/* =====================================================
   ETHERLEARNING – Mental Math Styles
   4-level design: Easy / Medium / Hard / Veteran
   Mirrors Sudoku level-card aesthetic
   ===================================================== */

/* ── Level colours ─────────────────────────────────── */
:root {
  --math-easy:          #16A34A;
  --math-easy-light:    #DCFCE7;
  --math-medium:        #2563EB;
  --math-medium-light:  #DBEAFE;
  --math-hard:          #DC2626;
  --math-hard-light:    #FEE2E2;
  --math-veteran:       #7C3AED;
  --math-veteran-light: #EDE9FE;
}

/* ── Page wrapper ──────────────────────────────────── */
.math-page { padding: 32px 0 64px; }

/* ── Level Select Screen ───────────────────────────── */
.mode-select-screen {
  max-width: 900px;
  margin: 0 auto;
  text-align: center;
}

.mode-select-screen h2 { margin-bottom: 12px; }
.mode-select-screen > p {
  margin-bottom: 40px;
  margin-left: auto;
  margin-right: auto;
}

/* 4-column grid */
.modes-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
  margin-bottom: 40px;
}

/* ── Level Cards ───────────────────────────────────── */
.mode-card {
  background: #fff;
  border: 2px solid var(--paper-mid);
  border-radius: var(--radius-xl);
  padding: 28px 20px 24px;
  cursor: pointer;
  transition: transform 0.22s cubic-bezier(0.34,1.56,0.64,1), box-shadow 0.22s, border-color 0.2s;
  text-align: left;
  position: relative;
  overflow: hidden;
}

[data-theme="dark"] .mode-card { background: var(--paper-warm); }

/* Coloured top bar */
.mode-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  border-radius: 2px 2px 0 0;
}

.level-card-easy::before   { background: var(--math-easy); }
.level-card-medium::before { background: var(--math-medium); }
.level-card-hard::before   { background: var(--math-hard); }
.level-card-veteran::before{ background: var(--math-veteran); }

/* Hover lift */
.mode-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.level-card-easy:hover   { border-color: var(--math-easy); }
.level-card-medium:hover { border-color: var(--math-medium); }
.level-card-hard:hover   { border-color: var(--math-hard); }
.level-card-veteran:hover{ border-color: var(--math-veteran); }

/* Icon */
.mode-icon {
  font-size: 2.2rem;
  margin-bottom: 12px;
  display: block;
}

/* Title */
.mode-card h3 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  margin-bottom: 8px;
}

.level-card-easy   h3 { color: var(--math-easy); }
.level-card-medium h3 { color: var(--math-medium); }
.level-card-hard   h3 { color: var(--math-hard); }
.level-card-veteran h3{ color: var(--math-veteran); }

/* Description */
.mode-card p {
  font-size: 0.84rem;
  line-height: 1.6;
  color: var(--ink-soft);
  max-width: none;
  margin: 0 0 16px;
}

/* Tags row */
.math-level-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.math-level-tag {
  font-size: 0.72rem;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: 999px;
  display: inline-block;
  letter-spacing: 0.3px;
}

.tag-easy    { background: var(--math-easy-light);    color: var(--math-easy); }
.tag-medium  { background: var(--math-medium-light);  color: var(--math-medium); }
.tag-hard    { background: var(--math-hard-light);    color: var(--math-hard); }
.tag-veteran { background: var(--math-veteran-light); color: var(--math-veteran); }

/* ── Active Level Badge (in-game) ──────────────────── */
.active-math-badge {
  display: inline-block;
  font-family: var(--font-body);
  font-size: 0.8rem;
  font-weight: 700;
  padding: 5px 16px;
  border-radius: 999px;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.badge-easy    { background: var(--math-easy-light);    color: var(--math-easy); }
.badge-medium  { background: var(--math-medium-light);  color: var(--math-medium); }
.badge-hard    { background: var(--math-hard-light);    color: var(--math-hard); }
.badge-veteran { background: var(--math-veteran-light); color: var(--math-veteran); }

/* ── Game + Ad two-column layout ───────────────────── */
.game-with-ad {
  display: flex;
  justify-content: center;
  align-items: flex-start;
  gap: 32px;
}

.game-main {
  width: 100%;
  max-width: 600px;
  flex-shrink: 0;
}

.game-ad-col {
  position: sticky;
  top: 80px;
  flex-shrink: 0;
  width: 300px;
}

@media (max-width: 1000px) {
  .game-with-ad { justify-content: center; }
  .game-ad-col  { display: none; }
}

/* ── Game Screen ───────────────────────────────────── */
.game-screen {
  max-width: 960px;
  margin: 0 auto;
}

.game-screen.hidden,
.mode-select-screen.hidden,
.results-screen.hidden { display: none; }

/* ── HUD ───────────────────────────────────────────── */
.math-hud {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  border-radius: var(--radius-lg);
  padding: 16px 20px;
  margin-bottom: 16px;
  flex-wrap: wrap;
  gap: 12px;
}

.hud-item { text-align: center; }

.hud-val {
  font-family: var(--font-display);
  font-size: 1.8rem;
  color: var(--ink);
  display: block;
  line-height: 1;
  transition: color 0.3s;
}

.hud-val.warning { color: var(--danger); animation: pulse 1s infinite; }

.hud-lbl {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--ink-faint);
  margin-top: 4px;
}

/* ── Mistake Dots ──────────────────────────────────── */
.mistake-dots-row {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 16px;
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
}

.mistake-dots-row.hidden { display: none; }

.mistake-dots-label {
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ink-faint);
}

.mistake-dots-wrap { display: flex; gap: 8px; }

.math-mistake-dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 2px solid var(--paper-mid);
  background: transparent;
  transition: background 0.2s, border-color 0.2s;
}

.math-mistake-dot.filled {
  background: var(--danger);
  border-color: var(--danger);
}

/* ── Streak Bar ────────────────────────────────────── */
.streak-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  font-size: 0.88rem;
  color: var(--ink-soft);
  opacity: 0.5;
  transition: opacity 0.3s;
}

.streak-bar.active { opacity: 1; }

.streak-flame { font-size: 1.2rem; }

.streak-count {
  font-family: var(--font-display);
  font-size: 1.2rem;
  color: var(--warning);
}

/* ── Question Area ─────────────────────────────────── */
.question-area {
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  border-radius: var(--radius-xl);
  padding: 36px 28px;
  text-align: center;
  margin-bottom: 20px;
  position: relative;
  overflow: hidden;
  min-height: 140px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
}

.q-difficulty {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
  padding: 3px 12px;
  background: var(--accent-glow);
  border-radius: 999px;
}

.question-display {
  font-family: var(--font-display);
  font-size: clamp(2rem, 6vw, 3.2rem);
  color: var(--ink);
  line-height: 1.1;
  word-break: break-word;
}

/* Answer feedback flash */
.feedback-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  opacity: 0;
  pointer-events: none;
  border-radius: var(--radius-xl);
  transition: opacity 0.12s;
}

.feedback-overlay.correct {
  background: rgba(26,158,107,0.12);
  color: var(--success);
  opacity: 1;
}

.feedback-overlay.wrong {
  background: rgba(209,61,61,0.10);
  color: var(--danger);
  opacity: 1;
}

/* ── Multiple Choice Buttons ───────────────────────── */
.choices-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 20px;
}

.choice-btn {
  padding: 18px 12px;
  border-radius: var(--radius-md);
  background: var(--paper-warm);
  border: 2px solid var(--paper-mid);
  font-family: var(--font-display);
  font-size: 1.5rem;
  color: var(--ink);
  cursor: pointer;
  transition: all 0.15s;
  display: flex;
  align-items: center;
  justify-content: center;
  line-height: 1;
}

.choice-btn:hover:not(:disabled) {
  border-color: var(--accent);
  background: var(--accent-glow);
  color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.choice-btn.correct-ans {
  background: rgba(26,158,107,0.15) !important;
  border-color: var(--success) !important;
  color: var(--success) !important;
}

.choice-btn.wrong-ans {
  background: rgba(209,61,61,0.12) !important;
  border-color: var(--danger) !important;
  color: var(--danger) !important;
}

.choice-btn:disabled { cursor: default; opacity: 0.75; transform: none; }

/* ── Answer Input ──────────────────────────────────── */
.type-input-area {
  display: flex;
  gap: 12px;
  margin-bottom: 20px;
}

.answer-input {
  flex: 1;
  padding: 14px 20px;
  background: var(--paper-warm);
  border: 2px solid var(--paper-mid);
  border-radius: var(--radius-md);
  font-family: var(--font-display);
  font-size: 1.8rem;
  color: var(--ink);
  text-align: center;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
  /* hide number spinners */
  -moz-appearance: textfield;
}

.answer-input::-webkit-outer-spin-button,
.answer-input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }

.answer-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.answer-input.correct { border-color: var(--success); }
.answer-input.wrong   { border-color: var(--danger);  }

/* ── Results Screen ────────────────────────────────── */
.results-screen {
  max-width: 520px;
  margin: 0 auto;
  text-align: center;
}

.results-card {
  background: var(--paper-warm);
  border: 1px solid var(--paper-mid);
  border-radius: var(--radius-xl);
  padding: 48px 36px;
  margin-bottom: 24px;
}

.results-emoji { font-size: 3.5rem; margin-bottom: 16px; display: block; }
.results-card h2 { margin-bottom: 8px; }
.results-card > p { margin-bottom: 28px; font-size: 0.95rem; }

.results-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin-bottom: 24px;
}

.result-stat {
  text-align: center;
  padding: 16px 10px;
  background: var(--paper);
  border-radius: var(--radius-md);
  border: 1px solid var(--paper-mid);
}

.result-stat .val {
  font-family: var(--font-display);
  font-size: 2rem;
  color: var(--accent);
  display: block;
  line-height: 1;
}

.result-stat .lbl {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ink-faint);
  margin-top: 6px;
  display: block;
}

.result-detail {
  font-size: 0.88rem;
  color: var(--ink-soft);
  line-height: 1.8;
  padding: 14px 16px;
  background: var(--paper);
  border-radius: var(--radius-md);
  border: 1px solid var(--paper-mid);
}

.results-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ── Responsive ────────────────────────────────────── */
@media (max-width: 780px) {
  .modes-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 480px) {
  .modes-grid { grid-template-columns: 1fr; }
  .math-hud   { justify-content: space-around; }
  .question-display { font-size: 1.7rem; }
}