* {
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

:root {
  --bg: #090b16;
  --panel: rgba(20, 24, 42, .86);
  --panel2: rgba(28, 33, 56, .72);
  --text: #f5f7ff;
  --muted: #8f98b5;
  --cyan: #00e5ff;
  --green: #6dff7a;
  --pink: #ff3d81;
  --orange: #ffb52e;
  --border: rgba(255,255,255,.09);
}

html, body {
  margin: 0;
  width: 100%;
  min-height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

body {
  min-height: 100vh;
  min-height: 100dvh;
  overflow-x: hidden;
  background:
    radial-gradient(circle at 15% 10%, rgba(0,229,255,.12), transparent 32%),
    radial-gradient(circle at 90% 75%, rgba(255,61,129,.10), transparent 35%),
    #090b16;
}

button {
  font: inherit;
  color: inherit;
  border: 0;
  cursor: pointer;
  user-select: none;
}

.app {
  width: min(100%, 520px);
  min-height: 100vh;
  min-height: 100dvh;
  margin: auto;
  padding: 18px 16px 24px;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 18px;
}

.eyebrow, .section-label {
  color: var(--cyan);
  font-size: 10px;
  font-weight: 900;
  letter-spacing: 2px;
}

h1 {
  margin: 2px 0 0;
  font-size: clamp(25px, 7vw, 34px);
  letter-spacing: 1px;
  line-height: 1;
}

h2 {
  margin: 5px 0;
  font-size: 32px;
}

.icon-btn, .small-btn {
  width: 44px;
  height: 44px;
  border-radius: 14px;
  background: var(--panel);
  border: 1px solid var(--border);
  transition: transform .15s, background .15s;
}

.icon-btn:active, .small-btn:active, .primary-btn:active,
.secondary-btn:active, .mode-btn:active, .dpad-btn:active {
  transform: scale(.95);
}

.screen {
  display: none;
  animation: appear .25s ease;
}

.screen.active {
  display: block;
}

@keyframes appear {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.snake-logo {
  font-size: 78px;
  text-align: center;
  margin: 8px 0 2px;
  filter: drop-shadow(0 0 18px rgba(0,229,255,.45));
  animation: float 2.8s ease-in-out infinite;
}

@keyframes float {
  50% { transform: translateY(-8px) rotate(2deg); }
}

.tagline {
  text-align: center;
  color: var(--muted);
  margin: 0 0 22px;
}

.mode-card, .settings-card {
  background: linear-gradient(145deg, var(--panel), var(--panel2));
  border: 1px solid var(--border);
  border-radius: 22px;
  padding: 16px;
  box-shadow: 0 18px 45px rgba(0,0,0,.22);
  backdrop-filter: blur(12px);
}

.mode-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 9px;
  margin-top: 11px;
}

.mode-btn {
  min-height: 88px;
  padding: 10px 6px;
  border-radius: 16px;
  background: rgba(255,255,255,.035);
  border: 1px solid transparent;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  transition: .2s;
}

.mode-btn span {
  font-size: 12px;
  margin-bottom: 2px;
}

.mode-btn strong { font-size: 14px; }
.mode-btn small { color: var(--muted); font-size: 10px; }

.mode-btn.easy span { color: var(--green); }
.mode-btn.medium span { color: var(--orange); }
.mode-btn.hard span { color: var(--pink); }

.mode-btn.selected {
  background: rgba(0,229,255,.10);
  border-color: rgba(0,229,255,.42);
  box-shadow: inset 0 0 18px rgba(0,229,255,.06);
}

.primary-btn, .secondary-btn {
  width: 100%;
  min-height: 54px;
  border-radius: 17px;
  margin-top: 16px;
  font-weight: 900;
  letter-spacing: .7px;
  transition: .15s;
}

.primary-btn {
  background: linear-gradient(100deg, #00bcd4, #00e5ff);
  color: #031015;
  box-shadow: 0 8px 25px rgba(0,229,255,.22);
}

.secondary-btn {
  background: rgba(255,255,255,.06);
  border: 1px solid var(--border);
}

.home-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  margin-top: 18px;
  gap: 10px;
}

.home-stats div {
  background: rgba(255,255,255,.035);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 12px;
}

.home-stats span, .final-score span, .game-info span {
  display: block;
  color: var(--muted);
  font-size: 9px;
  letter-spacing: 1.5px;
  font-weight: 800;
}

.home-stats strong {
  display: block;
  margin-top: 3px;
  font-size: 17px;
}

.game-info {
  display: grid;
  grid-template-columns: 44px 1fr 1fr 1fr 44px;
  gap: 7px;
  align-items: center;
  margin-bottom: 10px;
}

.game-info > div {
  text-align: center;
  background: rgba(255,255,255,.035);
  border: 1px solid var(--border);
  border-radius: 13px;
  padding: 7px 3px;
}

.game-info strong {
  display: block;
  margin-top: 2px;
  font-size: 14px;
}

.board-wrap {
  position: relative;
  width: 100%;
  aspect-ratio: 1;
  max-width: 500px;
  margin: 0 auto;
  border-radius: 22px;
  padding: 5px;
  background: linear-gradient(145deg, rgba(0,229,255,.45), rgba(255,61,129,.3));
  box-shadow: 0 0 35px rgba(0,229,255,.08);
  touch-action: none;
}

#gameCanvas {
  display: block;
  width: 100%;
  height: 100%;
  border-radius: 18px;
  background: #080d15;
  touch-action: none;
}

.control-hint {
  text-align: center;
  color: var(--muted);
  font-size: 11px;
  margin: 12px 0 4px;
}

.dpad {
  position: relative;
  width: 180px;
  height: 150px;
  margin: 8px auto 0;
}

.dpad.hidden { display: none; }

.dpad-btn {
  position: absolute;
  width: 55px;
  height: 55px;
  border-radius: 17px;
  background: linear-gradient(145deg, #1d2540, #11162a);
  border: 1px solid rgba(255,255,255,.10);
  box-shadow: 0 7px 15px rgba(0,0,0,.25);
  color: var(--cyan);
  font-size: 18px;
}

.dpad-btn.up { left: 62px; top: 0; }
.dpad-btn.left { left: 0; top: 55px; }
.dpad-btn.down { left: 62px; top: 55px; }
.dpad-btn.right { right: 0; top: 55px; }

.overlay {
  position: absolute;
  inset: 5px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 18px;
  background: rgba(4,7,15,.78);
  backdrop-filter: blur(5px);
}

.overlay.hidden { display: none; }

.overlay-card {
  width: min(80%, 290px);
  padding: 24px;
  text-align: center;
  border-radius: 22px;
  background: rgba(20,24,42,.96);
  border: 1px solid var(--border);
}

.overlay-icon { font-size: 36px; color: var(--cyan); }

.gameover-icon {
  text-align: center;
  font-size: 64px;
  margin-top: 32px;
  filter: drop-shadow(0 0 16px rgba(255,61,129,.4));
}

#gameOverScreen { text-align: center; }

#gameOverScreen h2 {
  font-size: 38px;
  margin-top: 4px;
}

.final-score {
  margin: 25px auto 12px;
  padding: 18px;
  width: min(90%, 300px);
  border-radius: 20px;
  background: var(--panel);
  border: 1px solid var(--border);
}

.final-score strong {
  display: block;
  font-size: 50px;
  margin-top: 2px;
}

.new-best {
  color: var(--orange);
  font-weight: 900;
  animation: pulse 1s infinite alternate;
}

.new-best.hidden { display: none; }

@keyframes pulse {
  to { transform: scale(1.04); }
}

.settings-head {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
}

.settings-head h2 { font-size: 25px; }

.setting-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 15px;
  padding: 17px 0;
  border-bottom: 1px solid var(--border);
}

.setting-row:last-child { border-bottom: 0; }

.setting-row strong { display: block; font-size: 15px; }
.setting-row small { display: block; color: var(--muted); margin-top: 4px; font-size: 11px; }

.setting-row.stack { display: block; }

.toggle {
  width: 53px;
  height: 31px;
  padding: 3px;
  border-radius: 99px;
  background: #30364d;
}

.toggle span {
  display: block;
  width: 25px;
  height: 25px;
  border-radius: 50%;
  background: #fff;
  transition: .2s;
}

.toggle.on { background: var(--cyan); }
.toggle.on span { transform: translateX(22px); }

.control-options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-top: 12px;
}

.control-option, .danger-btn {
  border-radius: 13px;
  background: rgba(255,255,255,.05);
  border: 1px solid var(--border);
  padding: 12px 8px;
  font-size: 11px;
  font-weight: 800;
}

.control-option.selected {
  border-color: rgba(0,229,255,.5);
  background: rgba(0,229,255,.10);
  color: var(--cyan);
}

.danger-btn {
  color: #ff6b91;
}

.about {
  text-align: center;
  margin-top: 25px;
  color: var(--muted);
  font-size: 11px;
}

.about strong, .about span { display: block; }
.about span { margin-top: 4px; }

@media (min-height: 800px) {
  .app { padding-top: 25px; }
  .snake-logo { margin-top: 28px; }
}

@media (max-height: 650px) {
  .snake-logo { font-size: 54px; margin: 0; }
  .tagline { margin-bottom: 12px; }
  .mode-btn { min-height: 70px; }
  .primary-btn { margin-top: 10px; }
}


.site-footer {
  margin-top: 30px;
  padding: 13px 8px 4px;
  text-align: center;
  color: var(--muted);
  font-size: 11px;
  line-height: 1.7;
  border-top: 1px solid rgba(255,255,255,.06);
}

.site-footer .footer-title {
  margin-bottom: 2px;
  font-size: 12px;
}

.site-footer .footer-title strong {
  color: var(--cyan);
  font-weight: 800;
}

.site-footer .footer-title span {
  color: var(--muted);
}

@media (max-height: 650px) {
  .site-footer { margin-top: 18px; }
}