:root {
  --bg-deep: #0a0a12;
  --bg-panel: rgba(255, 255, 255, 0.04);
  --border-subtle: rgba(255, 255, 255, 0.08);
  --text-primary: #f0f0f5;
  --text-muted: #8888a0;
  --accent-cyan: #00e5ff;
  --accent-purple: #a855f7;
  --felt-1: #0d3b2e;
  --felt-2: #072019;
  --card-radius: calc(var(--card-w) * 0.075);
  --font: 'Outfit', system-ui, sans-serif;
}

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

body {
  font-family: var(--font);
  background: var(--bg-deep);
  color: var(--text-primary);
  min-height: 100vh;
  overflow: hidden;
  -webkit-user-select: none;
  user-select: none;
}

.game-layout {
  display: flex;
  flex-direction: column;
  height: 100vh;
}

/* ---------- Header ---------- */
.game-header {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  padding: 0.9rem 1.5rem;
  border-bottom: 1px solid var(--border-subtle);
  background: rgba(10, 10, 18, 0.6);
  backdrop-filter: blur(12px);
  z-index: 5;
}

.back-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color 0.2s;
  white-space: nowrap;
}

.back-link:hover { color: var(--accent-cyan); }

.game-header h1 {
  font-size: 1.5rem;
  font-weight: 600;
  background: linear-gradient(135deg, var(--text-primary), var(--accent-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  white-space: nowrap;
}

.header-stats {
  display: flex;
  gap: 1.25rem;
  margin-left: auto;
}

.stat { text-align: center; }

.stat-label {
  display: block;
  font-size: 0.65rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
}

.stat-value {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--accent-cyan);
  font-variant-numeric: tabular-nums;
}

.header-actions { display: flex; gap: 0.6rem; }

.btn {
  font-family: var(--font);
  font-size: 0.85rem;
  font-weight: 600;
  padding: 0.5rem 1rem;
  border: 1px solid var(--border-subtle);
  border-radius: 100px;
  background: var(--bg-panel);
  color: var(--text-primary);
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.2s, border-color 0.2s;
  white-space: nowrap;
}

.btn:hover {
  transform: translateY(-1px);
  border-color: rgba(0, 229, 255, 0.4);
}

.btn--primary {
  background: linear-gradient(135deg, #00e5ff, #0099cc);
  color: #0a0a12;
  border-color: transparent;
}

.btn--primary:hover { box-shadow: 0 0 24px rgba(0, 229, 255, 0.4); }

/* ---------- Board ---------- */
.board-wrapper {
  flex: 1;
  overflow: auto;
  display: flex;
  justify-content: center;
  background:
    radial-gradient(ellipse at 50% 0%, rgba(0, 229, 255, 0.05), transparent 60%),
    radial-gradient(ellipse at 100% 100%, rgba(168, 85, 247, 0.05), transparent 55%);
}

.board {
  position: relative;
  margin: 1.5rem auto;
  /* width & height set by JS */
}

/* Pile placeholders */
.pile-slot {
  position: absolute;
  width: var(--card-w);
  height: var(--card-h);
  border-radius: var(--card-radius);
  border: 1.5px solid rgba(255, 255, 255, 0.09);
  background: rgba(255, 255, 255, 0.02);
  box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: border-color 0.2s, box-shadow 0.2s, background 0.2s;
}

.pile-slot__mark {
  font-size: calc(var(--card-w) * 0.4);
  color: rgba(255, 255, 255, 0.09);
  font-weight: 300;
  line-height: 1;
}

.pile-slot--foundation .pile-slot__mark { font-weight: 400; }

.pile-slot--recycle { cursor: pointer; }
.pile-slot--recycle:hover { border-color: rgba(0, 229, 255, 0.35); }

.pile-slot--drop-target {
  border-color: var(--accent-cyan);
  background: rgba(0, 229, 255, 0.08);
  box-shadow: inset 0 0 24px rgba(0, 229, 255, 0.18), 0 0 18px rgba(0, 229, 255, 0.15);
}

/* ---------- Cards ---------- */
.card {
  position: absolute;
  top: 0;
  left: 0;
  width: var(--card-w);
  height: var(--card-h);
  will-change: transform;
  transition: transform 0.34s cubic-bezier(0.2, 0.9, 0.3, 1);
  transform-style: preserve-3d;
}

.card__inner {
  position: absolute;
  inset: 0;
  transform-style: preserve-3d;
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  border-radius: var(--card-radius);
}

.card.face-down .card__inner { transform: rotateY(180deg); }

.card__front,
.card__back {
  position: absolute;
  inset: 0;
  border-radius: var(--card-radius);
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  overflow: hidden;
  /* Reliable face hiding across engines. Safari/WebKit ignores
     `backface-visibility: hidden` for these nested 3D faces and would
     otherwise render the card front straight through the back. Swapping
     opacity — with a delay equal to half the 0.4s flip — guarantees only
     one face is ever visible, switching at the midpoint of the rotateY. */
  transition: opacity 0s linear 0.2s;
}
.card__back { opacity: 0; }
.card.face-down .card__front { opacity: 0; }
.card.face-down .card__back { opacity: 1; }

/* Card front */
.card__front {
  background:
    linear-gradient(160deg, #ffffff 0%, #f4f6fb 55%, #e9edf6 100%);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.9),
    inset 0 0 0 1px rgba(0, 0, 0, 0.06),
    0 calc(var(--card-w) * 0.03) calc(var(--card-w) * 0.09) rgba(0, 0, 0, 0.45);
  color: #1a1a2e;
}

.card.red .card__front { color: #d81e5b; }

.card__corner {
  position: absolute;
  display: flex;
  flex-direction: column;
  align-items: center;
  line-height: 0.92;
  font-weight: 700;
}

.card__corner--tl { top: calc(var(--card-h) * 0.05); left: calc(var(--card-w) * 0.07); }
.card__corner--br {
  bottom: calc(var(--card-h) * 0.05);
  right: calc(var(--card-w) * 0.07);
  transform: rotate(180deg);
}

.card__corner .rank {
  font-size: calc(var(--card-w) * 0.24);
  letter-spacing: -0.03em;
}
.card__corner .suit { font-size: calc(var(--card-w) * 0.18); margin-top: -0.06em; }

/* Pip layout */
.card__pips { position: absolute; inset: 0; }

.pip {
  position: absolute;
  transform: translate(-50%, -50%);
  font-size: calc(var(--card-w) * 0.28);
  line-height: 1;
}
.pip.flip { transform: translate(-50%, -50%) rotate(180deg); }

/* Face cards */
.card__face-art {
  position: absolute;
  inset: calc(var(--card-w) * 0.06);
  border-radius: calc(var(--card-radius) * 0.7);
  border: 1.5px solid currentColor;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background:
    repeating-linear-gradient(45deg, rgba(0,0,0,0.02) 0 6px, transparent 6px 12px),
    linear-gradient(160deg, rgba(0,0,0,0.015), rgba(0,0,0,0.05));
}

.card.red .card__face-art {
  background:
    repeating-linear-gradient(45deg, rgba(216,30,91,0.05) 0 6px, transparent 6px 12px),
    linear-gradient(160deg, rgba(216,30,91,0.03), rgba(216,30,91,0.08));
}

.card__face-letter {
  font-size: calc(var(--card-w) * 0.5);
  font-weight: 700;
  opacity: 0.9;
  position: relative;
  z-index: 1;
}

.card__face-suit {
  position: absolute;
  font-size: calc(var(--card-w) * 0.75);
  opacity: 0.14;
}

/* Card back */
.card__back {
  transform: rotateY(180deg);
  background:
    linear-gradient(135deg, #10163a 0%, #1b1152 50%, #2a1466 100%);
  box-shadow:
    inset 0 0 0 1px rgba(255, 255, 255, 0.08),
    0 calc(var(--card-w) * 0.03) calc(var(--card-w) * 0.09) rgba(0, 0, 0, 0.45);
}

.card__back::before {
  content: "";
  position: absolute;
  inset: calc(var(--card-w) * 0.06);
  border-radius: calc(var(--card-radius) * 0.6);
  border: 1.5px solid rgba(0, 229, 255, 0.35);
  background-image:
    radial-gradient(circle at 30% 30%, rgba(0, 229, 255, 0.22), transparent 45%),
    radial-gradient(circle at 70% 70%, rgba(168, 85, 247, 0.28), transparent 45%),
    repeating-linear-gradient(45deg, rgba(255,255,255,0.05) 0 3px, transparent 3px 8px),
    repeating-linear-gradient(-45deg, rgba(255,255,255,0.05) 0 3px, transparent 3px 8px);
}

.card__back::after {
  content: "◆";
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: calc(var(--card-w) * 0.35);
  color: rgba(0, 229, 255, 0.55);
  text-shadow: 0 0 14px rgba(0, 229, 255, 0.7);
}

/* Interaction states */
.card.movable .card__front { cursor: grab; }

.card.dragging {
  transition: none;
  cursor: grabbing;
  /* z-index is set per-card in JS (10000 + i) to keep the dragged stack in
     order; don't override it here with !important. */
}
.card.dragging .card__front {
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.9),
    inset 0 0 0 1px rgba(0, 0, 0, 0.06),
    0 calc(var(--card-w) * 0.12) calc(var(--card-w) * 0.22) rgba(0, 0, 0, 0.55);
}

.card.hint .card__front {
  animation: hint-pulse 0.7s ease;
}

@keyframes hint-pulse {
  0%, 100% { box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.9),
    inset 0 0 0 1px rgba(0, 0, 0, 0.06),
    0 calc(var(--card-w) * 0.03) calc(var(--card-w) * 0.09) rgba(0, 0, 0, 0.45); }
  50% { box-shadow:
    inset 0 0 0 2px var(--accent-cyan),
    0 0 22px rgba(0, 229, 255, 0.6); }
}

.card.just-landed .card__front {
  animation: land-bounce 0.3s ease;
}
@keyframes land-bounce {
  0% { filter: brightness(1.25); }
  100% { filter: brightness(1); }
}

/* ---------- Win overlay ---------- */
.overlay {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(10, 10, 18, 0.72);
  backdrop-filter: blur(10px);
  z-index: 10000;
  animation: fade-in 0.4s ease;
}
@keyframes fade-in { from { opacity: 0; } to { opacity: 1; } }

.overlay--hidden { display: none; }

.overlay-content {
  text-align: center;
  padding: 2.5rem 3rem;
  border: 1px solid var(--border-subtle);
  border-radius: 24px;
  background: rgba(255, 255, 255, 0.04);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.6), 0 0 60px rgba(0, 229, 255, 0.1);
}

.win-trophy {
  font-size: 2.5rem;
  letter-spacing: 0.3rem;
  margin-bottom: 0.75rem;
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-purple));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: trophy-float 2.5s ease-in-out infinite;
}
@keyframes trophy-float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

.overlay-content h2 {
  font-size: 2.2rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
}
.overlay-content p { color: var(--text-muted); margin-bottom: 1.75rem; }

/* Confetti */
.confetti {
  position: fixed;
  top: -20px;
  width: 10px;
  height: 14px;
  border-radius: 2px;
  z-index: 9999;
  pointer-events: none;
  animation: confetti-fall linear forwards;
}
@keyframes confetti-fall {
  0% { transform: translateY(-20px) rotate(0deg); opacity: 1; }
  100% { transform: translateY(105vh) rotate(720deg); opacity: 0.9; }
}

@media (max-width: 640px) {
  .game-header { flex-wrap: wrap; gap: 0.75rem 1rem; padding: 0.75rem 1rem; }
  .game-header h1 { font-size: 1.2rem; }
  .header-stats { gap: 0.9rem; }
  .btn { padding: 0.45rem 0.8rem; font-size: 0.8rem; }
}