/* ============================================================
   5×5 Tic-Tac-Toe — dark navy + glowing accents
   X = electric cyan (#00d4ff)
   O = warm amber   (#ffaa00)
   Grid: 5x5 (vs 4x4 in the 4x4 project — only css-grid changes)
   ============================================================ */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
/* Ensure the HTML hidden attribute always wins over any display rule */
[hidden] { display: none !important; }

:root {
  --bg:         #0f0f1a;
  --surface:    #1a1a2e;
  --surface2:   #22223b;
  --border:     #2e2e4a;
  --text:       #e0e0f0;
  --text-dim:   #666688;
  --x-color:    #00d4ff;
  --x-glow:     rgba(0, 212, 255, 0.25);
  --o-color:    #ffaa00;
  --o-glow:     rgba(255, 170, 0, 0.25);
  --accent:     #7c6df0;
  --win-glow:   rgba(124, 109, 240, 0.4);
  /* 5×5 cells are slightly smaller to fit comfortably */
  --cell-size:  min(14vw, 88px);
  --gap:        min(1.8vw, 8px);
  --radius:     10px;
  --font-main:  'Inter', system-ui, sans-serif;
  --font-mono:  'JetBrains Mono', monospace;
}

/* ── Layout ── */
body {
  font-family: var(--font-main);
  background: var(--bg);
  color: var(--text);
  min-height: 100dvh;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  padding: 32px 16px 48px;
}

/* Subtle animated grid background */
.bg-grid {
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(124,109,240,0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(124,109,240,0.04) 1px, transparent 1px);
  background-size: 40px 40px;
  pointer-events: none;
  z-index: 0;
}

.container {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
  width: 100%;
  max-width: 560px;
}

/* ── Title ── */
.title-block { text-align: center; }

h1 {
  font-size: clamp(1.9rem, 6vw, 2.8rem);
  font-weight: 700;
  letter-spacing: -0.5px;
  color: var(--text);
}

.accent { color: var(--accent); }

.subtitle {
  margin-top: 6px;
  font-size: 0.88rem;
  color: var(--text-dim);
  letter-spacing: 0.3px;
}

/* ── Side selection ── */
.side-select {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  padding: 12px 0;
}

.choose-label {
  font-size: 0.95rem;
  color: var(--text-dim);
}

.side-btns { display: flex; gap: 20px; }

.side-btn {
  width: 100px;
  height: 100px;
  border-radius: var(--radius);
  border: 2px solid var(--border);
  background: var(--surface);
  font-family: var(--font-mono);
  font-size: 2.4rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease, border-color 0.15s ease;
}

.side-btn:hover { transform: translateY(-3px); }

.x-btn { color: var(--x-color); border-color: rgba(0,212,255,0.3); }
.x-btn:hover {
  border-color: var(--x-color);
  box-shadow: 0 0 24px var(--x-glow), 0 0 8px var(--x-glow);
}

.o-btn { color: var(--o-color); border-color: rgba(255,170,0,0.3); }
.o-btn:hover {
  border-color: var(--o-color);
  box-shadow: 0 0 24px var(--o-glow), 0 0 8px var(--o-glow);
}

.engine-status {
  font-size: 0.75rem;
  color: var(--text-dim);
  font-family: var(--font-mono);
  letter-spacing: 0.2px;
}
.engine-status.ready { color: #4ade80; }
.engine-status.error { color: #f87171; }

/* ── Game board — KEY CHANGE: 5 columns/rows ── */
.board-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}

.board {
  display: grid;
  grid-template-columns: repeat(5, var(--cell-size));
  grid-template-rows:    repeat(5, var(--cell-size));
  gap: var(--gap);
}

/* ── Cells (identical logic to 4x4) ── */
.cell {
  background: var(--surface);
  border: 2px solid var(--border);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: calc(var(--cell-size) * 0.40);
  font-weight: 700;
  cursor: pointer;
  transition: border-color 0.15s, box-shadow 0.15s, background 0.15s, transform 0.12s;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
  position: relative;
  overflow: hidden;
}

.cell::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: calc(var(--radius) - 2px);
  opacity: 0;
  transition: opacity 0.15s;
}

.cell.hoverable:hover {
  border-color: var(--accent);
  transform: scale(1.05);
  box-shadow: 0 0 16px rgba(124,109,240,0.3);
}

.cell.x {
  color: var(--x-color);
  border-color: rgba(0,212,255,0.4);
  cursor: default;
  animation: popIn 0.2s ease-out;
}
.cell.x::after { background: radial-gradient(circle, var(--x-glow), transparent 70%); opacity: 1; }

.cell.o {
  color: var(--o-color);
  border-color: rgba(255,170,0,0.4);
  cursor: default;
  animation: popIn 0.2s ease-out;
}
.cell.o::after { background: radial-gradient(circle, var(--o-glow), transparent 70%); opacity: 1; }

.cell.winner {
  border-color: var(--accent);
  background: var(--surface2);
  box-shadow: 0 0 20px var(--win-glow), inset 0 0 12px var(--win-glow);
  animation: winPulse 1s ease-in-out infinite alternate;
}

.cell.thinking {
  animation: breathe 0.8s ease-in-out infinite alternate;
}

@keyframes popIn {
  0%   { transform: scale(0.65); opacity: 0.3; }
  60%  { transform: scale(1.09); }
  100% { transform: scale(1);   opacity: 1; }
}

@keyframes winPulse {
  from { box-shadow: 0 0 14px var(--win-glow), inset 0 0 6px var(--win-glow); }
  to   { box-shadow: 0 0 30px var(--win-glow), inset 0 0 18px var(--win-glow); }
}

@keyframes breathe {
  from { border-color: var(--border); }
  to   { border-color: rgba(124,109,240,0.5); }
}

/* ── Status bar ── */
.status-bar {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 28px;
  font-size: 0.88rem;
  letter-spacing: 0.3px;
  color: var(--text-dim);
  min-width: 260px;
  text-align: center;
  transition: color 0.2s;
}

.status-bar.your-turn { color: var(--accent); }
.status-bar.cpu-turn  { color: var(--text-dim); }
.status-bar.x-wins    { color: var(--x-color); }
.status-bar.o-wins    { color: var(--o-color); }
.status-bar.draw      { color: var(--text); }

/* ── Move-source indicator ── */
.move-info {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.3px;
  color: var(--text-dim);
  min-height: 1.4em;
  text-align: center;
  transition: color 0.25s;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
}

/* Dot that pulses briefly when the indicator updates */
.move-info::before {
  content: '';
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
  opacity: 0;
  flex-shrink: 0;
  transition: opacity 0.2s;
}

.move-info.book {
  color: var(--o-color);   /* warm amber — book is "known territory" */
}
.move-info.book::before  { opacity: 0.7; }

.move-info.engine {
  color: var(--x-color);   /* cyan — engine is "thinking live" */
}
.move-info.engine::before { opacity: 0.7; }

@keyframes dotPop {
  0%   { transform: scale(1.8); opacity: 0.9; }
  100% { transform: scale(1);   opacity: 0.7; }
}
.move-info.update::before { animation: dotPop 0.35s ease-out forwards; }

/* ── Forced-draw toggle ── */
.settings-row {
  display: flex;
  justify-content: center;
}

.toggle-label {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.72rem;
  color: var(--text-dim);
  font-family: var(--font-mono);
  cursor: pointer;
  user-select: none;
  letter-spacing: 0.2px;
  transition: color 0.15s;
}

.toggle-label:hover { color: var(--text); }

.toggle-switch {
  position: relative;
  width: 34px;
  height: 20px;
  flex-shrink: 0;
}

.toggle-switch input {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle-knob {
  position: absolute;
  inset: 0;
  background: var(--surface2);
  border: 1.5px solid var(--border);
  border-radius: 10px;
  transition: background 0.2s, border-color 0.2s;
}

.toggle-knob::after {
  content: '';
  position: absolute;
  width: 13px;
  height: 13px;
  background: var(--text-dim);
  border-radius: 50%;
  top: 2px;
  left: 2px;
  transition: transform 0.2s ease, background 0.2s;
}

.toggle-switch input:checked + .toggle-knob {
  background: rgba(124, 109, 240, 0.15);
  border-color: var(--accent);
}

.toggle-switch input:checked + .toggle-knob::after {
  transform: translateX(14px);
  background: var(--accent);
}

/* ── Replay button ── */
.replay-btn {
  background: transparent;
  border: 1.5px solid var(--border);
  border-radius: 8px;
  color: var(--text-dim);
  font-family: var(--font-main);
  font-size: 0.85rem;
  padding: 8px 22px;
  cursor: pointer;
  letter-spacing: 0.3px;
  transition: border-color 0.15s, color 0.15s, box-shadow 0.15s;
}

.replay-btn:hover {
  border-color: var(--accent);
  color: var(--text);
  box-shadow: 0 0 12px rgba(124,109,240,0.2);
}

/* ── Footer ── */
.footer {
  font-size: 0.72rem;
  color: var(--text-dim);
  text-align: center;
}

.footer a { color: var(--accent); text-decoration: none; }
.footer a:hover { text-decoration: underline; }

/* ── Responsive: tighten grid on very small screens ── */
@media (max-width: 400px) {
  :root { --cell-size: 16.5vw; --gap: 2vw; }
  h1 { font-size: 1.5rem; }
  .side-btn { width: 80px; height: 80px; font-size: 2rem; }
}