;
  max-width: 360px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

.hero-mark {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  font-size: 2rem;
  font-weight: 800;
  line-height: 1;
  margin-bottom: 0.25rem;
}
.hero-x { color: var(--x-color); }
.hero-o { color: var(--o-color); }

.field-label {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.text-input {
  width: 100%;
  padding: 0.8rem 0.95rem;
  font-size: 1rem;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--text);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition), background var(--transition);
  -webkit-appearance: none;
  appearance: none;
}
.text-input::placeholder { color: var(--text-muted); opacity: 0.75; }
.text-input:focus {
  border-color: var(--primary);
  background: var(--surface);
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--primary) 18%, transparent);
}

.home-actions { display: flex; flex-direction: column; gap: 0.55rem; }

.divider {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--text-muted);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.divider::before, .divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border);
}

.join-row { display: flex; gap: 0.5rem; }
.join-row .text-input { flex: 1; }
.join-row .btn { flex: 0 0 auto; }

.code-input {
  text-transform: uppercase;
  letter-spacing: 0.28em;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-weight: 700;
  text-align: center;
}

/* ------------------------------------------------------------ code banner -- */

.code-banner {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  justify-content: space-between;
  flex-wrap: wrap;
  background: linear-gradient(135deg, var(--primary-soft), var(--surface));
  border: 1.5px solid color-mix(in srgb, var(--primary) 30%, var(--border));
  border-radius: var(--radius);
  padding: 0.85rem 1rem;
  box-shadow: var(--shadow-sm);
  width: 100%;
  max-width: 360px;
  margin: 0 auto 1rem;
}
.code-banner[hidden] { display: none; }
.code-banner-main { display: flex; flex-direction: column; gap: 0.1rem; }
.code-label {
  font-size: 0.66rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-weight: 700;
  color: var(--text-muted);
}
.code-value {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 1.7rem;
  font-weight: 800;
  letter-spacing: 0.22em;
  color: var(--primary);
  line-height: 1.1;
}
.code-actions { display: flex; gap: 0.4rem; }

/* --------------------------------------------------------------- waiting -- */

.waiting {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.65rem;
  padding: 1.75rem 1rem;
  text-align: center;
}
.waiting[hidden] { display: none; }
.waiting .muted { color: var(--text-muted); font-size: 0.85rem; }

.spinner {
  width: 36px;
  height: 36px;
  border: 3px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.9s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ------------------------------------------------------------ game info --- */

.game-info {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  margin-bottom: 1rem;
  padding: 0.9rem 0.75rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.vs {
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  opacity: 0.7;
}

.player-info {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.3rem;
  padding: 0.4rem;
  border-radius: var(--radius-sm);
  border: 1.5px solid transparent;
  transition: background var(--transition), border-color var(--transition), transform var(--transition);
}
.player-info.active {
  background: var(--surface);
  border-color: color-mix(in srgb, var(--primary) 45%, var(--border));
  box-shadow: var(--shadow-sm);
}
.player-info.winner { border-color: var(--win-border); background: var(--win-bg); }

.mark-badge {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.15rem;
  font-weight: 800;
  background: var(--surface);
  border: 1.5px solid var(--border);
}
.mark-x { color: var(--x-color); }
.mark-o { color: var(--o-color); }

.player-info .name {
  font-size: 0.98rem;
  font-weight: 600;
  max-width: 100%;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.player-info.winner .name { color: var(--win-text); }

.player-info .score {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
}

.player-info .indicator {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--border);
  transition: background var(--transition), transform var(--transition);
}
.player-info.active[data-player="X"] .indicator {
  background: var(--x-color);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--x-color) 25%, transparent);
  transform: scale(1.25);
}
.player-info.active[data-player="O"] .indicator {
  background: var(--o-color);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--o-color) 25%, transparent);
  transform: scale(1.25);
}

/* --------------------------------------------------------------- board ---- */

.board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: clamp(6px, 2vw, 10px);
  aspect-ratio: 1;
  width: min(100%, 78vmin, 380px);
  margin: 0 auto 1rem;
  padding: clamp(6px, 2vw, 10px);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  touch-action: manipulation;
  user-select: none;
  -webkit-user-select: none;
}
.board[hidden] { display: none; }

.cell {
  background: var(--surface);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: clamp(2rem, 13vmin, 3.4rem);
  font-weight: 800;
  line-height: 1;
  cursor: pointer;
  transition: background var(--transition), border-color var(--transition),
              transform var(--transition), box-shadow var(--transition), color var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text);
  min-height: 44px;
  min-width: 44px;
  padding: 0;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
  -webkit-user-select: none;
  box-shadow: var(--shadow-sm);
}

@media (hover: hover) {
  .cell:hover:not(.filled):not(:disabled) {
    border-color: var(--primary);
    background: var(--primary-soft);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
  }
}
.cell:active:not(.filled):not(:disabled) {
  transform: scale(0.95);
  border-color: var(--primary);
}
.cell:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 2px;
}
.cell.filled { cursor: default; box-shadow: none; }

.cell.x { color: var(--x-color); animation: popIn 220ms cubic-bezier(0.34, 1.56, 0.64, 1); }
.cell.o { color: var(--o-color); animation: popIn 220ms cubic-bezier(0.34, 1.56, 0.64, 1); }

.cell.winning {
  background: var(--win-bg);
  border-color: var(--win-border);
  animation: pulse 1.2s ease infinite;
}

@keyframes popIn {
  0% { transform: scale(0.4); opacity: 0; }
  60% { transform: scale(1.12); }
  100% { transform: scale(1); opacity: 1; }
}
@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 0 color-mix(in srgb, var(--win-border) 55%, transparent); }
  50% { box-shadow: 0 0 0 10px transparent; }
}

/* ------------------------------------------------------ turn indicator ---- */

.turn-indicator {
  text-align: center;
  font-weight: 700;
  font-size: 1rem;
  padding: 0.7rem;
  border-radius: var(--radius-sm);
  background: var(--bg);
  border: 1.5px solid var(--border);
  margin-bottom: 0.9rem;
  transition: background var(--transition), border-color var(--transition), color var(--transition);
}
.turn-indicator.your-turn {
  background: var(--primary-soft);
  border-color: color-mix(in srgb, var(--primary) 45%, var(--border));
  color: var(--primary);
}
.turn-indicator.done {
  background: var(--win-bg);
  border-color: var(--win-border);
  color: var(--win-text);
}

/* --------------------------------------------------------- buttons -------- */

.controls {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}

.btn {
  padding: 0.8rem 1.5rem;
  border: 1.5px solid transparent;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 700;
  cursor: pointer;
  transition: background var(--transition), color var(--transition),
              border-color var(--transition), transform var(--transition), box-shadow var(--transition);
  min-width: 120px;
  min-height: 46px;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}
.btn:active:not(:disabled) { transform: scale(0.97); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn:focus-visible { outline: 2px solid var(--primary); outline-offset: 2px; }

.btn.primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 6px 16px -8px color-mix(in srgb, var(--primary) 80%, transparent);
}
.btn.primary:hover:not(:disabled) { background: var(--primary-hover); transform: translateY(-1px); }

.btn.secondary {
  background: var(--secondary);
  color: var(--secondary-text);
  border-color: var(--border);
}
.btn.secondary:hover:not(:disabled) { background: var(--secondary-hover); transform: translateY(-1px); }

.btn.small { padding: 0.45rem 0.75rem; font-size: 0.8rem; min-width: 0; min-height: 36px; border-radius: 10px; }

/* ---------------------------------------------------- connection status --- */

.connection-status {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-size: 0.83rem;
  color: var(--text-muted);
}
.connection-status .dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--border);
  transition: background var(--transition);
}
.connection-status.connected .dot { background: #22c55e; box-shadow: 0 0 0 3px rgb(34 197 94 / 0.2); }
.connection-status.connecting .dot { background: #f59e0b; animation: blink 1s ease infinite; }
.connection-status.error .dot { background: #ef4444; }
.connection-status.local .dot { background: var(--primary); }
@keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: 0.3; } }

footer {
  text-align: center;
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 1.25rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
}

/* ------------------------------------------------------------- toast ------ */

.toast {
  position: fixed;
  left: 50%;
  bottom: max(1.25rem, env(safe-area-inset-bottom));
  transform: translateX(-50%);
  background: rgb(15 23 42 / 0.94);
  color: #fff;
  padding: 0.65rem 1.1rem;
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 600;
  z-index: 200;
  max-width: 90vw;
  text-align: center;
  box-shadow: var(--shadow-lg);
  animation: fadeIn 150ms ease;
}
.toast[hidden] { display: none; }
@keyframes fadeIn { from { opacity: 0; transform: translate(-50%, 8px); } to { opacity: 1; transform: translate(-50%, 0); } }

/* ------------------------------------------------------------ responsive -- */

@media (max-width: 480px) {
  body {
    align-items: flex-start;
    padding-top: max(0.75rem, env(safe-area-inset-top));
    padding-bottom: max(1rem, env(safe-area-inset-bottom));
    padding-left: max(0.75rem, env(safe-area-inset-left));
    padding-right: max(0.75rem, env(safe-area-inset-right));
  }
  .container {
    padding: clamp(0.85rem, 4vw, 1.5rem);
    min-height: calc(100dvh - 2rem);
    max-width: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    box-shadow: var(--shadow);
  }
  .game-info { margin-bottom: 0.85rem; padding: 0.7rem 0.5rem; }
  .controls { gap: 0.5rem; }
  .btn { flex: 1 1 auto; min-width: 0; padding: 0.75rem 0.9rem; font-size: 0.9rem; }
}

@media (max-width: 360px) {
  .code-banner { flex-direction: column; align-items: stretch; }
  .code-value { text-align: center; }
  .code-actions { justify-content: center; }
}

@media (max-height: 560px) and (orientation: landscape) {
  body { align-items: flex-start; padding-top: max(0.5rem, env(safe-area-inset-top)); padding-bottom: max(0.5rem, env(safe-area-inset-bottom)); }
  .container {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    column-gap: 1.5rem;
    align-items: center;
    max-width: 760px;
  }
  header, footer { grid-column: 1 / -1; }
  .board { width: min(52vmin, 300px); margin: 0 auto; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}