/* ═══════════════════════════════════════════════
   Popzor — Dark neon aesthetic, mobile-first
   ═══════════════════════════════════════════════ */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:        #0a0a12;
  --surface:   #12121f;
  --border:    #1e1e35;

  /* Player colours — player 0 = blue (human), player 1 = red (CPU) */
  --c0:        #33aaff;
  --c0-glow:   rgba(51, 170, 255, 0.55);
  --c1:        #ff3366;
  --c1-glow:   rgba(255, 51, 102, 0.55);

  --text:      #e0e0f0;
  --muted:     #666688;
  --accent:    #7b4fff;
  --accent-glow: rgba(123, 79, 255, 0.5);

  --cell-gap:  3px;
  --radius:    6px;
}

html, body {
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: 'Segoe UI', system-ui, sans-serif;
  overflow: hidden;
}

/* ── Screens ─────────────────────────────────── */
.screen {
  display: none;
  position: fixed;
  inset: 0;
  align-items: center;
  justify-content: center;
}
.screen.active { display: flex; }

/* ── Main Menu ───────────────────────────────── */
.menu-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  padding: 32px 24px;
  width: min(420px, 95vw);
}

.logo {
  font-size: clamp(3rem, 12vw, 5rem);
  font-weight: 900;
  letter-spacing: 0.12em;
  background: linear-gradient(135deg, var(--c0), var(--accent), var(--c1));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  text-shadow: none;
  filter: drop-shadow(0 0 18px var(--accent-glow));
}

.tagline {
  color: var(--muted);
  font-size: 0.85rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.menu-buttons {
  display: flex;
  flex-direction: column;
  gap: 12px;
  width: 100%;
}

/* ── Buttons ─────────────────────────────────── */
.btn {
  padding: 14px 28px;
  border: none;
  border-radius: var(--radius);
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.1s, box-shadow 0.1s, filter 0.15s;
  user-select: none;
}
.btn:active { transform: scale(0.97); }

.btn-primary {
  background: linear-gradient(135deg, #1e1240, #2a1a5e);
  color: var(--text);
  border: 1px solid var(--accent);
  box-shadow: 0 0 12px var(--accent-glow), inset 0 0 8px rgba(123,79,255,0.1);
}
.btn-primary:hover:not(:disabled) {
  filter: brightness(1.3);
  box-shadow: 0 0 22px var(--accent-glow);
}
.btn-primary:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.btn-back {
  background: transparent;
  color: var(--muted);
  font-size: 0.9rem;
  padding: 8px 16px;
}
.btn-back:hover { color: var(--text); }

.btn-exit {
  background: transparent;
  color: var(--muted);
  font-size: 0.8rem;
  padding: 6px 12px;
  border: 1px solid var(--border);
  border-radius: 4px;
}
.btn-exit:hover { color: var(--text); border-color: var(--muted); }

.btn-sm {
  padding: 6px 12px;
  font-size: 0.8rem;
  background: var(--surface);
  color: var(--muted);
  border: 1px solid var(--border);
  border-radius: 4px;
}

/* ── Online screen ───────────────────────────── */
.conn-status {
  font-size: 0.85rem;
  color: var(--muted);
  padding: 6px 14px;
  border-radius: 20px;
  border: 1px solid var(--border);
}
.conn-status.connected {
  color: #44ff88;
  border-color: #44ff88;
  box-shadow: 0 0 10px rgba(68,255,136,0.3);
}

.waiting-msg {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--muted);
  font-size: 0.9rem;
  animation: pulse 1.5s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0.5; }
}

.hidden { display: none !important; }

/* ── Game screen ─────────────────────────────── */
#screen-game {
  flex-direction: column;
  align-items: stretch;   /* override .screen's center so children fill full width */
  justify-content: flex-start;
  overflow: hidden;
}

.game-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 10px 16px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.header-center {
  display: flex;
  align-items: center;
  gap: 16px;
}

.player-tag {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  font-weight: 600;
  opacity: 0.5;
  transition: opacity 0.3s, filter 0.3s;
}
.player-tag.active {
  opacity: 1;
  filter: drop-shadow(0 0 6px currentColor);
}

.dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  flex-shrink: 0;
}
.dot-0 { background: var(--c0); box-shadow: 0 0 8px var(--c0-glow); }
.dot-1 { background: var(--c1); box-shadow: 0 0 8px var(--c1-glow); }

.turn-indicator {
  font-size: 0.8rem;
  color: var(--muted);
  text-align: center;
  letter-spacing: 0.05em;
  white-space: nowrap;
}

#board-container {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 12px;
  overflow: hidden;
}

#game-canvas {
  display: block;
  cursor: pointer;
  border-radius: var(--radius);
}

/* ── Win overlay ─────────────────────────────── */
#win-overlay {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,0.75);
  display: flex;
  align-items: center;
  justify-content: center;
  backdrop-filter: blur(6px);
  z-index: 10;
}

.win-box {
  background: var(--surface);
  border: 1px solid var(--accent);
  border-radius: 12px;
  padding: 40px 48px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  box-shadow: 0 0 40px var(--accent-glow);
  text-align: center;
}

.win-box h2 {
  font-size: 2rem;
  background: linear-gradient(135deg, var(--c0), var(--accent), var(--c1));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* ── Rules bar ───────────────────────────────── */
#rules-bar {
  flex-shrink: 0;
  background: var(--surface);
  border-top: 1px solid var(--border);
}

.rules-toggle {
  width: 100%;
  background: transparent;
  border: none;
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 8px 16px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: color 0.2s;
}
.rules-toggle:hover { color: var(--text); }

.rules-arrow {
  display: inline-block;
  transition: transform 0.25s;
  font-size: 0.65rem;
}
.rules-toggle[aria-expanded="true"] .rules-arrow {
  transform: rotate(180deg);
}

.rules-content {
  padding: 10px 20px 14px;
  animation: slideDown 0.2s ease;
}
@keyframes slideDown {
  from { opacity: 0; transform: translateY(-6px); }
  to   { opacity: 1; transform: translateY(0); }
}

.rules-content ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.rules-content li {
  font-size: 0.8rem;
  color: var(--muted);
  padding-left: 14px;
  position: relative;
  line-height: 1.5;
}
.rules-content li::before {
  content: '›';
  position: absolute;
  left: 0;
  color: var(--accent);
}
.rules-content strong {
  color: var(--text);
}