:root {
  --card: rgba(8, 20, 28, 0.8);
  --line: #2e687a;
  --line-strong: #4ea9c0;
  --x: #ff9157;
  --o: #7bd389;
  --text-main: #e8f3f7;
  --text-soft: #aac6cf;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Space Grotesk", "Trebuchet MS", sans-serif;
  color: var(--text-main);
  background:
    radial-gradient(circle at 15% 20%, rgba(145, 205, 255, 0.34), transparent 36%),
    radial-gradient(circle at 85% 80%, rgba(112, 186, 255, 0.3), transparent 34%),
    linear-gradient(145deg, #2b6fa7, #57a7e6);
  transition: background 0.32s ease;
}

body.turn-human {
  background:
    radial-gradient(circle at 15% 20%, rgba(145, 205, 255, 0.34), transparent 36%),
    radial-gradient(circle at 85% 80%, rgba(112, 186, 255, 0.3), transparent 34%),
    linear-gradient(145deg, #2b6fa7, #57a7e6);
}

body.turn-ai {
  background:
    radial-gradient(circle at 15% 20%, rgba(255, 184, 184, 0.34), transparent 36%),
    radial-gradient(circle at 85% 80%, rgba(255, 145, 145, 0.3), transparent 34%),
    linear-gradient(145deg, #a94148, #e47c83);
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.2;
  background-image: linear-gradient(rgba(255, 255, 255, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.06) 1px, transparent 1px);
  background-size: 32px 32px;
}

.app {
  max-width: 1180px;
  margin: 0 auto;
  padding: 20px 16px 26px;
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
}

.panel {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 12px 14px;
  backdrop-filter: blur(4px);
}

.control-rail {
  position: sticky;
  top: 12px;
  display: grid;
  gap: 12px;
}

.rail-group {
  display: grid;
  gap: 8px;
}

h1 {
  margin: 0;
  font-size: clamp(1.25rem, 1.1rem + 0.6vw, 1.65rem);
  line-height: 1.1;
}

.subtitle {
  margin: 4px 0 0;
  color: var(--text-soft);
  font-size: 0.92rem;
}

.setting-label {
  margin: 0;
  font-size: 0.86rem;
  font-weight: 700;
  color: #d3eaf2;
}

.hidden {
  display: none !important;
}

.modes,
.difficulty-buttons,
.online-actions,
.share-channels {
  display: grid;
  gap: 8px;
}

.mode-btn,
.primary-btn {
  border: 1px solid var(--line);
  background: #173748;
  color: var(--text-main);
  font: inherit;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: 10px;
  padding: 10px 12px;
  cursor: pointer;
  transition: transform 0.18s ease, border-color 0.2s ease, background 0.2s ease;
}

.control-rail .mode-btn,
.control-rail .primary-btn,
.control-rail .room-code-input {
  width: 100%;
}

.mode-btn:hover,
.primary-btn:hover {
  transform: translateY(-1px);
  border-color: var(--line-strong);
}

.mode-btn.active {
  background: linear-gradient(135deg, #204e63, #1a414f);
  border-color: var(--line-strong);
}

.online-panel {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 10px;
  background: rgba(13, 36, 50, 0.56);
}

.room-code-input {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 9px 10px;
  background: rgba(9, 25, 35, 0.72);
  color: var(--text-main);
  font: inherit;
  font-size: 0.9rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.room-code-input:focus {
  outline: 2px solid rgba(142, 210, 245, 0.55);
  outline-offset: 1px;
}

.online-room-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.online-room-code {
  margin: 0;
  color: #d5ecf7;
  font-size: 0.86rem;
  font-weight: 700;
}

.room-copy-btn {
  width: auto;
  padding: 8px 10px;
  font-size: 0.84rem;
}

.online-meta {
  margin: 0;
  color: #c4e4f0;
  font-size: 0.84rem;
}

.online-meta.error {
  color: #ffd8d8;
}

.difficulty-note {
  margin: 0;
  color: var(--text-soft);
  font-size: 0.84rem;
}

.music-controls {
  align-items: center;
}

.music-btn.active {
  border-color: #8ed2f5;
  background: linear-gradient(135deg, #2f7da3, #2d6e91);
}

.music-status {
  margin: 0;
  color: #d4ecf8;
  font-size: 0.86rem;
}

.invite-title {
  margin: 0;
  font-size: 1rem;
}

.invite-subtitle {
  margin: 4px 0 0;
  color: var(--text-soft);
  font-size: 0.86rem;
}

.share-menu {
  display: grid;
  gap: 8px;
}

.share-channels {
  max-height: 0;
  opacity: 0;
  overflow: hidden;
  transform: translateY(-4px);
  pointer-events: none;
  transition: max-height 0.22s ease, opacity 0.2s ease, transform 0.2s ease;
}

.share-menu:hover .share-channels,
.share-menu:focus-within .share-channels {
  max-height: 320px;
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.qr-wrap {
  margin-top: 4px;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 10px;
  background: rgba(14, 35, 47, 0.62);
  display: grid;
  justify-items: center;
  gap: 8px;
}

.qr-label {
  margin: 0;
  font-size: 0.82rem;
  color: #d4ebf6;
  font-weight: 700;
}

.invite-qr-image {
  width: 124px;
  height: 124px;
  border-radius: 10px;
  border: 1px solid rgba(197, 225, 237, 0.55);
  background: #ffffff;
}

.invite-qr-link {
  color: #b8e5ff;
  text-decoration: none;
  font-size: 0.74rem;
  text-align: center;
  word-break: break-all;
}

.invite-qr-link:hover {
  text-decoration: underline;
}

.invite-feedback {
  min-height: 1em;
  margin: 2px 0 0;
  color: #d0e7ee;
  font-size: 0.84rem;
}

.invite-feedback.error {
  color: #ffd3d3;
}

.status-hidden {
  display: none;
}

.youtube-audio-host {
  position: fixed;
  width: 0;
  height: 0;
  overflow: hidden;
  opacity: 0;
  pointer-events: none;
}

.youtube-audio-host iframe {
  width: 0;
  height: 0;
  border: 0;
}

.celebration-overlay {
  --celebration-main: #ff9157;
  --celebration-soft: #ffd0b4;
  --celebration-glow-a: rgba(255, 145, 87, 0.36);
  --celebration-glow-b: rgba(255, 145, 87, 0.22);
  --celebration-glow-c: rgba(255, 145, 87, 0.18);
  --celebration-shadow-a: rgba(255, 145, 87, 0.55);
  --celebration-shadow-b: rgba(255, 145, 87, 0.45);
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0;
  transform: scale(1.02);
  transition: opacity 0.35s ease, transform 0.35s ease;
  z-index: 30;
}

.celebration-overlay.active {
  opacity: 1;
  transform: scale(1);
}

.celebration-overlay.winner-x {
  --celebration-main: #ff9157;
  --celebration-soft: #ffd0b4;
}

.celebration-overlay.winner-o {
  --celebration-main: #7bd389;
  --celebration-soft: #d7ffe4;
  --celebration-glow-a: rgba(123, 211, 137, 0.36);
  --celebration-glow-b: rgba(123, 211, 137, 0.22);
  --celebration-glow-c: rgba(123, 211, 137, 0.18);
  --celebration-shadow-a: rgba(123, 211, 137, 0.55);
  --celebration-shadow-b: rgba(123, 211, 137, 0.45);
}

.celebration-glow {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 50% 45%, var(--celebration-glow-a), transparent 52%),
    radial-gradient(circle at 20% 20%, var(--celebration-glow-b), transparent 38%),
    radial-gradient(circle at 80% 20%, var(--celebration-glow-c), transparent 36%);
  animation: celebration-pulse 1.05s ease-in-out infinite;
}

.celebration-content {
  position: absolute;
  inset: 0;
  display: grid;
  place-content: center;
  text-align: center;
  gap: 8px;
  animation: celebration-pop 0.6s ease-out both;
}

.celebration-label {
  margin: 0;
  font-size: 0.96rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--celebration-soft);
}

.celebration-title {
  margin: 0;
  font-size: clamp(2rem, 1.6rem + 2.3vw, 4rem);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--celebration-main);
  text-shadow:
    0 0 18px var(--celebration-shadow-a),
    0 0 42px var(--celebration-shadow-b);
}

.celebration-confetti {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.confetti-piece {
  position: absolute;
  top: -8%;
  width: 10px;
  height: 18px;
  border-radius: 2px;
  background: var(--confetti-color, var(--celebration-main));
  opacity: 0.95;
  transform: translateY(-10vh) rotate(0deg);
  animation: confetti-fall var(--fall-duration, 2800ms) linear forwards;
}

.arena {
  display: grid;
  grid-template-columns: minmax(120px, 145px) minmax(0, 1fr);
  align-items: start;
  gap: 10px;
}

.score-stack {
  display: grid;
  gap: 10px;
}

.side-score {
  text-align: center;
  padding: 10px 8px;
  display: grid;
  gap: 3px;
}

.side-score-player .side-value {
  color: var(--x);
}

.side-score-opponent .side-value {
  color: var(--o);
}

.side-label {
  margin: 0;
  font-size: 0.82rem;
  color: var(--text-soft);
  font-weight: 700;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.side-value {
  margin: 0;
  font-size: clamp(1.6rem, 1.45rem + 0.75vw, 2.1rem);
  font-weight: 700;
  line-height: 1;
}

.side-sub {
  margin: 0;
  font-size: 0.74rem;
  color: var(--text-soft);
}

.draw-chip {
  margin-top: 4px;
  border: 1px solid var(--line);
  border-radius: 9px;
  padding: 5px 7px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.74rem;
  color: #d7e7ed;
  background: rgba(21, 43, 54, 0.75);
}

.board-wrap {
  width: 100%;
  overflow-x: auto;
  padding-bottom: 4px;
}

.ultimate-board {
  width: min(100%, 580px);
  min-width: 300px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 6px;
}

.mini-board {
  position: relative;
  background: rgba(13, 31, 42, 0.85);
  border: 2px solid var(--line);
  border-radius: 10px;
  padding: 5px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 5px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease, opacity 0.2s ease;
}

.mini-board.active {
  border-color: var(--line-strong);
  box-shadow: 0 0 0 2px rgba(78, 169, 192, 0.18);
}

.mini-board.inactive {
  opacity: 0.5;
}

.mini-board.won-x,
.mini-board.won-o,
.mini-board.tied {
  opacity: 1;
}

.mini-board.won-x {
  border-color: #ffc09a;
  background:
    linear-gradient(140deg, rgba(255, 145, 87, 0.2), rgba(255, 145, 87, 0.08)),
    rgba(13, 31, 42, 0.9);
  box-shadow: 0 0 0 2px rgba(255, 145, 87, 0.24);
}

.mini-board.won-o {
  border-color: #ade7b8;
  background:
    linear-gradient(140deg, rgba(123, 211, 137, 0.2), rgba(123, 211, 137, 0.08)),
    rgba(13, 31, 42, 0.9);
  box-shadow: 0 0 0 2px rgba(123, 211, 137, 0.24);
}

.mini-board.tied {
  border-color: rgba(194, 213, 222, 0.6);
  background:
    linear-gradient(140deg, rgba(194, 213, 222, 0.14), rgba(194, 213, 222, 0.05)),
    rgba(13, 31, 42, 0.9);
}

.mini-board.won-x .cell {
  border-color: rgba(255, 145, 87, 0.35);
  background: rgba(68, 35, 24, 0.45);
}

.mini-board.won-o .cell {
  border-color: rgba(123, 211, 137, 0.35);
  background: rgba(25, 58, 39, 0.45);
}

.mini-board.just-won {
  animation: mini-win-burst 0.5s ease-out;
}

.cell {
  border: 1px solid var(--line);
  border-radius: 7px;
  background: rgba(23, 55, 68, 0.72);
  aspect-ratio: 1 / 1;
  width: 100%;
  display: grid;
  place-items: center;
  font: inherit;
  font-size: clamp(1rem, 0.64rem + 1.5vw, 1.5rem);
  font-weight: 700;
  color: var(--text-main);
  padding: 0;
  cursor: pointer;
  transition: background 0.2s ease, transform 0.12s ease;
}

.cell:not(:disabled):hover {
  transform: scale(1.03);
  background: rgba(42, 90, 109, 0.86);
}

.cell:disabled {
  cursor: default;
}

.cell.x {
  color: var(--x);
}

.cell.o {
  color: var(--o);
}

.mini-overlay {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: clamp(1.1rem, 0.9rem + 0.8vw, 1.55rem);
  border-radius: 8px;
  pointer-events: none;
  animation: stamp-in 0.28s ease-out both;
}

.mini-overlay.x {
  color: var(--x);
  background: rgba(255, 145, 87, 0.12);
}

.mini-overlay.o {
  color: var(--o);
  background: rgba(123, 211, 137, 0.12);
}

.mini-overlay.t {
  color: #bfd6dd;
  background: rgba(190, 205, 212, 0.1);
}

@keyframes mini-win-burst {
  0% {
    transform: scale(1);
  }
  35% {
    transform: scale(1.03);
  }
  100% {
    transform: scale(1);
  }
}

@keyframes stamp-in {
  from {
    opacity: 0;
    transform: scale(0.7);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

@keyframes celebration-pop {
  from {
    opacity: 0;
    transform: scale(0.88);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

@keyframes celebration-pulse {
  0% {
    opacity: 0.72;
  }
  50% {
    opacity: 1;
  }
  100% {
    opacity: 0.72;
  }
}

@keyframes confetti-fall {
  0% {
    transform: translate3d(0, -12vh, 0) rotate(0deg);
  }
  100% {
    transform: translate3d(var(--drift-x, 0px), 108vh, 0) rotate(var(--spin, 520deg));
  }
}

@media (max-width: 960px) {
  .app {
    grid-template-columns: 1fr;
  }

  .control-rail {
    position: static;
  }

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

  .score-stack {
    gap: 8px;
  }

  .side-score {
    text-align: left;
    grid-template-columns: auto 1fr auto;
    align-items: center;
    gap: 8px;
  }

  .side-sub {
    justify-self: end;
  }

  .draw-chip {
    grid-column: 1 / -1;
  }
}