* {
  box-sizing: border-box;
}

:root {
  --bg: #09111f;
  --bg-soft: #111c30;
  --card: rgba(16, 27, 47, 0.92);
  --card-border: rgba(255, 255, 255, 0.08);
  --text: #f4f8ff;
  --muted: #a9bad9;
  --primary: #67a7ff;
  --primary-2: #8b5cf6;
  --success: #38d39f;
  --warning: #ffbe55;
  --danger: #ff6d78;
  --shadow: 0 20px 40px rgba(0, 0, 0, 0.35);
  --radius-xl: 28px;
  --radius-lg: 20px;
  --radius-md: 14px;
}

html, body {
  margin: 0;
  min-height: 100%;
  font-family: 'Inter', sans-serif;
  background:
    radial-gradient(circle at top left, rgba(103, 167, 255, 0.18), transparent 28%),
    radial-gradient(circle at top right, rgba(139, 92, 246, 0.16), transparent 24%),
    linear-gradient(180deg, #060b16, #0b1527 55%, #08111f);
  color: var(--text);
}

a {
  color: inherit;
  text-decoration: none;
}

button,
input,
select {
  font: inherit;
}

.page-shell {
  width: min(1200px, calc(100% - 28px));
  margin: 0 auto;
  padding: 18px 0 40px;
}

.site-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 18px;
  padding: 20px 24px;
  border: 1px solid var(--card-border);
  border-radius: var(--radius-xl);
  background: rgba(9, 17, 31, 0.78);
  backdrop-filter: blur(16px);
  position: sticky;
  top: 14px;
  z-index: 20;
}

.brand-title {
  display: block;
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: 0.02em;
}

.brand-author {
  margin-top: 6px;
  color: var(--muted);
  font-size: 0.96rem;
}

.main-nav {
  display: flex;
  gap: 10px;
  align-items: center;
}

.main-nav a {
  padding: 10px 16px;
  border-radius: 999px;
  color: var(--muted);
  transition: 0.2s ease;
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--text);
  background: rgba(255, 255, 255, 0.08);
}

.menu-toggle {
  display: none;
  background: rgba(255, 255, 255, 0.08);
  color: var(--text);
  border: none;
  border-radius: 12px;
  padding: 8px 12px;
}

.main-content {
  margin-top: 24px;
  display: grid;
  gap: 24px;
}

.hero-card,
.section-card,
.game-panel,
.leaderboard-panel,
.notice-box {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow);
}

.hero-card {
  display: grid;
  grid-template-columns: 1.3fr 0.9fr;
  gap: 24px;
  padding: 28px;
}

.hero-copy h1,
.section-card h1,
.section-card h2,
.game-panel h1,
.game-panel h2 {
  margin: 10px 0 12px;
  line-height: 1.1;
}

.hero-copy p,
.section-card p,
.muted-text {
  color: var(--muted);
  line-height: 1.65;
}

.eyebrow {
  display: inline-block;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: #92b9ff;
}

.hero-actions,
.game-card-actions,
.stack-row,
.controls-row,
.top-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.primary-btn,
.secondary-btn,
.ghost-btn,
.control-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border-radius: 14px;
  padding: 12px 18px;
  border: none;
  cursor: pointer;
  transition: transform 0.15s ease, opacity 0.2s ease, background 0.2s ease;
  font-weight: 700;
}

.primary-btn,
.control-btn.primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-2));
  color: #fff;
}

.secondary-btn {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text);
}

.ghost-btn,
.control-btn.secondary {
  background: transparent;
  color: var(--text);
  border: 1px solid rgba(255, 255, 255, 0.12);
}

.primary-btn:hover,
.secondary-btn:hover,
.ghost-btn:hover,
.control-btn:hover {
  transform: translateY(-2px);
}

.stat-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
}

.stat-box {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 18px;
  padding: 18px;
}

.stat-number {
  display: block;
  font-size: 1.9rem;
  font-weight: 800;
}

.stat-label {
  display: block;
  color: var(--muted);
  margin-top: 6px;
}

.alert-card {
  margin-top: 18px;
  border-radius: 18px;
  padding: 14px 16px;
  border: 1px solid transparent;
}

.alert-card.warning {
  background: rgba(255, 190, 85, 0.09);
  border-color: rgba(255, 190, 85, 0.25);
}

.alert-card.success {
  background: rgba(56, 211, 159, 0.09);
  border-color: rgba(56, 211, 159, 0.25);
}

.section-card {
  padding: 24px;
}

.section-heading {
  display: flex;
  justify-content: space-between;
  align-items: end;
  gap: 16px;
  margin-bottom: 18px;
}

.game-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.game-card {
  position: relative;
  overflow: hidden;
  min-height: 220px;
  padding: 22px;
  border-radius: 24px;
  background: linear-gradient(180deg, rgba(255,255,255,0.12), rgba(255,255,255,0.03));
  border: 1px solid rgba(255,255,255,0.1);
  display: flex;
  flex-direction: column;
}


.game-card::after {
  content: '';
  position: absolute;
  inset: auto -60px -60px auto;
  width: 140px;
  height: 140px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
}

.game-card.from-pink { background-image: linear-gradient(160deg, rgba(255, 92, 141, 0.35), rgba(16, 27, 47, 0.9)); }
.game-card.from-gold { background-image: linear-gradient(160deg, rgba(255, 201, 87, 0.35), rgba(16, 27, 47, 0.9)); }
.game-card.from-green { background-image: linear-gradient(160deg, rgba(56, 211, 159, 0.35), rgba(16, 27, 47, 0.9)); }
.game-card.from-blue { background-image: linear-gradient(160deg, rgba(103, 167, 255, 0.35), rgba(16, 27, 47, 0.9)); }
.game-card.from-purple { background-image: linear-gradient(160deg, rgba(154, 103, 255, 0.35), rgba(16, 27, 47, 0.9)); }
.game-card.from-cyan { background-image: linear-gradient(160deg, rgba(68, 214, 255, 0.35), rgba(16, 27, 47, 0.9)); }

.game-icon {
  font-size: 2rem;
}

.game-card h3 {
  margin: 16px 0 8px;
  font-size: 1.3rem;
}

.game-card p {
  min-height: 70px;
  color: rgba(244,248,255,0.85);
}

.game-card-actions {
  margin-top: auto;
}

.two-column-section {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
}

.feature-list {
  display: grid;
  gap: 14px;
}

.feature-item {
  display: grid;
  gap: 6px;
  padding: 14px 16px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.06);
}

.ad-preview {
  margin-top: 18px;
}

.ad-label {
  color: var(--muted);
  margin-bottom: 8px;
}

.ad-box {
  min-height: 130px;
  border-radius: 18px;
  border: 2px dashed rgba(255, 255, 255, 0.18);
  display: grid;
  place-items: center;
  color: rgba(244,248,255,0.8);
}

.score-feed {
  display: grid;
  gap: 12px;
}

.version-chip {
  margin-top: 14px;
  display: inline-flex;
  align-items: center;
  padding: 10px 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.07);
  color: var(--text);
  border: 1px solid rgba(255, 255, 255, 0.08);
  font-weight: 700;
}

.quick-links-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.quick-game-link {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 58px;
  text-align: center;
  padding: 12px 16px;
  border-radius: 18px;
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.1);
  font-weight: 700;
}

.quick-game-link:hover {
  transform: translateY(-2px);
  background: rgba(255,255,255,0.09);
}

.score-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 12px 14px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.05);
}

.score-value {
  min-width: 80px;
  text-align: right;
  font-weight: 800;
  font-size: 1.2rem;
}

.roadmap-list {
  margin: 0;
  padding-left: 20px;
  color: var(--muted);
  line-height: 1.8;
}

.site-footer {
  margin-top: 24px;
  display: flex;
  justify-content: space-between;
  gap: 16px;
  color: var(--muted);
  padding: 16px 4px 0;
  font-size: 0.95rem;
}

.game-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) 360px;
  gap: 24px;
}

.game-panel {
  padding: 24px;
}

.panel-title-row {
  display: flex;
  justify-content: space-between;
  align-items: start;
  gap: 16px;
  margin-bottom: 18px;
}

.form-grid {
  display: grid;
  gap: 14px;
}

label span {
  display: block;
  margin-bottom: 8px;
  font-weight: 600;
}

.input,
.select,
.setup-input {
  width: 100%;
  padding: 12px 14px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.06);
  color: var(--text);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.input::placeholder,
.setup-input::placeholder {
  color: rgba(255, 255, 255, 0.4);
}

.score-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 18px;
}

.score-badge {
  padding: 12px 16px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.06);
}

.score-badge strong {
  display: block;
  font-size: 1.35rem;
}

.board-3x3 {
  width: min(100%, 460px);
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin: 0 auto;
}

.cell-btn {
  aspect-ratio: 1 / 1;
  border-radius: 20px;
  border: 1px solid rgba(255,255,255,0.12);
  background: rgba(255,255,255,0.06);
  color: var(--text);
  font-size: clamp(2rem, 6vw, 3.3rem);
  font-weight: 800;
  cursor: pointer;
}

.cell-btn:hover { background: rgba(255,255,255,0.1); }

.leaderboard-panel,
.notice-box {
  padding: 20px;
}

.leaderboard-list {
  display: grid;
  gap: 10px;
}

.leaderboard-item {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  align-items: center;
  padding: 10px 12px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.05);
}

.game-help-list {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
  line-height: 1.7;
}

.leaderboard-table {
  width: 100%;
  border-collapse: collapse;
}

.leaderboard-table th,
.leaderboard-table td {
  padding: 12px 10px;
  text-align: left;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.leaderboard-table-wrap {
  overflow-x: auto;
}

.sidebar-stack {
  display: grid;
  gap: 24px;
}

.leaderboard-panel h2,
.notice-box h2 {
  margin-top: 0;
}

option {
  color: #111827;
}

.setup-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.setup-grid .full {
  grid-column: 1 / -1;
}

.setup-note {
  padding: 14px 16px;
  border-radius: 16px;
  background: rgba(255,255,255,0.05);
  color: var(--muted);
}

.memory-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}

.memory-card {
  aspect-ratio: 1 / 1;
  border-radius: 18px;
  border: none;
  cursor: pointer;
  font-size: 2rem;
  background: linear-gradient(160deg, rgba(103, 167, 255, 0.85), rgba(139, 92, 246, 0.9));
  color: transparent;
  transition: transform 0.15s ease, opacity 0.2s ease;
}

.memory-card.revealed,
.memory-card.matched {
  background: rgba(255,255,255,0.12);
  color: #fff;
}

.memory-card:disabled {
  cursor: default;
}

.color-target-box {
  border-radius: 22px;
  min-height: 160px;
  display: grid;
  place-items: center;
  font-size: 1.6rem;
  font-weight: 800;
  margin-bottom: 18px;
  border: 1px solid rgba(255,255,255,0.1);
}

.color-options {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.color-choice {
  min-height: 92px;
  border-radius: 18px;
  border: none;
  cursor: pointer;
  color: #fff;
  font-weight: 800;
  font-size: 1rem;
}

#snake-canvas {
  width: 100%;
  max-width: 500px;
  aspect-ratio: 1 / 1;
  background: #050910;
  border-radius: 20px;
  border: 1px solid rgba(255,255,255,0.12);
  touch-action: none;
}

.game-2048-board {
  width: min(100%, 480px);
  aspect-ratio: 1 / 1;
  padding: 12px;
  border-radius: 22px;
  background: rgba(255,255,255,0.08);
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}

.tile {
  border-radius: 18px;
  display: grid;
  place-items: center;
  font-weight: 800;
  font-size: clamp(1.2rem, 3vw, 2rem);
  background: rgba(255,255,255,0.08);
  min-height: 86px;
}

.tile[data-value="0"] { color: transparent; }
.tile[data-value="2"] { background: #eee4da; color: #3c2f2f; }
.tile[data-value="4"] { background: #ede0c8; color: #3c2f2f; }
.tile[data-value="8"] { background: #f2b179; }
.tile[data-value="16"] { background: #f59563; }
.tile[data-value="32"] { background: #f67c5f; }
.tile[data-value="64"] { background: #f65e3b; }
.tile[data-value="128"] { background: #edcf72; color: #3c2f2f; }
.tile[data-value="256"] { background: #edcc61; color: #3c2f2f; }
.tile[data-value="512"] { background: #edc850; color: #3c2f2f; }
.tile[data-value="1024"] { background: #edc53f; color: #3c2f2f; }
.tile[data-value="2048"] { background: #edc22e; color: #3c2f2f; }
.tile[data-value="4096"],
.tile[data-value="8192"] { background: #9e69ff; }

.status-line {
  margin-top: 12px;
  padding: 12px 14px;
  border-radius: 14px;
  background: rgba(255,255,255,0.05);
  color: var(--muted);
  min-height: 48px;
}


.bubble-arena {
  position: relative;
  width: min(100%, 560px);
  height: 420px;
  border-radius: 24px;
  overflow: hidden;
  border: 1px solid rgba(255,255,255,0.12);
  background:
    radial-gradient(circle at 20% 20%, rgba(103, 167, 255, 0.18), transparent 20%),
    radial-gradient(circle at 80% 25%, rgba(139, 92, 246, 0.16), transparent 24%),
    radial-gradient(circle at 50% 80%, rgba(56, 211, 159, 0.12), transparent 24%),
    linear-gradient(180deg, rgba(255,255,255,0.05), rgba(255,255,255,0.02));
  margin-top: 18px;
}

.bubble-center-note {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  color: rgba(244,248,255,0.78);
  font-size: 1.15rem;
  font-weight: 700;
  text-align: center;
  padding: 24px;
}

.bubble-target {
  position: absolute;
  border: none;
  border-radius: 999px;
  cursor: pointer;
  color: #ffffff;
  font-weight: 800;
  letter-spacing: 0.05em;
  background:
    radial-gradient(circle at 30% 30%, rgba(255,255,255,0.88), rgba(255,255,255,0.2) 22%, rgba(103,167,255,0.95) 55%, rgba(139,92,246,0.96) 100%);
  box-shadow:
    inset 0 8px 18px rgba(255,255,255,0.25),
    0 12px 28px rgba(103, 167, 255, 0.25);
  animation: bubble-float 1.8s ease-in-out infinite alternate;
}

.bubble-target span {
  pointer-events: none;
  text-shadow: 0 2px 8px rgba(0,0,0,0.25);
}

.bubble-target:hover {
  transform: scale(1.06);
}

.bubble-target.burst {
  transform: scale(1.16);
  opacity: 0;
  transition: transform 0.12s ease, opacity 0.12s ease;
}

@keyframes bubble-float {
  from {
    transform: translateY(0px);
  }
  to {
    transform: translateY(-8px);
  }
}

.hidden {
  display: none !important;
}

@media (max-width: 980px) {
  .hero-card,
  .two-column-section,
  .game-layout,
  .setup-grid,
  .game-grid,
  .quick-links-grid {
    grid-template-columns: 1fr;
  }

  .main-nav {
    display: none;
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    flex-direction: column;
    align-items: stretch;
    min-width: 220px;
    padding: 12px;
    background: rgba(9, 17, 31, 0.95);
    border: 1px solid var(--card-border);
    border-radius: 18px;
  }

  .main-nav.open {
    display: flex;
  }

  .site-header {
    position: relative;
  }

  .menu-toggle {
    display: inline-flex;
  }

  .site-footer,
  .section-heading,
  .panel-title-row {
    flex-direction: column;
    align-items: start;
  }
}

@media (max-width: 680px) {
  .page-shell {
    width: min(100% - 20px, 1200px);
  }

  .site-header,
  .hero-card,
  .section-card,
  .game-panel,
  .leaderboard-panel,
  .notice-box {
    padding: 18px;
    border-radius: 22px;
  }

  .memory-grid,
  .color-options {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .board-3x3 {
    gap: 10px;
  }
}