*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #0f1117;
  --surface: #1a1d27;
  --surface2: #232738;
  --accent: #6c63ff;
  --accent-hover: #837bff;
  --correct: #2ecc71;
  --wrong: #e74c3c;
  --text: #e8eaf0;
  --text-muted: #7a7f94;
  --radius: 14px;
}

body {
  font-family: 'Segoe UI', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 24px 16px;
}

.app {
  width: 100%;
  max-width: 560px;
}

header {
  margin-bottom: 28px;
}

h1 {
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 14px;
  color: var(--text);
  letter-spacing: -0.3px;
}

.stats {
  display: flex;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 8px;
}

#phase-label {
  font-weight: 600;
  color: var(--accent);
}

.progress-bar {
  height: 6px;
  background: var(--surface2);
  border-radius: 99px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), var(--accent-hover));
  border-radius: 99px;
  width: 0%;
  transition: width 0.4s ease;
}

/* Card */
.card {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 36px 32px;
  text-align: center;
  margin-bottom: 20px;
  border: 1px solid rgba(255,255,255,0.05);
}

.word-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 12px;
}

.word {
  font-size: 2rem;
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.5px;
  word-break: break-word;
}

/* Word row with speak icon */
.word-row {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.trenn-badge {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-weight: 400;
  white-space: nowrap;
  align-self: flex-end;
  padding-bottom: 4px;
}

.btn-speak {
  background: none;
  border: none;
  font-size: 1.3rem;
  cursor: pointer;
  opacity: 0.5;
  transition: opacity 0.15s, transform 0.1s;
  padding: 4px;
  line-height: 1;
  flex-shrink: 0;
}

.btn-speak:hover {
  opacity: 1;
  transform: scale(1.15);
}

/* Study phase extras */
.divider {
  height: 1px;
  background: rgba(255,255,255,0.07);
  margin: 24px 0;
}

.translation {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--accent);
  word-break: break-word;
}

.study-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-bottom: 20px;
}

.btn-nav {
  background: var(--surface);
  border: 2px solid rgba(255,255,255,0.06);
  color: var(--text-muted);
  border-radius: var(--radius);
  padding: 16px 14px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s;
}

.btn-nav:hover {
  background: var(--surface2);
  border-color: var(--accent);
  color: var(--text);
}

.btn-nav.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.btn-nav.primary:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
}

.btn-nav.start-quiz {
  display: block;
  width: 100%;
  margin-top: 10px;
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.btn-nav.start-quiz:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
}

/* Options (quiz) */
.options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.option-btn {
  background: var(--surface);
  border: 2px solid rgba(255,255,255,0.06);
  color: var(--text);
  border-radius: var(--radius);
  padding: 16px 14px;
  font-size: 0.95rem;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, transform 0.1s;
  text-align: center;
  line-height: 1.4;
}

.option-btn:hover:not(:disabled) {
  background: var(--surface2);
  border-color: var(--accent);
  transform: translateY(-1px);
}

.option-btn:active:not(:disabled) {
  transform: translateY(0);
}

.option-btn.correct {
  background: rgba(46, 204, 113, 0.15);
  border-color: var(--correct);
  color: var(--correct);
}

.option-btn.wrong {
  background: rgba(231, 76, 60, 0.15);
  border-color: var(--wrong);
  color: var(--wrong);
}

.option-btn:disabled {
  cursor: default;
}

/* Result screen */
.result-card {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 48px 32px;
  text-align: center;
  border: 1px solid rgba(255,255,255,0.05);
}

.result-icon {
  font-size: 3rem;
  margin-bottom: 12px;
}

.result-title {
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.result-score {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--accent);
  margin-bottom: 8px;
}

.result-comment {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-bottom: 28px;
}

.btn-restart {
  display: block;
  width: 100%;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  padding: 14px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, transform 0.1s;
  margin-bottom: 10px;
}

.btn-restart:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.btn-restart.secondary {
  background: var(--surface2);
  color: var(--text-muted);
}

.btn-restart.secondary:hover {
  background: var(--surface);
  color: var(--text);
}

/* Modal */
.modal {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  z-index: 100;
}

.modal.hidden {
  display: none;
}

.modal-box {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 36px 28px;
  width: 100%;
  max-width: 360px;
  text-align: center;
  border: 1px solid rgba(255,255,255,0.08);
}

.modal-box h2 {
  font-size: 1.2rem;
  margin-bottom: 20px;
}

.modal-box label {
  display: block;
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.modal-box select {
  display: block;
  margin: 8px auto 0;
  background: var(--surface2);
  color: var(--text);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 8px;
  padding: 8px 14px;
  font-size: 1rem;
  cursor: pointer;
  outline: none;
}

.hidden {
  display: none !important;
}

@media (max-width: 480px) {
  body { padding: 16px 12px; }
  h1 { font-size: 1.2rem; }
  .word { font-size: 1.5rem; }
  .translation { font-size: 1.2rem; }
  .card { padding: 28px 20px; }
  .result-card { padding: 36px 20px; }
  .options { grid-template-columns: 1fr; }
  .option-btn { padding: 18px 14px; }
  .btn-nav { padding: 18px 14px; }
}