/* ========================================
   Memory Cards - game4.fun UI System
   Dark glassmorphism with neon accents
======================================== */

:root {
  --bg-dark: #050510;
  --bg-card: rgba(20, 20, 35, 0.8);
  --primary-neon: #6366f1;
  --secondary-neon: #ec4899;
  --accent-cyan: #06b6d4;
  --text-main: #f1f5f9;
  --text-dim: rgba(148, 163, 184, 0.7);
  --border-glass: rgba(255, 255, 255, 0.1);
  --radius-xl: 24px;
  --radius-lg: 16px;
  --radius-md: 12px;
  --radius-sm: 8px;
  --card-flip-speed: 0.5s;
}

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

body {
  background: var(--bg-dark);
  color: var(--text-main);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

/* Background ambient glow */
body::before {
  content: '';
  position: fixed;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background:
    radial-gradient(circle at 30% 20%, rgba(99, 102, 241, 0.08) 0%, transparent 50%),
    radial-gradient(circle at 70% 80%, rgba(236, 72, 153, 0.06) 0%, transparent 50%),
    radial-gradient(circle at 50% 50%, rgba(6, 182, 212, 0.04) 0%, transparent 60%);
  z-index: -1;
  animation: ambientDrift 20s ease-in-out infinite alternate;
}

@keyframes ambientDrift {
  0% { transform: translate(0, 0) rotate(0deg); }
  100% { transform: translate(-2%, -1%) rotate(3deg); }
}

/* ========== Game Container ========== */
.game-container {
  flex: 1;
  max-width: 800px;
  width: 100%;
  margin: 0 auto;
  padding: 0 16px 32px;
}

.game-header {
  text-align: center;
  padding: 24px 0 8px;
}

.game-header h1 {
  font-size: clamp(1.8rem, 5vw, 2.4rem);
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary-neon), var(--secondary-neon));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.subtitle {
  color: var(--text-dim);
  font-size: 0.95rem;
  margin-top: 4px;
}

/* ========== Controls ========== */
.controls {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 0;
  flex-wrap: wrap;
}

.difficulty-selector {
  display: flex;
  align-items: center;
  gap: 10px;
}

.difficulty-selector label {
  font-size: 0.85rem;
  color: var(--text-dim);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.difficulty-btns {
  display: flex;
  gap: 4px;
  background: rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-sm);
  padding: 3px;
  border: 1px solid var(--border-glass);
}

.diff-btn {
  background: transparent;
  border: none;
  color: var(--text-dim);
  padding: 6px 14px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.85rem;
  font-weight: 600;
  transition: all 0.25s ease;
}

.diff-btn:hover {
  color: var(--text-main);
  background: rgba(255, 255, 255, 0.06);
}

.diff-btn.active {
  background: var(--primary-neon);
  color: #fff;
  box-shadow: 0 0 12px rgba(99, 102, 241, 0.4);
}

.new-game-btn {
  background: linear-gradient(135deg, var(--primary-neon), var(--secondary-neon));
  border: none;
  color: #fff;
  padding: 10px 24px;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 16px rgba(99, 102, 241, 0.3);
}

.new-game-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(99, 102, 241, 0.45);
}

.new-game-btn:active {
  transform: translateY(0);
}

/* ========== Stats Bar ========== */
.stats-bar {
  display: flex;
  justify-content: space-around;
  gap: 8px;
  padding: 14px 20px;
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-glass);
  backdrop-filter: blur(16px);
  margin-bottom: 20px;
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.stat-label {
  font-size: 0.7rem;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 600;
}

.stat-value {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--accent-cyan);
  font-variant-numeric: tabular-nums;
}

/* ========== Game Board ========== */
.board-wrapper {
  display: flex;
  justify-content: center;
  padding: 8px 0;
}

.board {
  display: grid;
  gap: 10px;
  width: 100%;
  max-width: 600px;
  perspective: 1200px;
}

.board[data-cols="4"] {
  grid-template-columns: repeat(4, 1fr);
}

.board[data-cols="6"] {
  grid-template-columns: repeat(6, 1fr);
}

/* ========== Card ========== */
.card {
  aspect-ratio: 1;
  cursor: pointer;
  position: relative;
  transform-style: preserve-3d;
  transition: transform var(--card-flip-speed) cubic-bezier(0.4, 0, 0.2, 1);
}

.card.flipped {
  transform: rotateY(180deg);
}

.card.matched {
  transform: rotateY(180deg);
}

.card.matched .card-front {
  box-shadow:
    0 0 16px rgba(99, 102, 241, 0.5),
    0 0 40px rgba(99, 102, 241, 0.2),
    inset 0 0 16px rgba(99, 102, 241, 0.1);
  border-color: var(--primary-neon);
}

.card.matched .card-front::after {
  content: '';
  position: absolute;
  inset: -4px;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, var(--primary-neon), var(--secondary-neon));
  opacity: 0.15;
  z-index: -1;
  animation: matchGlow 1.5s ease-in-out infinite alternate;
}

@keyframes matchGlow {
  0% { opacity: 0.1; transform: scale(1); }
  100% { opacity: 0.25; transform: scale(1.04); }
}

.card.matched.just-matched {
  animation: matchBounce 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

@keyframes matchBounce {
  0% { transform: rotateY(180deg) scale(1); }
  40% { transform: rotateY(180deg) scale(1.15); }
  70% { transform: rotateY(180deg) scale(0.95); }
  100% { transform: rotateY(180deg) scale(1); }
}

.card-face {
  position: absolute;
  inset: 0;
  border-radius: var(--radius-lg);
  backface-visibility: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: box-shadow 0.3s ease;
}

.card-back {
  background: linear-gradient(145deg, rgba(30, 30, 50, 0.9), rgba(15, 15, 30, 0.95));
  border: 1.5px solid var(--border-glass);
  backdrop-filter: blur(8px);
  z-index: 2;
}

.card-back::before {
  content: '?';
  font-size: clamp(1.4rem, 4vw, 2rem);
  font-weight: 900;
  background: linear-gradient(135deg, var(--primary-neon), var(--accent-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  opacity: 0.6;
}

.card-back::after {
  content: '';
  position: absolute;
  inset: 6px;
  border-radius: calc(var(--radius-lg) - 4px);
  border: 1px dashed rgba(99, 102, 241, 0.2);
}

.card:not(.flipped):not(.matched):hover .card-back {
  box-shadow: 0 0 20px rgba(99, 102, 241, 0.25);
  border-color: rgba(99, 102, 241, 0.35);
}

.card-front {
  background: var(--bg-card);
  border: 1.5px solid var(--border-glass);
  backdrop-filter: blur(8px);
  transform: rotateY(180deg);
  font-size: clamp(1.8rem, 6vw, 3rem);
}

.card.no-click {
  pointer-events: none;
}

/* ========== Win Modal ========== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.4s ease;
}

.modal-overlay.active {
  opacity: 1;
  pointer-events: all;
}

.modal {
  background: linear-gradient(160deg, rgba(25, 25, 45, 0.95), rgba(15, 15, 30, 0.98));
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-xl);
  padding: 40px;
  text-align: center;
  max-width: 400px;
  width: 90%;
  transform: scale(0.8) translateY(20px);
  transition: transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
  box-shadow: 0 24px 64px rgba(0, 0, 0, 0.5), 0 0 40px rgba(99, 102, 241, 0.1);
}

.modal-overlay.active .modal {
  transform: scale(1) translateY(0);
}

.modal h2 {
  font-size: 2rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--primary-neon), var(--secondary-neon));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 16px;
}

.stars {
  font-size: 2.5rem;
  margin-bottom: 8px;
  letter-spacing: 8px;
}

.star-msg {
  color: var(--text-dim);
  font-size: 0.95rem;
  margin-bottom: 24px;
}

.win-stats {
  display: flex;
  justify-content: center;
  gap: 32px;
  margin-bottom: 28px;
}

.win-stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.win-stat-label {
  font-size: 0.75rem;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-weight: 600;
}

.win-stat-value {
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--accent-cyan);
}

.play-again-btn {
  background: linear-gradient(135deg, var(--primary-neon), var(--secondary-neon));
  border: none;
  color: #fff;
  padding: 14px 40px;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.35);
}

.play-again-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 28px rgba(99, 102, 241, 0.5);
}

/* ========== Ad Container ========== */
.g4f-ad-container {
  max-width: 800px;
  margin: 20px auto;
  padding: 24px;
  text-align: center;
  background: var(--bg-card);
  border: 1px dashed var(--border-glass);
  border-radius: var(--radius-lg);
}

.ad-placeholder-content {
  color: var(--text-dim);
  font-size: 0.85rem;
}

/* ========== Footer ========== */
.footer {
  text-align: center;
  padding: 20px;
  color: var(--text-dim);
  font-size: 0.8rem;
}

/* ========== Responsive ========== */
@media (max-width: 480px) {
  .controls {
    flex-direction: column;
    align-items: stretch;
  }

  .difficulty-selector {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .difficulty-btns {
    width: 100%;
  }

  .diff-btn {
    flex: 1;
    text-align: center;
  }

  .new-game-btn {
    width: 100%;
  }

  .stats-bar {
    padding: 10px 12px;
    gap: 4px;
  }

  .stat-label {
    font-size: 0.6rem;
  }

  .stat-value {
    font-size: 0.95rem;
  }

  .board {
    gap: 6px;
  }

  .card-front {
    font-size: clamp(1.2rem, 5vw, 2rem);
  }

  .card-back::before {
    font-size: 1.2rem;
  }

  .modal {
    padding: 28px 24px;
  }
}

@media (max-width: 360px) {
  .board {
    gap: 4px;
  }
}

/* ========== Card entrance animation ========== */
.card {
  opacity: 0;
  animation: cardEntrance 0.4s ease forwards;
}

@keyframes cardEntrance {
  from {
    opacity: 0;
    transform: scale(0.6) rotateY(0deg);
  }
  to {
    opacity: 1;
    transform: scale(1) rotateY(0deg);
  }
}

/* Stagger is applied via inline style animation-delay */