:root {
  --bg: #050806;
  --bg-2: #09130d;
  --panel: rgba(5, 14, 9, .88);
  --panel-2: rgba(12, 29, 17, .86);
  --ink: #effff1;
  --muted: #9cc9a6;
  --dim: #66856d;
  --line: rgba(173, 255, 184, .17);
  --line-strong: rgba(173, 255, 184, .32);
  --snake: #7dff8d;
  --snake-dark: #2cbf5f;
  --food: #ff3f58;
  --cyan: #31e6d0;
  --yellow: #f4e35d;
  --shadow: 0 20px 60px rgba(0, 0, 0, .48);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  color: var(--ink);
  font-family: "Trebuchet MS", system-ui, sans-serif;
  background:
    linear-gradient(rgba(125, 255, 141, .035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(49, 230, 208, .035) 1px, transparent 1px),
    linear-gradient(145deg, var(--bg), var(--bg-2) 58%, #101405);
  background-size: 32px 32px, 32px 32px, auto;
  overflow-x: hidden;
}

body::after {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background: repeating-linear-gradient(to bottom, rgba(255,255,255,.04), rgba(255,255,255,.04) 1px, transparent 1px, transparent 4px);
  mix-blend-mode: soft-light;
  opacity: .36;
  z-index: 30;
}

button,
input {
  font: inherit;
}

.home-link {
  position: fixed;
  top: 1rem;
  left: 1rem;
  z-index: 40;
  color: var(--ink);
  text-decoration: none;
  border: 1px solid var(--line);
  background: rgba(0, 0, 0, .45);
  padding: .55rem .75rem;
  border-radius: 6px;
  backdrop-filter: blur(10px);
}

.home-link:hover {
  border-color: var(--cyan);
  color: var(--cyan);
}

.shell {
  width: min(1180px, calc(100vw - 2rem));
  min-height: 100vh;
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(320px, 660px) minmax(280px, 360px);
  gap: 1rem;
  align-items: center;
  padding: 4rem 0 2rem;
}

.stage,
.panel {
  position: relative;
  z-index: 1;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
}

.stage {
  padding: .8rem;
}

.marquee {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  min-height: 4rem;
  margin-bottom: .8rem;
  padding: .75rem .9rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: linear-gradient(90deg, rgba(125,255,141,.12), rgba(49,230,208,.04));
}

.eyebrow {
  margin: 0 0 .25rem;
  color: var(--cyan);
  font-size: .72rem;
  font-weight: 900;
  letter-spacing: .12em;
  text-transform: uppercase;
}

.marquee h1 {
  margin: 0;
  color: var(--yellow);
  font-size: clamp(2rem, 6vw, 4.2rem);
  line-height: 1;
  letter-spacing: .03em;
  text-shadow: 0 0 16px rgba(244, 227, 93, .45);
}

#stateBadge {
  min-width: 6.5rem;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  padding: .45rem .7rem;
  color: var(--snake);
  background: rgba(0, 0, 0, .32);
  text-align: center;
  font-weight: 900;
  text-transform: uppercase;
}

.board-wrap {
  position: relative;
  width: min(100%, 576px);
  aspect-ratio: 1;
  margin: 0 auto;
}

#board {
  display: block;
  width: 100%;
  height: 100%;
  border: 2px solid var(--line-strong);
  border-radius: 6px;
  background: #020503;
  box-shadow: inset 0 0 34px rgba(0, 0, 0, .78), 0 0 34px rgba(125, 255, 141, .16);
  image-rendering: pixelated;
  touch-action: none;
}

.overlay {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  padding: 1rem;
  background: rgba(0, 0, 0, .58);
  border-radius: 6px;
}

.overlay.hidden {
  display: none;
}

.overlay-panel {
  width: min(92%, 360px);
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  background: rgba(2, 7, 4, .94);
  padding: 1.1rem;
  text-align: center;
  box-shadow: 0 18px 55px rgba(0,0,0,.55);
}

.overline {
  margin: 0 0 .35rem;
  color: var(--cyan);
  text-transform: uppercase;
  font-size: .76rem;
  font-weight: 900;
  letter-spacing: .14em;
}

.overlay-panel h2 {
  margin: 0;
  color: var(--yellow);
  font-size: 2.1rem;
}

.overlay-panel p {
  color: var(--muted);
}

.overlay-panel button,
.score-entry button {
  border: 0;
  border-radius: 6px;
  background: linear-gradient(90deg, var(--snake), var(--cyan));
  color: #031106;
  cursor: pointer;
  font-weight: 900;
  padding: .8rem 1rem;
  text-transform: uppercase;
}

.overlay-panel button:hover,
.score-entry button:hover {
  filter: brightness(1.08);
}

.score-entry {
  display: grid;
  gap: .55rem;
  margin: .85rem 0;
}

.score-entry.hidden {
  display: none;
}

.score-entry label {
  color: var(--ink);
  font-weight: 700;
}

.score-entry input {
  width: 6rem;
  margin: 0 auto;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #07120a;
  color: var(--ink);
  padding: .65rem;
  text-align: center;
  text-transform: uppercase;
  font: 900 1.2rem "Courier New", monospace;
}

.panel {
  padding: .85rem;
}

.meters {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: .5rem;
}

.meter,
.settings,
.scores-box,
.controls,
.perf {
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--panel-2);
}

.meter {
  min-height: 64px;
  padding: .6rem .7rem;
}

.meter span,
.settings h2,
.scores-box h2,
.controls h2,
.perf h2 {
  display: block;
  margin: 0 0 .35rem;
  color: var(--muted);
  font-size: .78rem;
  text-transform: uppercase;
  letter-spacing: .09em;
}

.meter strong {
  color: var(--ink);
  font-size: 1.55rem;
}

.settings,
.scores-box,
.controls,
.perf {
  margin-top: .6rem;
  padding: .7rem;
}

.segmented {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: .35rem;
}

.difficulty {
  min-height: 40px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: rgba(0, 0, 0, .28);
  color: var(--ink);
  cursor: pointer;
  font-weight: 900;
}

.difficulty.active {
  border-color: var(--cyan);
  color: #031106;
  background: linear-gradient(90deg, var(--snake), var(--cyan));
}

.toggle-row {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: .6rem;
  margin-top: .7rem;
  padding-top: .7rem;
  border-top: 1px solid var(--line);
  color: var(--ink);
  cursor: pointer;
}

.toggle-row input {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

.switch {
  position: relative;
  flex: 0 0 auto;
  width: 38px;
  height: 22px;
  border-radius: 999px;
  background: rgba(255,255,255,.14);
  border: 1px solid var(--line);
  transition: background .15s ease, border-color .15s ease;
}

.switch::after {
  content: "";
  position: absolute;
  top: 2px;
  left: 2px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--muted);
  transition: transform .15s ease, background .15s ease;
}

input:checked + .switch {
  background: rgba(49, 230, 208, .34);
  border-color: var(--cyan);
}

input:checked + .switch::after {
  transform: translateX(16px);
  background: var(--cyan);
}

input:focus-visible + .switch,
button:focus-visible,
a:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

.score-list {
  list-style-position: inside;
  margin: 0;
  padding: 0;
  display: grid;
  gap: .22rem;
  max-height: 128px;
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--cyan) transparent;
}

.score-list::-webkit-scrollbar {
  width: 6px;
}

.score-list::-webkit-scrollbar-thumb {
  background: var(--cyan);
  border-radius: 999px;
}

.score-list li {
  color: var(--ink);
  font-family: "Courier New", monospace;
  font-size: .9rem;
}

.score-list span {
  color: var(--cyan);
  font-weight: 900;
}

.controls p,
.perf p {
  margin: .26rem 0;
  color: var(--muted);
  font-size: .88rem;
}

.controls b {
  color: var(--ink);
}

.perf p {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
}

.perf strong {
  color: var(--snake);
}

.touch-controls {
  position: fixed;
  left: 50%;
  bottom: .75rem;
  z-index: 25;
  width: min(96vw, 420px);
  transform: translateX(-50%);
  display: none;
  grid-template-columns: repeat(4, 1fr);
  gap: .4rem;
}

.touch-controls button {
  min-height: 48px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: rgba(0, 0, 0, .66);
  color: var(--ink);
  cursor: pointer;
  font-size: 1.25rem;
  font-weight: 900;
  backdrop-filter: blur(10px);
}

@media (max-width: 920px) {
  .shell {
    grid-template-columns: 1fr;
    align-items: start;
    padding-top: 4rem;
  }

  .panel {
    margin-bottom: 4.6rem;
  }

  .touch-controls {
    display: grid;
  }
}

@media (max-width: 520px) {
  .shell {
    width: min(100vw - 1rem, 1180px);
  }

  .marquee {
    align-items: flex-start;
    flex-direction: column;
  }

  #stateBadge {
    min-width: 0;
  }

  .segmented {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
}