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

:root {
  --bg: #f5f6f8;
  --white: #ffffff;
  --text: #1a1c22;
  --text-secondary: #6b7084;
  --border: #e2e4ea;
  --border-focus: #4f6ef7;
  --accent: #4f6ef7;
  --accent-light: #eef1fe;
  --accent-hover: #3d5be5;
  --correct: #22a867;
  --correct-bg: #eefbf3;
  --correct-border: #b6eacb;
  --wrong: #e5484d;
  --wrong-bg: #fef1f1;
  --wrong-border: #f5c2c2;
  --radius: 14px;
  --radius-sm: 10px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.03);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.06), 0 1px 3px rgba(0,0,0,0.04);
}

body {
  font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 2.5rem 1rem 3rem;
}

.header { text-align: center; margin-bottom: 2rem; }

h1 {
  font-size: 1.85rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text);
}
h1 span { color: var(--accent); }

.subtitle {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-top: 0.3rem;
  font-weight: 500;
}

.container { width: 100%; max-width: 580px; }

/* ── INPUT SCREEN ── */
#input-screen textarea {
  width: 100%;
  min-height: 240px;
  background: var(--white);
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: inherit;
  font-size: 0.85rem;
  line-height: 1.75;
  padding: 1.1rem 1.2rem;
  resize: vertical;
  transition: border-color 0.2s, box-shadow 0.2s;
  box-shadow: var(--shadow-sm);
}
#input-screen textarea:focus {
  outline: none;
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px rgba(79,110,247,0.12);
}
#input-screen textarea::placeholder { color: #b0b5c5; }

.section-label {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
  margin-top: 1.25rem;
}

.options-row {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.direction-btn {
  flex: 1;
  min-width: 120px;
  padding: 0.65rem 0.8rem;
  background: var(--white);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-size: 0.82rem;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.18s;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
}
.direction-btn:hover { border-color: #c5c9d6; background: #fbfbfd; }
.direction-btn.active {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--accent-light);
}

.start-btn {
  width: 100%;
  margin-top: 1.25rem;
  padding: 0.85rem;
  background: var(--accent);
  border: none;
  border-radius: var(--radius-sm);
  color: #fff;
  font-size: 0.95rem;
  font-weight: 700;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.2s;
  box-shadow: 0 2px 8px rgba(79,110,247,0.25);
}
.start-btn:hover { background: var(--accent-hover); transform: translateY(-1px); box-shadow: 0 4px 14px rgba(79,110,247,0.3); }
.start-btn:disabled { opacity: 0.45; cursor: not-allowed; transform: none; box-shadow: none; }

.error-msg {
  color: var(--wrong);
  font-size: 0.82rem;
  font-weight: 500;
  margin-top: 0.5rem;
  display: none;
}

/* ── QUIZ SCREEN ── */
#quiz-screen { display: none; }

.progress-bar-wrap {
  width: 100%;
  height: 5px;
  background: var(--border);
  border-radius: 3px;
  overflow: hidden;
  margin-bottom: 1.25rem;
}
.progress-bar {
  height: 100%;
  background: var(--accent);
  border-radius: 3px;
  transition: width 0.4s ease;
  width: 0%;
}

.stats-row {
  display: flex;
  justify-content: space-between;
  margin-bottom: 1rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-secondary);
}
.stats-row .correct-count { color: var(--correct); }
.stats-row .wrong-count { color: var(--wrong); }

.card {
  background: var(--white);
  border: 1.5px solid var(--border);
  border-radius: 18px;
  padding: 2.25rem 1.75rem 1.75rem;
  text-align: center;
  box-shadow: var(--shadow-md);
  transition: border-color 0.3s, box-shadow 0.3s;
}
.card.state-correct {
  border-color: var(--correct-border);
  background: var(--correct-bg);
}
.card.state-wrong {
  border-color: var(--wrong-border);
  background: var(--wrong-bg);
}

.card-label {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  background: var(--accent-light);
  padding: 0.25rem 0.7rem;
  border-radius: 20px;
  margin-bottom: 1rem;
}

.card-word {
  font-size: 1.7rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 0.35rem;
  line-height: 1.3;
}

.card-sub {
  font-size: 0.82rem;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  line-height: 1.5;
}

.answer-input {
  width: 100%;
  padding: 0.8rem 1rem;
  background: var(--bg);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-size: 1rem;
  font-family: inherit;
  font-weight: 500;
  text-align: center;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.answer-input:focus {
  outline: none;
  border-color: var(--border-focus);
  box-shadow: 0 0 0 3px rgba(79,110,247,0.12);
  background: var(--white);
}
.answer-input:disabled { opacity: 0.5; }

.feedback {
  margin-top: 0.9rem;
  min-height: 2.2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.2rem;
}
.feedback-text { font-weight: 700; font-size: 0.92rem; }
.feedback-text.correct { color: var(--correct); }
.feedback-text.wrong { color: var(--wrong); }
.feedback-answer { font-size: 1.15rem; color: var(--text); font-weight: 700; margin-top: 0.15rem; }

.quiz-actions {
  margin-top: 1.1rem;
  display: flex;
  gap: 0.6rem;
}
.quiz-actions button {
  flex: 1;
  padding: 0.7rem;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 0.88rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.18s;
  border: none;
}

.btn-check { background: var(--accent); color: #fff; }
.btn-check:hover { background: var(--accent-hover); }

.btn-next {
  background: var(--accent);
  color: #fff;
  display: none;
}
.btn-next:hover { background: var(--accent-hover); }

.btn-skip {
  background: var(--white);
  color: var(--text-secondary);
  border: 1.5px solid var(--border) !important;
}
.btn-skip:hover { background: var(--bg); color: var(--text); }

.hint-text {
  font-size: 0.72rem;
  color: #b0b5c5;
  margin-top: 0.75rem;
  font-weight: 500;
}

/* ── RESULT SCREEN ── */
#result-screen { display: none; }

.result-card {
  background: var(--white);
  border: 1.5px solid var(--border);
  border-radius: 18px;
  padding: 2.5rem 2rem;
  text-align: center;
  box-shadow: var(--shadow-md);
}
.result-emoji { font-size: 2.8rem; margin-bottom: 0.6rem; }
.result-title { font-size: 1.5rem; font-weight: 800; letter-spacing: -0.02em; margin-bottom: 0.3rem; }
.result-subtitle { color: var(--text-secondary); font-size: 0.88rem; font-weight: 500; margin-bottom: 1.5rem; }

.result-stats {
  display: flex;
  justify-content: center;
  gap: 2.5rem;
  margin-bottom: 1.75rem;
}
.result-stat-num { font-size: 2rem; font-weight: 800; }
.result-stat-num.green { color: var(--correct); }
.result-stat-num.red { color: var(--wrong); }
.result-stat-label { font-size: 0.75rem; color: var(--text-secondary); font-weight: 600; margin-top: 0.1rem; }

.result-actions { display: flex; gap: 0.6rem; }
.result-actions button {
  flex: 1;
  padding: 0.75rem;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 0.88rem;
  font-weight: 700;
  cursor: pointer;
  border: none;
  transition: all 0.18s;
}
.btn-retry { background: var(--accent); color: #fff; }
.btn-retry:hover { background: var(--accent-hover); }
.btn-retry-wrong { background: var(--bg); color: var(--text); border: 1.5px solid var(--border) !important; }
.btn-retry-wrong:hover { background: var(--border); }
.btn-new { background: var(--white); color: var(--text-secondary); border: 1.5px solid var(--border) !important; }
.btn-new:hover { background: var(--bg); color: var(--text); }

.wrong-list { margin-top: 1.25rem; text-align: left; }
.wrong-list-title {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}
.wrong-item {
  display: flex;
  justify-content: space-between;
  padding: 0.55rem 0.85rem;
  font-size: 0.84rem;
  font-weight: 500;
  border-radius: 8px;
  background: var(--wrong-bg);
  border: 1px solid var(--wrong-border);
  margin-bottom: 0.35rem;
}
.wrong-item span:first-child { color: var(--text); }
.wrong-item span:last-child { color: var(--text-secondary); }

/* ── ANIMATIONS ── */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}
.fade-in { animation: fadeIn 0.3s ease forwards; }

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20%, 60% { transform: translateX(-5px); }
  40%, 80% { transform: translateX(5px); }
}
.shake { animation: shake 0.35s ease; }

@media (max-width: 500px) {
  body { padding: 1.5rem 0.75rem 2rem; }
  h1 { font-size: 1.5rem; }
  .card { padding: 1.75rem 1.25rem 1.5rem; }
  .card-word { font-size: 1.35rem; }
  .options-row { flex-direction: column; }
}