/* =========================================================
   Tic-Tac-Toe AI — Stylesheet
   Design language: clean "control room" feel — deep navy
   backdrop, crisp card, one confident accent color (cyan)
   used sparingly for X, and a warm coral for O.
   ========================================================= */

:root {
  --bg-navy: #0b1120;
  --bg-navy-2: #131b30;
  --card-bg: #ffffff;
  --card-border: #e7eaf3;
  --text-dark: #1b2136;
  --text-muted: #6b7280;

  --x-color: #0891b2;      /* cyan — human player */
  --x-color-light: #e0f7fa;
  --o-color: #f2542d;      /* warm coral — AI player */
  --o-color-light: #fdeae2;

  --win-highlight: #ffd166;
  --shadow-card: 0 20px 60px rgba(11, 17, 32, 0.35);
  --radius-lg: 22px;
  --radius-md: 14px;
}

* {
  box-sizing: border-box;
}

html, body {
  height: 100%;
}
body {
  margin: 0;
  font-family: "Poppins", sans-serif;
  background: radial-gradient(circle at 25% 15%, var(--bg-navy-2), var(--bg-navy) 65%);
  min-height: 100vh;
  display: flex;
  flex-direction: column;   /* card aur footer ko vertically stack karega */
  align-items: center;
  justify-content: center;
  padding: 24px;
  position: relative;
  overflow: hidden;
}

/* ============ Ambient background glows ============ */
.bg-glow {
  position: fixed;
  border-radius: 50%;
  filter: blur(90px);
  z-index: 0;
  opacity: 0.25;
}
.glow-1 {
  width: 380px;
  height: 380px;
  background: var(--x-color);
  top: -100px;
  left: -100px;
}
.glow-2 {
  width: 340px;
  height: 340px;
  background: var(--o-color);
  bottom: -100px;
  right: -80px;
}

/* ============ Main game card ============ */
.game-card {
  position: relative;
  z-index: 1;
  width: 420px;
  max-width: 94vw;
  background: var(--card-bg);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  padding: 30px 28px 26px;
  animation: cardIn 0.5s ease;
}

@keyframes cardIn {
  from { opacity: 0; transform: translateY(18px) scale(0.97); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

/* ============ Header ============ */
.game-header {
  text-align: center;
  margin-bottom: 18px;
}

.game-header h1 {
  margin: 0;
  font-size: 26px;
  font-weight: 700;
  color: var(--text-dark);
  letter-spacing: -0.5px;
}

.game-header h1 .accent {
  color: var(--x-color);
}

.subtitle {
  margin: 6px 0 0;
  font-size: 12.5px;
  color: var(--text-muted);
  font-weight: 500;
}

/* ============ Status bar ============ */
.status-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  background: #f6f8fc;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-md);
  padding: 12px 16px;
  margin-bottom: 16px;
  transition: background 0.3s ease, border-color 0.3s ease;
}

.status-icon {
  width: 26px;
  height: 26px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: "Space Mono", monospace;
  font-weight: 700;
  font-size: 14px;
  background: var(--x-color-light);
  color: var(--x-color);
  transition: all 0.25s ease;
}

.status-text {
  margin: 0;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-dark);
}

/* State modifiers applied via JS */
.status-bar.turn-o .status-icon {
  background: var(--o-color-light);
  color: var(--o-color);
}
.status-bar.win {
  background: #eafaf0;
  border-color: #b7ecc9;
}
.status-bar.lose {
  background: #fdeeea;
  border-color: #f6c6ba;
}
.status-bar.draw {
  background: #fff8e6;
  border-color: #ffe5a3;
}

/* ============ Score board ============ */
.score-board {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 20px;
}

.score-item {
  flex: 1;
  text-align: center;
  background: #f6f8fc;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-md);
  padding: 10px 6px;
}

.score-label {
  display: block;
  font-size: 10.5px;
  text-transform: uppercase;
  letter-spacing: 0.4px;
  color: var(--text-muted);
  font-weight: 600;
  margin-bottom: 4px;
}

.score-value {
  display: block;
  font-family: "Space Mono", monospace;
  font-size: 20px;
  font-weight: 700;
  color: var(--text-dark);
}

/* ============ Game board grid ============ */
.board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 22px;
}

.cell {
  aspect-ratio: 1 / 1;
  background: #f6f8fc;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-md);
  font-family: "Space Mono", monospace;
  font-size: 42px;
  font-weight: 700;
  color: var(--text-dark);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s ease, transform 0.15s ease, box-shadow 0.2s ease;
  user-select: none;
}

/* Hover only when the cell is empty and clickable */
.cell:not(.filled):not(.locked):hover {
  background: #eef2fb;
  transform: translateY(-2px);
  box-shadow: 0 6px 14px rgba(11, 17, 32, 0.08);
}

.cell:active:not(.filled):not(.locked) {
  transform: translateY(0) scale(0.97);
}

/* Filled cell colors depending on symbol */
.cell.x-mark {
  color: var(--x-color);
}
.cell.o-mark {
  color: var(--o-color);
}

/* Pop-in animation when a mark is placed */
.cell.filled .mark-inner {
  display: inline-block;
  animation: markIn 0.28s ease;
}

@keyframes markIn {
  from { opacity: 0; transform: scale(0.4) rotate(-10deg); }
  to { opacity: 1; transform: scale(1) rotate(0); }
}

/* Winning cells glow */
.cell.win-cell {
  background: #fff6dd;
  border-color: var(--win-highlight);
  box-shadow: 0 0 0 2px var(--win-highlight) inset;
  animation: winPulse 0.9s ease infinite;
}

@keyframes winPulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.04); }
}

/* Locked = board disabled while AI "thinks" or game over */
.cell.locked {
  cursor: not-allowed;
}

/* ============ Controls ============ */
.controls {
  display: flex;
  justify-content: center;
}

.restart-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--text-dark);
  color: #fff;
  border: none;
  padding: 12px 22px;
  border-radius: 30px;
  font-family: "Poppins", sans-serif;
  font-size: 13.5px;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.2s ease;
}

.restart-btn:hover {
  background: #2b3350;
  transform: translateY(-2px);
}

.restart-btn:active {
  transform: translateY(0) scale(0.97);
}

.restart-icon {
  font-size: 15px;
}

/* ============ Result overlay ============ */
.result-overlay {
  position: fixed;
  inset: 0;
  background: rgba(11, 17, 32, 0.55);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
  animation: overlayIn 0.25s ease;
}
/* When the `hidden` attribute is present, force it to stay hidden —
   otherwise our `display: flex` above overrides the browser's
   default hidden styling and the overlay shows on page load. */
.result-overlay[hidden] {
  display: none;
}

@keyframes overlayIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.result-card {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 34px 30px;
  text-align: center;
  width: 320px;
  max-width: 88vw;
  box-shadow: var(--shadow-card);
  animation: resultIn 0.35s ease;
}

@keyframes resultIn {
  from { opacity: 0; transform: translateY(20px) scale(0.94); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

.result-emoji {
  font-size: 46px;
  margin-bottom: 10px;
}

.result-title {
  margin: 0 0 8px;
  font-size: 22px;
  font-weight: 700;
  color: var(--text-dark);
}

.result-desc {
  margin: 0 0 22px;
  font-size: 13.5px;
  color: var(--text-muted);
}

.play-again-btn {
  background: var(--x-color);
  color: #fff;
  border: none;
  padding: 12px 26px;
  border-radius: 30px;
  font-family: "Poppins", sans-serif;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.2s ease;
}

.play-again-btn:hover {
  background: #067188;
  transform: translateY(-2px);
}
/* ============ Footer ============ */
.app-footer {
  position: relative;
  z-index: 1;
  text-align: center;
  margin-top: 18px;
}

.app-footer p {
  margin: 0;
  font-size: 12.5px;
  color: #cbd3e6;
  font-weight: 500;
}

.footer-highlight {
  color: var(--x-color);
  font-weight: 600;
}

/* ============ Mobile responsiveness ============ */
@media (max-width: 420px) {
  .game-card {
    padding: 24px 18px 20px;
  }
  .cell {
    font-size: 34px;
  }
  .game-header h1 {
    font-size: 22px;
  }
}