* {
  box-sizing: border-box;
}

:root {
  --card-radius: 18px;
  --panel-bg: rgba(15, 23, 42, 0.72);
  --panel-border: rgba(148, 163, 184, 0.25);
}

body {
  min-height: 100vh;
  margin: 0;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  background: radial-gradient(circle at top, #26324a 0%, #111827 45%, #0f172a 100%);
  color: #f8fafc;
  font-family: Arial, sans-serif;
}

button,
input,
select {
  font: inherit;
}

button {
  appearance: none;
}

button:focus-visible,
input:focus-visible,
select:focus-visible {
  outline: 3px solid #93c5fd;
  outline-offset: 3px;
}

.game-container {
  width: min(94vw, 980px);
  padding: 32px 16px 48px;
  text-align: center;
}

.hero {
  margin-bottom: 24px;
}

.eyebrow {
  margin: 0 0 8px;
  color: #93c5fd;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

h1,
h2,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 0;
  font-size: clamp(2rem, 5vw, 3.5rem);
}

.subtitle {
  max-width: 620px;
  margin: 12px auto 0;
  color: #cbd5e1;
  line-height: 1.6;
}

.setup-panel,
.stats-panel,
.leaderboard-card {
  border: 1px solid var(--panel-border);
  border-radius: 22px;
  background: var(--panel-bg);
  box-shadow: 0 18px 36px rgba(0, 0, 0, 0.18);
}

.setup-panel {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr auto;
  gap: 14px;
  align-items: end;
  margin-bottom: 18px;
  padding: 16px;
}

.setup-field {
  display: grid;
  gap: 8px;
  text-align: left;
}

.setup-field span,
.stat-label {
  color: #94a3b8;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.setup-field input,
.setup-field select {
  width: 100%;
  min-height: 44px;
  border: 1px solid rgba(148, 163, 184, 0.35);
  border-radius: 14px;
  background: rgba(15, 23, 42, 0.92);
  color: #f8fafc;
  padding: 0 12px;
}

.stats-panel {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 12px;
  margin-bottom: 18px;
  padding: 12px;
}

.stat-card {
  padding: 14px;
  border: 1px solid rgba(148, 163, 184, 0.18);
  border-radius: 16px;
  background: rgba(2, 6, 23, 0.38);
}

.stat-label {
  display: block;
  margin-bottom: 6px;
}

.stat-value {
  font-size: 1.35rem;
  font-weight: 700;
}

.status-message {
  min-height: 24px;
  margin-bottom: 16px;
  color: #bfdbfe;
  font-weight: 700;
}

.game-board {
  --columns: 4;
  display: grid;
  grid-template-columns: repeat(var(--columns), minmax(42px, 84px));
  justify-content: center;
  gap: 10px;
  margin: 0 auto 24px;
}

.card {
  position: relative;
  width: 100%;
  aspect-ratio: 1;
  border: 0;
  border-radius: var(--card-radius);
  background: transparent;
  cursor: pointer;
  perspective: 900px;
}

.card-face {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--card-radius);
  font-size: clamp(1.4rem, 4vw, 2.3rem);
  font-weight: 700;
  backface-visibility: hidden;
  transition: transform 0.35s ease, box-shadow 0.35s ease, background-color 0.25s ease;
}

.card-front {
  background: linear-gradient(135deg, #2563eb, #7c3aed);
  color: #eff6ff;
  box-shadow: 0 12px 24px rgba(37, 99, 235, 0.22);
}

.card-back {
  background: #f8fafc;
  color: #0f172a;
  transform: rotateY(180deg);
}

.card.flipped .card-front,
.card.matched .card-front {
  transform: rotateY(180deg);
}

.card.flipped .card-back,
.card.matched .card-back {
  transform: rotateY(360deg);
}

.card.peeked .card-back {
  box-shadow: 0 0 24px rgba(147, 197, 253, 0.55);
}

.card.matched .card-back {
  background: #86efac;
  box-shadow: 0 0 24px rgba(134, 239, 172, 0.45);
}

.card.wrong .card-back {
  background: #fecaca;
  animation: shake 0.25s ease-in-out 2;
}

.action-row,
.modal-actions {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

.action-row {
  margin-bottom: 24px;
}

.primary-btn,
.secondary-btn {
  min-height: 44px;
  padding: 12px 20px;
  border: 0;
  border-radius: 999px;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 700;
  transition: transform 0.2s ease, box-shadow 0.2s ease, opacity 0.2s ease;
}

.primary-btn {
  background: #f8fafc;
  color: #111827;
}

.secondary-btn {
  background: rgba(148, 163, 184, 0.18);
  color: #f8fafc;
}

.danger-btn {
  color: #fecaca;
}

.primary-btn:hover,
.secondary-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 24px rgba(0, 0, 0, 0.28);
}

.primary-btn:active,
.secondary-btn:active {
  transform: translateY(0);
}

.leaderboard-card {
  max-width: 720px;
  margin: 0 auto;
  padding: 18px;
  text-align: left;
}

.leaderboard-header {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
  margin-bottom: 12px;
}

.leaderboard-filter {
  display: grid;
  gap: 6px;
  min-width: 120px;
}

.leaderboard-filter span {
  color: #94a3b8;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.leaderboard-filter select {
  min-height: 40px;
  border: 1px solid rgba(148, 163, 184, 0.35);
  border-radius: 12px;
  background: rgba(15, 23, 42, 0.92);
  color: #f8fafc;
  padding: 0 10px;
}

.leaderboard-header h2 {
  margin-bottom: 0;
}

.leaderboard-header p {
  margin-bottom: 0;
  color: #94a3b8;
  font-size: 0.9rem;
}

.leaderboard-list {
  display: grid;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style-position: inside;
}

.leaderboard-entry,
.empty-leaderboard {
  display: grid;
  grid-template-columns: 56px 1fr 90px 90px 70px 90px 70px;
  gap: 8px;
  align-items: center;
  padding: 12px;
  border-radius: 14px;
  background: rgba(2, 6, 23, 0.34);
}

.empty-leaderboard {
  display: block;
  color: #cbd5e1;
  text-align: center;
}

.rank,
.leaderboard-name {
  font-weight: 700;
}

.modal-overlay {
  position: fixed;
  z-index: 1000;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(2, 6, 23, 0.72);
}

.modal-overlay.hidden {
  display: none;
}

.modal-card {
  width: min(92vw, 460px);
  padding: 28px;
  border: 1px solid var(--panel-border);
  border-radius: 24px;
  background: #0f172a;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.42);
  text-align: center;
}

.modal-emoji {
  margin-bottom: 8px;
  font-size: 3rem;
}

.modal-summary {
  color: #cbd5e1;
  line-height: 1.6;
}

@keyframes shake {
  0%, 100% {
    transform: rotateY(360deg) translateX(0);
  }

  50% {
    transform: rotateY(360deg) translateX(5px);
  }
}

@media (max-width: 860px) {
  .setup-panel,
  .stats-panel {
    grid-template-columns: 1fr 1fr;
  }

  .setup-panel .primary-btn {
    grid-column: 1 / -1;
  }

  .game-board {
    gap: 8px;
  }

  .leaderboard-header {
    display: block;
  }

  .leaderboard-filter {
    margin-top: 12px;
  }

  .leaderboard-entry {
    grid-template-columns: 44px 1fr;
  }
}

@media (max-width: 520px) {
  .game-container {
    padding-top: 24px;
  }

  .setup-panel,
  .stats-panel {
    grid-template-columns: 1fr;
  }

  .game-board {
    grid-template-columns: repeat(var(--columns), minmax(34px, 1fr));
    gap: 6px;
  }

  .card-face {
    border-radius: 12px;
    font-size: clamp(1rem, 6vw, 1.7rem);
  }
}