:root {
  --bg: #060606;
  --panel: #131313;
  --panel-strong: #161616;
  --text: #ffffff;
  --text-dim: #9a9a9a;
  --border: #2a2a2a;
  --border-strong: #3d3d3d;
}

* { box-sizing: border-box; }

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

.topbar {
  text-align: center;
  padding: 1.4rem 1rem 0.9rem;
  position: relative;
  z-index: 3;
  background: #000;
  color: #fff;
}

.topbar h1 {
  margin: 0;
  font-size: 2.1rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #fff;
}

.topbar h1 .or {
  color: var(--text-dim);
  font-weight: 500;
  font-style: italic;
  margin: 0 0.15em;
}

.subtitle {
  margin: 0.3rem 0 1rem;
  color: #fff;
  font-size: 0.9rem;
}

.mode-select {
  display: inline-flex;
  gap: 0.3rem;
  padding: 0.3rem;
  margin-bottom: 0.9rem;
  border-radius: 8px;
  background: var(--panel);
  border: 1px solid var(--border);
}

.mode-btn {
  border: none;
  background: transparent;
  color: var(--text-dim);
  font-family: inherit;
  font-weight: 600;
  font-size: 0.8rem;
  padding: 0.4rem 1rem;
  border-radius: 6px;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease;
}

.mode-btn:hover:not(.active):not(:disabled) {
  color: #fff;
  background: rgba(255, 255, 255, 0.06);
}

.mode-btn.active {
  color: #000;
  background: #fff;
}

.mode-btn:disabled { opacity: 0.5; cursor: default; }

.topbar-controls {
  display: contents;
}

.best-score {
  position: fixed;
  top: 1.4rem;
  left: 1.4rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.9rem;
  border-radius: 8px;
  background: var(--panel);
  border: 1px solid var(--border);
  z-index: 4;
}

.best-label {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
}

.best-value {
  font-size: 1rem;
  font-weight: 800;
  color: #fff;
}

.volume-control {
  position: fixed;
  top: 1.4rem;
  right: 1.4rem;
  display: flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.5rem 0.9rem;
  border-radius: 8px;
  background: var(--panel);
  border: 1px solid var(--border);
  z-index: 4;
}

.volume-label {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
}

.volume-control input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 90px;
  height: 4px;
  border-radius: 2px;
  background: linear-gradient(90deg, #fff, #fff 50%, var(--border) 50%);
  cursor: pointer;
}

.volume-control input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--text);
  cursor: pointer;
}

.volume-control input[type="range"]::-moz-range-thumb {
  width: 14px;
  height: 14px;
  border: none;
  border-radius: 50%;
  background: var(--text);
  cursor: pointer;
}

.stats {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.15rem;
  padding: 0.5rem 1.3rem;
  border-radius: 8px;
  background: var(--panel);
  border: 1px solid var(--border);
}

.stat-label {
  font-size: 0.65rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #fff;
}

.stat-value {
  font-size: 1.5rem;
  font-weight: 800;
  color: #fff;
}

.stat-btn {
  border: 1px solid var(--border);
  cursor: pointer;
  font-family: inherit;
  transition: border-color 0.15s ease, background 0.15s ease;
}

.stat-btn:hover {
  border-color: var(--border-strong);
  background: #1c1c1c;
}

.stat-btn .stat-value {
  font-size: 1.3rem;
}

/* Join / display-name gate */
.join-panel {
  gap: 0.6rem;
}

.join-panel h2 {
  font-size: 1.4rem;
  margin: 0;
}

.join-hint {
  color: var(--text-dim);
  font-size: 0.85rem;
  margin: 0 0 0.4rem;
}

.join-input {
  width: 100%;
  background: #000;
  border: 1px solid var(--border-strong);
  border-radius: 6px;
  padding: 0.7rem 0.9rem;
  color: #fff;
  font-family: inherit;
  font-size: 0.95rem;
  text-align: center;
}

.join-input:focus {
  outline: none;
  border-color: #fff;
}

.join-input::placeholder {
  color: var(--text-dim);
}

/* Game-over actions */
.gameover-actions {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  width: 100%;
}

.secondary-btn {
  padding: 0.7rem 2.2rem;
  border-radius: 6px;
  border: 1px solid var(--border-strong);
  background: transparent;
  color: #fff;
  font-weight: 700;
  font-size: 0.9rem;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease;
}

.secondary-btn:hover {
  background: #1c1c1c;
  border-color: #fff;
}

/* Ad slot */
.ad-tag {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-dim);
  margin: 0;
}

#frame {
  min-height: 90px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #0d0d0d;
  padding: 0.75rem;
}

#ad-countdown {
  font-weight: 800;
  color: #fff;
}

.ad-hint {
  color: var(--text-dim);
  font-size: 0.8rem;
  margin: 0;
}

/* Leaderboard */
.leaderboard-panel {
  width: 100%;
  max-width: 420px;
}

.leaderboard-list {
  width: 100%;
  list-style: none;
  margin: 0;
  padding: 0;
  max-height: 320px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.leaderboard-list li {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  padding: 0.55rem 0.8rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: #0d0d0d;
}

.leaderboard-rank {
  color: var(--text-dim);
  font-weight: 700;
  width: 1.6rem;
  flex-shrink: 0;
}

.leaderboard-name {
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-weight: 600;
}

.leaderboard-mode {
  color: var(--text-dim);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.leaderboard-score {
  font-weight: 800;
  color: #fff;
}

.leaderboard-empty {
  color: var(--text-dim);
  font-size: 0.9rem;
  padding: 1rem 0;
}

.board {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: stretch;
  gap: 0;
  height: calc(100vh - 172px);
  padding: 0 0 1rem;
}

.card {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.85rem;
  padding: 1.5rem;
  background-size: cover;
  background-position: center;
  overflow: hidden;
  transition: filter 0.35s ease;
}

.card::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(0, 0, 0, 0.6) 0%, rgba(0, 0, 0, 0.9) 70%, rgba(0, 0, 0, 0.98) 100%);
}

.card::after {
  content: "";
  position: absolute;
  inset: 0;
  box-shadow: inset 0 0 120px rgba(0, 0, 0, 0.6);
  pointer-events: none;
}

.card > * {
  position: relative;
  z-index: 1;
}

.card-art {
  width: 200px;
  height: 200px;
  border-radius: 10px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.6);
  object-fit: cover;
}

.card-title {
  font-size: 1.3rem;
  font-weight: 700;
  text-align: center;
  max-width: 380px;
  letter-spacing: -0.01em;
}

.card-artist {
  color: var(--text-dim);
  font-size: 0.95rem;
  text-align: center;
}

.card-rank {
  margin-top: 0.4rem;
  font-size: 2.6rem;
  font-weight: 800;
  color: #fff;
  min-height: 3.2rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.card-rank .rank-label {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  color: var(--text-dim);
  letter-spacing: 0.08em;
}

.card-rank.hidden-value {
  font-size: 2rem;
  font-weight: 700;
  color: var(--text-dim);
}

.play-btn {
  border: 1px solid var(--border-strong);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  border-radius: 6px;
  padding: 0.55rem 1.2rem;
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease;
}

.play-btn:hover { background: rgba(255, 255, 255, 0.1); }
.play-btn.playing {
  color: #000;
  background: #fff;
  border-color: #fff;
}

.card.correct { filter: brightness(1.1); }
.card.wrong { filter: grayscale(0.7) brightness(0.6); }

.vs {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1.4rem;
  padding: 0 1.6rem;
  z-index: 2;
}

.vs-label {
  font-size: 0.8rem;
  font-weight: 800;
  color: var(--text-dim);
  letter-spacing: 0.12em;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--panel);
  border: 1px solid var(--border-strong);
}

.guess-buttons {
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

.guess-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
  width: 100px;
  padding: 1rem 0.5rem;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text);
  font-weight: 700;
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  cursor: pointer;
  transition: border-color 0.15s ease, background 0.15s ease;
}

.guess-btn .arrow {
  font-size: 1.5rem;
  line-height: 1;
  color: #fff;
}

.guess-btn:hover:not(:disabled) {
  border-color: var(--border-strong);
  background: #1c1c1c;
}

.guess-btn:disabled { opacity: 0.35; cursor: default; }

.overlay[hidden] {
  display: none;
}

.overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.8);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
  padding: 2rem;
}

.panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  text-align: center;
  background: var(--panel-strong);
  border: 1px solid var(--border-strong);
  border-radius: 10px;
  padding: 2.5rem;
  max-width: 380px;
}

.overlay h2 {
  font-size: 1.8rem;
  margin: 0;
  color: #fff;
}

.overlay p { margin: 0; }

.final-score {
  font-size: 1.3rem;
}

.final-score span {
  font-weight: 800;
  color: #fff;
}

.final-best {
  color: var(--text-dim);
  min-height: 1.2rem;
  font-size: 0.9rem;
}

.primary-btn {
  margin-top: 0.4rem;
  padding: 0.75rem 2.2rem;
  border-radius: 6px;
  border: 1px solid #fff;
  background: #fff;
  color: #000;
  font-weight: 700;
  font-size: 0.95rem;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease;
}

.primary-btn:hover { background: #d9d9d9; }

.loading-spinner {
  width: 42px;
  height: 42px;
  border: 3px solid var(--border);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.9s linear infinite;
}

#loading p, #error p {
  color: var(--text-dim);
  font-size: 0.95rem;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

@media (max-width: 720px) {
  html, body {
    height: auto;
    min-height: 100%;
    overflow-y: auto;
    overflow-x: hidden;
  }
  .topbar { padding: 1rem 1rem 0.7rem; }
  .topbar h1 { font-size: 1.6rem; }
  .subtitle { margin: 0.2rem 0 0.7rem; font-size: 0.8rem; }
  .mode-select { margin-bottom: 0.6rem; }
  .board {
    grid-template-columns: 1fr;
    grid-template-rows: auto auto auto;
    height: auto;
    min-height: calc(100vh - 130px);
    padding-bottom: 1.5rem;
  }
  .card { padding: 1.1rem 1rem; gap: 0.5rem; }
  .vs { flex-direction: row; padding: 0.7rem; gap: 1rem; }
  .guess-buttons { flex-direction: row; gap: 0.6rem; }
  .guess-btn { width: 88px; padding: 0.8rem 0.4rem; }
  .card-art { width: 110px; height: 110px; }
  .card-title { font-size: 1.05rem; }
  .card-artist { font-size: 0.85rem; }
  .card-rank { font-size: 1.6rem; margin-top: 0.1rem; min-height: 0; }
  .play-btn { padding: 0.45rem 1rem; font-size: 0.78rem; }
  .panel { padding: 2rem 1.6rem; }
  .topbar-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 0.6rem;
    background: #000;
    padding: 0 0.9rem 0.8rem;
  }
  .best-score, .volume-control {
    position: static;
    padding: 0.4rem 0.6rem;
  }
  .volume-control input[type="range"] { width: 56px; }
}