:root {
  --bg: #0f172a;
  --bg-soft: #111827;
  --panel: rgba(15, 23, 42, 0.88);
  --panel-border: rgba(148, 163, 184, 0.15);
  --text: #e5eefc;
  --muted: #9fb1c8;
  --primary: #38bdf8;
  --primary-deep: #0ea5e9;
  --accent: #34d399;
  --danger: #f87171;
  --warning: #fbbf24;
  --shadow: 0 18px 46px rgba(2, 8, 23, 0.34);
}

* {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  overflow-x: hidden;
}

body {
  margin: 0;
  min-height: 100vh;
  min-height: 100dvh;
  font-family: "Noto Sans SC", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  overscroll-behavior-y: contain;
  background:
    radial-gradient(circle at top, rgba(56, 189, 248, 0.16), transparent 28%),
    radial-gradient(circle at bottom right, rgba(52, 211, 153, 0.14), transparent 28%),
    linear-gradient(135deg, #020617 0%, #0f172a 55%, #111827 100%);
}

button,
kbd {
  font: inherit;
}

button {
  -webkit-tap-highlight-color: transparent;
}

.page-shell {
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding:
    max(18px, env(safe-area-inset-top))
    max(18px, env(safe-area-inset-right))
    max(18px, env(safe-area-inset-bottom))
    max(18px, env(safe-area-inset-left));
}

.game-card {
  width: min(980px, 100%);
  padding: clamp(14px, 2.2vw, 24px);
  border: 1px solid var(--panel-border);
  background: var(--panel);
  border-radius: 24px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
}

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

.eyebrow {
  margin: 0 0 6px;
  color: var(--primary);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 0.78rem;
  font-weight: 700;
}

h1 {
  margin: 0;
  font-size: clamp(1.7rem, 3vw, 2.4rem);
  line-height: 1.1;
}

.subtitle {
  margin: 10px 0 0;
  max-width: 620px;
  color: var(--muted);
  line-height: 1.65;
  font-size: 0.96rem;
}

.score-panel,
.tips-card,
.action-card,
.mobile-controls {
  border: 1px solid rgba(148, 163, 184, 0.14);
  background: rgba(15, 23, 42, 0.72);
  border-radius: 18px;
}

.score-panel {
  min-width: 148px;
  padding: 14px 16px;
  text-align: center;
}

.score-label {
  display: block;
  color: var(--muted);
  margin-bottom: 6px;
  font-size: 0.92rem;
}

#score {
  font-size: clamp(1.75rem, 5vw, 2.5rem);
  color: #fff;
}

.info-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(260px, 320px);
  gap: 16px;
  margin-bottom: 18px;
}

.tips-card,
.action-card {
  padding: 16px;
}

h2 {
  margin: 0 0 12px;
  font-size: 1.05rem;
}

.tips-card ul {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
  line-height: 1.75;
  font-size: 0.95rem;
}

kbd {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 28px;
  padding: 3px 7px;
  margin-right: 5px;
  border-radius: 8px;
  border: 1px solid rgba(148, 163, 184, 0.22);
  background: rgba(30, 41, 59, 0.86);
  color: #fff;
  font-size: 0.85rem;
  font-weight: 700;
}

.button-group {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.btn {
  border: none;
  border-radius: 12px;
  padding: 10px 16px;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, opacity 0.2s ease, background 0.2s ease;
}

.btn:hover:not(:disabled) {
  transform: translateY(-1px);
}

.btn:active:not(:disabled) {
  transform: translateY(1px);
}

.btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.btn-primary {
  color: #06202a;
  background: linear-gradient(135deg, #67e8f9, var(--primary));
  box-shadow: 0 10px 24px rgba(14, 165, 233, 0.22);
}

.btn-secondary {
  color: #fff;
  background: linear-gradient(135deg, #1d4ed8, #2563eb);
}

.btn-ghost {
  color: #fff;
  background: rgba(30, 41, 59, 0.95);
  border: 1px solid rgba(148, 163, 184, 0.18);
}

.status-text {
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 0.94rem;
}

.board-section {
  display: flex;
  justify-content: center;
}

.board-frame {
  position: relative;
  touch-action: none;
  width: min(64vmin, 460px);
  aspect-ratio: 1 / 1;
  padding: 10px;
  border-radius: 24px;
  background: linear-gradient(180deg, rgba(15, 23, 42, 0.95), rgba(2, 6, 23, 0.98));
  border: 2px solid rgba(96, 165, 250, 0.42);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.06),
    0 0 0 1px rgba(147, 197, 253, 0.18),
    0 18px 36px rgba(2, 8, 23, 0.34);
  overflow: hidden;
}

.board-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  border-radius: inherit;
  box-shadow: inset 0 0 0 2px rgba(56, 189, 248, 0.18);
}

#game-canvas {
  width: 100%;
  height: 100%;
  display: block;
  border-radius: 16px;
  background: linear-gradient(180deg, #08101e, #050b16);
  border: 2px solid rgba(148, 163, 184, 0.22);
  box-shadow: inset 0 0 0 1px rgba(96, 165, 250, 0.08);
}

.overlay-message {
  position: absolute;
  inset: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 18px;
  border-radius: 16px;
  background: rgba(2, 6, 23, 0.52);
  color: #fff;
  font-weight: 800;
  font-size: clamp(1.1rem, 2.2vw, 1.8rem);
  letter-spacing: 0.04em;
  text-shadow: 0 0 20px rgba(56, 189, 248, 0.3);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

.overlay-message.show {
  opacity: 1;
}

.board-frame.paused .overlay-message {
  background: rgba(15, 23, 42, 0.58);
}

.board-frame.game-over {
  animation: shake 0.45s ease;
}

.board-frame.flash-eat {
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.05),
    0 0 0 1px rgba(52, 211, 153, 0.22),
    0 16px 34px rgba(16, 185, 129, 0.18);
}

.mobile-controls {
  width: min(260px, 100%);
  margin: 16px auto 0;
  padding: 12px;
  display: none;
}

.control-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin: 10px 0;
}

.control-btn {
  border: 1px solid rgba(148, 163, 184, 0.16);
  background: linear-gradient(180deg, rgba(30, 41, 59, 0.96), rgba(15, 23, 42, 0.96));
  color: #fff;
  border-radius: 16px;
  min-height: 54px;
  font-size: 1.35rem;
  font-weight: 800;
  cursor: pointer;
  touch-action: manipulation;
  user-select: none;
}

.control-btn:active {
  transform: scale(0.97);
}

.control-up,
.control-down {
  display: block;
  width: 72px;
  margin: 0 auto;
}

.control-center {
  color: var(--warning);
}

.modal {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: grid;
  place-items: center;
  padding: 20px;
  background: rgba(2, 6, 23, 0.78);
  backdrop-filter: blur(8px);
}

.modal.hidden {
  display: none;
}

.modal-card {
  width: min(400px, 100%);
  padding: 24px;
  border-radius: 24px;
  background: linear-gradient(180deg, rgba(15, 23, 42, 0.98), rgba(17, 24, 39, 0.98));
  border: 1px solid rgba(248, 113, 113, 0.24);
  box-shadow: 0 24px 70px rgba(2, 8, 23, 0.4);
  text-align: center;
}

.modal-tag {
  display: inline-flex;
  padding: 6px 12px;
  border-radius: 999px;
  color: #fff;
  background: rgba(248, 113, 113, 0.16);
  border: 1px solid rgba(248, 113, 113, 0.2);
  font-size: 0.82rem;
  font-weight: 700;
}

.modal-card h2 {
  margin: 14px 0 10px;
  font-size: 1.75rem;
}

.modal-score {
  margin: 0;
  font-size: 1.08rem;
}

.modal-score strong {
  color: var(--warning);
  font-size: 1.7rem;
}

.modal-text {
  color: var(--muted);
  line-height: 1.7;
}

.modal-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 16px;
}

@keyframes shake {
  0%,
  100% { transform: translateX(0); }
  25% { transform: translateX(-8px); }
  50% { transform: translateX(8px); }
  75% { transform: translateX(-5px); }
}



@media (min-width: 681px) and (max-width: 1180px) {
  .page-shell {
    align-items: flex-start;
    padding:
      max(20px, env(safe-area-inset-top))
      max(20px, env(safe-area-inset-right))
      max(calc(24px + env(safe-area-inset-bottom)), 24px)
      max(20px, env(safe-area-inset-left));
  }

  .game-card {
    width: min(920px, 100%);
    padding: 20px;
  }

  .hero-panel {
    gap: 18px;
  }

  .subtitle {
    max-width: 100%;
  }

  .info-grid {
    grid-template-columns: minmax(0, 1.15fr) minmax(280px, 0.85fr);
    gap: 14px;
  }

  .tips-card,
  .action-card {
    min-height: 100%;
  }

  .board-frame {
    width: min(66vw, 560px);
  }
}

@media (min-width: 681px) and (max-width: 1180px) and (pointer: coarse) {
  .button-group {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .btn {
    min-height: 48px;
  }

  .mobile-controls {
    display: block;
    width: min(360px, 100%);
    padding: 14px;
    margin-top: 18px;
  }

  .control-row {
    gap: 12px;
    margin: 12px 0;
  }

  .control-btn {
    min-height: 64px;
    border-radius: 18px;
    font-size: 1.55rem;
  }

  .control-up,
  .control-down {
    width: 86px;
  }
}

@media (min-width: 681px) and (max-width: 1180px) and (orientation: portrait) {
  .game-card {
    width: min(860px, 100%);
  }

  .hero-panel,
  .info-grid {
    display: grid;
    grid-template-columns: 1fr;
  }

  .score-panel {
    width: 100%;
  }

  .board-frame {
    width: min(72vw, 560px);
  }
}

@media (min-width: 681px) and (max-width: 1180px) and (orientation: landscape) {
  .page-shell {
    align-items: center;
  }

  .game-card {
    width: min(1080px, 100%);
  }

  .board-frame {
    width: min(52vw, 560px);
  }
}

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

  .hero-panel {
    gap: 14px;
  }

  .score-panel {
    width: 100%;
  }
}

@media (max-width: 680px) {
  .page-shell {
    align-items: flex-start;
    padding:
      max(12px, env(safe-area-inset-top))
      max(12px, env(safe-area-inset-right))
      max(calc(16px + env(safe-area-inset-bottom)), 16px)
      max(12px, env(safe-area-inset-left));
  }

  .game-card {
    width: 100%;
    padding: 14px;
    border-radius: 20px;
  }

  .hero-panel {
    margin-bottom: 14px;
  }

  .info-grid {
    gap: 12px;
    margin-bottom: 14px;
  }

  .tips-card,
  .action-card {
    padding: 14px;
  }

  .button-group {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .btn {
    min-height: 44px;
    padding: 10px 12px;
  }

  .board-frame {
    width: min(92vw, 400px);
    padding: 8px;
    border-radius: 20px;
  }

  .overlay-message {
    inset: 8px;
    border-radius: 14px;
  }

  .mobile-controls {
    display: block;
    width: min(280px, 100%);
    margin-top: 14px;
  }
}

@media (max-width: 680px) and (orientation: landscape) {
  .page-shell {
    align-items: center;
  }

  .game-card {
    max-width: 860px;
  }

  .board-frame {
    width: min(54vh, 78vw);
  }

  .mobile-controls {
    width: min(300px, 52vw);
  }
}

@media (max-width: 480px) {
  .page-shell {
    padding:
      max(10px, env(safe-area-inset-top))
      max(10px, env(safe-area-inset-right))
      max(calc(14px + env(safe-area-inset-bottom)), 14px)
      max(10px, env(safe-area-inset-left));
  }

  .game-card {
    width: 100%;
    padding: 12px;
    border-radius: 18px;
  }

  h1 {
    font-size: 1.45rem;
  }

  .subtitle,
  .tips-card ul,
  .status-text {
    font-size: 0.9rem;
  }

  .tips-card ul {
    line-height: 1.6;
  }

  .button-group,
  .modal-actions {
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }

  .board-frame {
    width: min(94vw, 360px);
    padding: 7px;
    border-radius: 18px;
  }

  .mobile-controls {
    width: min(248px, 100%);
    padding: 10px;
    margin-top: 14px;
  }

  .control-row {
    gap: 8px;
    margin: 8px 0;
  }

  .control-btn {
    min-height: 50px;
    border-radius: 14px;
    font-size: 1.15rem;
  }

  .control-up,
  .control-down {
    width: 64px;
  }

  .modal {
    padding:
      max(14px, env(safe-area-inset-top))
      max(14px, env(safe-area-inset-right))
      max(calc(18px + env(safe-area-inset-bottom)), 18px)
      max(14px, env(safe-area-inset-left));
  }

  .modal-card {
    padding: 20px;
    border-radius: 20px;
  }
}