:root {
  --bg: #0f1620;
  --panel: #1a2533;
  --panel-light: #233044;
  --accent: #4fd1c5;
  --accent-dark: #2ca39a;
  --text: #eef3f8;
  --text-dim: #9fb0c2;
  --correct: #4ade80;
  --incorrect: #f87171;
}

* { box-sizing: border-box; }

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

#app {
  max-width: 700px;
  margin: 0 auto;
  padding: 20px;
  min-height: 100vh;
}

.screen { display: none; }
.screen.active { display: block; }

h1 {
  text-align: center;
  font-size: 2.2rem;
  margin-bottom: 4px;
  letter-spacing: 1px;
}

.subtitle {
  text-align: center;
  color: var(--text-dim);
  margin-top: 0;
  margin-bottom: 28px;
}

.setup-group {
  margin-bottom: 24px;
}

.setup-group h2 {
  font-size: 1.05rem;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 1.5px;
  margin-bottom: 10px;
  font-weight: 600;
}

.options-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

.option-btn {
  background: var(--panel);
  border: 2px solid transparent;
  border-radius: 10px;
  padding: 14px 16px;
  text-align: left;
  cursor: pointer;
  color: var(--text);
  display: flex;
  flex-direction: column;
  gap: 4px;
  transition: border-color 0.15s, background 0.15s, transform 0.1s;
}

.option-btn:hover {
  background: var(--panel-light);
  transform: translateY(-1px);
}

.option-btn.selected {
  border-color: var(--accent);
  background: var(--panel-light);
}

.opt-title { font-weight: 700; font-size: 1.05rem; }
.opt-desc { font-size: 0.82rem; color: var(--text-dim); }

.primary-btn {
  display: block;
  width: 100%;
  margin-top: 8px;
  padding: 14px;
  font-size: 1.1rem;
  font-weight: 700;
  border: none;
  border-radius: 10px;
  background: var(--accent);
  color: #06231f;
  cursor: pointer;
  transition: background 0.15s, opacity 0.15s;
}

.primary-btn:hover:not(:disabled) { background: var(--accent-dark); }
.primary-btn:disabled { opacity: 0.4; cursor: not-allowed; }

.back-link { text-align: center; margin-top: 16px; font-size: 0.9rem; }
.back-link a { color: var(--text-dim); text-decoration: none; }
.back-link a:hover { color: var(--accent); }

.how-to {
  border: 1px solid var(--panel-light);
  border-radius: 8px;
  margin-top: 20px;
  background: var(--panel);
  max-width: 520px;
  width: 100%;
  text-align: left;
}

.how-to-summary {
  display: block;
  padding: 10px 14px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 1px;
  cursor: pointer;
  list-style: none;
  user-select: none;
}
.how-to-summary::-webkit-details-marker { display: none; }
.how-to-summary::before {
  content: "\25B8";
  display: inline-block;
  margin-right: 8px;
  transition: transform 0.2s;
}
details.how-to[open] > .how-to-summary::before { transform: rotate(90deg); }
.how-to-summary:hover { color: var(--text); }

.how-to-body { padding: 0 16px 12px; }
.how-to-body p {
  font-size: 0.9rem;
  color: var(--text-dim);
  line-height: 1.55;
  margin: 0 0 10px;
}
.how-to-body p:last-child { margin-bottom: 0; }
.how-to-body strong { color: var(--text); }

.text-btn {
  background: none;
  border: none;
  color: var(--text-dim);
  cursor: pointer;
  font-size: 0.95rem;
  text-decoration: underline;
  display: block;
  margin: 0 auto;
}

.text-btn:hover { color: var(--text); }

/* ---------- Game screen ---------- */

.game-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.hud {
  display: flex;
  gap: 18px;
  font-weight: 600;
  color: var(--text-dim);
}

#score-counter, #guess-score-counter { color: var(--accent); }

.prompt-text {
  text-align: center;
  font-size: 1.15rem;
  color: var(--text-dim);
  margin-bottom: 20px;
}

.prompt-text strong { color: var(--text); }

.matchup {
  display: flex;
  align-items: stretch;
  gap: 16px;
}

.country-card {
  flex: 1;
  background: var(--panel);
  border: 2px solid transparent;
  border-radius: 14px;
  padding: 28px 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s, transform 0.12s;
  color: var(--text);
  font-family: inherit;
}

.country-card:hover:not(:disabled) {
  background: var(--panel-light);
  border-color: var(--accent);
  transform: translateY(-3px);
}

.country-card:disabled { cursor: default; }

.country-card.correct {
  border-color: var(--correct);
  background: rgba(74, 222, 128, 0.1);
}

.country-card.incorrect {
  border-color: var(--incorrect);
  background: rgba(248, 113, 113, 0.1);
}

.card-flag {
  width: 72px;
  height: auto;
  border-radius: 4px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.4);
}

.card-name {
  font-size: 1.25rem;
  font-weight: 800;
  text-align: center;
  line-height: 1.2;
}

.card-country {
  font-size: 0.85rem;
  color: var(--text-dim);
  font-weight: 500;
  text-align: center;
}

.card-pop {
  font-size: 1rem;
  font-weight: 600;
  color: var(--accent);
  margin-top: 4px;
}

.card-pop.hidden { display: none; }

.vs-badge {
  align-self: center;
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-dim);
  letter-spacing: 2px;
  flex-shrink: 0;
}

.feedback-banner {
  text-align: center;
  padding: 10px 22px;
  border-radius: 8px;
  font-weight: 700;
  font-size: 1.1rem;
  margin-top: 16px;
}

.feedback-banner.correct { background: var(--correct); color: #06270f; }
.feedback-banner.incorrect { background: var(--incorrect); color: #2a0606; }
.feedback-banner.hidden { display: none; }

/* ---------- Guess mode ---------- */

.guess-country {
  display: flex;
  flex-direction: column;
  align-items: center;
  background: var(--panel);
  border-radius: 14px;
  padding: 28px 20px;
  gap: 10px;
  border: 1px solid var(--panel-light);
}

.guess-flag {
  width: 110px;
  height: auto;
  border-radius: 4px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.4);
}

.guess-country-name {
  font-size: 1.8rem;
  font-weight: 800;
  text-align: center;
  margin: 0;
}

.guess-country-sub {
  font-size: 0.95rem;
  color: var(--text-dim);
  font-weight: 500;
}

.slider-area {
  margin: 0 0 8px;
}

.pop-slider {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 8px;
  border-radius: 4px;
  background: var(--panel-light);
  outline: none;
  cursor: pointer;
}

.pop-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent);
  border: 3px solid var(--bg);
  box-shadow: 0 0 8px rgba(79, 209, 197, 0.4);
  cursor: pointer;
}

.pop-slider::-moz-range-thumb {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent);
  border: 3px solid var(--bg);
  box-shadow: 0 0 8px rgba(79, 209, 197, 0.4);
  cursor: pointer;
}

.slider-label {
  text-align: center;
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--accent);
  margin: 12px 0 4px;
}

.slider-ticks {
  display: flex;
  justify-content: space-between;
  font-size: 0.72rem;
  color: var(--text-dim);
  padding: 0 2px;
  margin-bottom: 8px;
}

.guess-feedback {
  margin-top: 16px;
  background: var(--panel);
  border-radius: 12px;
  padding: 20px;
  border: 1px solid var(--panel-light);
}

.guess-feedback.hidden { display: none; }

.guess-result-row {
  display: flex;
  justify-content: space-around;
  gap: 12px;
}

.guess-result-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.guess-result-label {
  font-size: 0.78rem;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 1px;
  font-weight: 600;
}

.guess-result-value {
  font-size: 1.1rem;
  font-weight: 700;
}

.guess-points {
  text-align: center;
  margin-top: 12px;
  font-size: 1.15rem;
  font-weight: 700;
  padding: 8px;
  border-radius: 8px;
}

.guess-points.great { background: var(--correct); color: #06270f; }
.guess-points.good { background: #facc15; color: #1a1500; }
.guess-points.ok { background: #fb923c; color: #1a0f00; }
.guess-points.bad { background: var(--incorrect); color: #2a0606; }

.final-score {
  text-align: center;
  font-size: 1.4rem;
  color: var(--accent);
  font-weight: 700;
}

/* ---------- Duels ---------- */

.duel-hud {
  display: flex;
  align-items: center;
  gap: 10px;
}

.duel-hud.hidden { display: none; }

.duel-player-chip {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 5px 12px;
  border-radius: 8px;
  background: var(--panel-light);
  opacity: 0.5;
  transition: opacity 0.2s, background 0.2s;
  min-width: 72px;
}

.duel-player-chip.active {
  background: var(--accent);
  opacity: 1;
  color: #000;
}

.duel-player-name {
  font-size: 0.72rem;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  max-width: 90px;
  text-overflow: ellipsis;
}

.duel-player-score { font-size: 1.3rem; font-weight: 700; line-height: 1.2; }
.duel-vs { font-size: 0.85rem; color: var(--text-dim); font-weight: 600; }

.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.75);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 200;
}

.modal-overlay.hidden { display: none; }

.modal-box {
  background: var(--panel);
  border-radius: 16px;
  padding: 2rem;
  max-width: 380px;
  width: 90%;
  text-align: center;
}

.modal-box h2 { margin-top: 0; margin-bottom: 0.5rem; }

.player-name-input {
  background: var(--panel-light);
  border: 2px solid var(--panel-light);
  border-radius: 8px;
  color: var(--text);
  font-size: 1rem;
  padding: 12px 16px;
  text-align: center;
  outline: none;
  width: 100%;
  font-family: inherit;
}

.player-name-input:focus { border-color: var(--accent); }
.player-name-input::placeholder { color: var(--text-dim); }

.setup-diff-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px;
  text-align: left;
}

.turn-overlay {
  position: fixed;
  inset: 0;
  background: var(--bg);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
}

.turn-overlay.hidden { display: none; }

.turn-box { text-align: center; }

.turn-label {
  font-size: 0.85rem;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 2px;
  margin: 0 0 10px;
}

.turn-player {
  font-size: 2.6rem;
  font-weight: 800;
  color: var(--accent);
  margin: 0 0 28px;
}

@media (max-width: 600px) {
  .options-grid { grid-template-columns: 1fr; }
  .matchup { flex-direction: column; }
  .vs-badge { align-self: center; }
  h1 { font-size: 1.6rem; }
  .card-name { font-size: 1.1rem; }
  .country-card { padding: 20px 14px; }
}