/* ===== RESET & BASE ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: 'Segoe UI', 'Comic Sans MS', Tahoma, sans-serif;
  min-height: 100vh;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding: 16px;
  padding-top: max(16px, env(safe-area-inset-top));
  padding-bottom: max(16px, env(safe-area-inset-bottom));
  transition: background 0.5s ease;
  overflow-y: auto;
}

/* ===== THEMES ===== */
.theme-rainbow {
  background: linear-gradient(135deg, #ff9a9e 0%, #fad0c4 25%, #a1c4fd 50%, #c2e9fb 75%, #d4fc79 100%);
}
.theme-rainbow .card { border: 4px solid #ff6b9d; }
.theme-rainbow .btn-primary { background: linear-gradient(135deg, #ff6b9d, #ffa552); }
.theme-rainbow .op-btn.active, .theme-rainbow .level-btn.active, .theme-rainbow .theme-btn.active {
  background: linear-gradient(135deg, #ff6b9d, #ffa552); color: #fff;
}
.theme-rainbow .numpad-submit { background: linear-gradient(135deg, #ff6b9d, #ffa552); }

.theme-ocean {
  background: linear-gradient(135deg, #1a6b8a 0%, #1cb5e0 50%, #48d1cc 100%);
}
.theme-ocean .card { border: 4px solid #0077b6; background: rgba(255,255,255,0.95); }
.theme-ocean .btn-primary { background: linear-gradient(135deg, #0077b6, #00b4d8); }
.theme-ocean .op-btn.active, .theme-ocean .level-btn.active, .theme-ocean .theme-btn.active {
  background: linear-gradient(135deg, #0077b6, #00b4d8); color: #fff;
}
.theme-ocean .numpad-submit { background: linear-gradient(135deg, #0077b6, #00b4d8); }

.theme-space {
  background: linear-gradient(135deg, #0f0c29, #302b63, #24243e);
}
.theme-space .card { border: 4px solid #7b2ff7; background: rgba(20,12,50,0.95); color: #e0d7ff; }
.theme-space .section-label { color: #c4b5fd; }
.theme-space .btn-primary { background: linear-gradient(135deg, #7b2ff7, #00d4ff); }
.theme-space .op-btn, .theme-space .level-btn, .theme-space .theme-btn {
  background: rgba(123,47,247,0.2); color: #e0d7ff; border-color: #7b2ff7;
}
.theme-space .op-btn.active, .theme-space .level-btn.active, .theme-space .theme-btn.active {
  background: linear-gradient(135deg, #7b2ff7, #00d4ff); color: #fff;
}
.theme-space .equation { color: #e0d7ff; }
.theme-space .score-box, .theme-space .question-box, .theme-space .timer-box { color: #e0d7ff; }
.theme-space .title { color: #e0d7ff; }
.theme-space .numpad-submit { background: linear-gradient(135deg, #7b2ff7, #00d4ff); }
.theme-space .numpad-btn {
  background: rgba(123,47,247,0.2); color: #e0d7ff; border-color: #7b2ff7;
}
.theme-space .numpad-back { color: #ff7eb3; }
.theme-space .numpad-display { background: rgba(123,47,247,0.25); color: #e0d7ff; border-color: #7b2ff7; }
.theme-space .choice-btn {
  background: rgba(123,47,247,0.2); color: #e0d7ff; border-color: #7b2ff7;
}

.theme-jungle {
  background: linear-gradient(135deg, #1b4332, #2d6a4f, #52b788);
}
.theme-jungle .card { border: 4px solid #2d6a4f; background: rgba(255,255,255,0.96); }
.theme-jungle .btn-primary { background: linear-gradient(135deg, #2d6a4f, #74c69d); }
.theme-jungle .op-btn.active, .theme-jungle .level-btn.active, .theme-jungle .theme-btn.active {
  background: linear-gradient(135deg, #2d6a4f, #74c69d); color: #fff;
}
.theme-jungle .numpad-submit { background: linear-gradient(135deg, #2d6a4f, #74c69d); }

.theme-candy {
  background: linear-gradient(135deg, #ff77a9, #ffb347, #b39ddb, #80deea);
}
.theme-candy .card { border: 4px solid #e91e8c; }
.theme-candy .btn-primary { background: linear-gradient(135deg, #e91e8c, #ff77a9); }
.theme-candy .op-btn.active, .theme-candy .level-btn.active, .theme-candy .theme-btn.active {
  background: linear-gradient(135deg, #e91e8c, #ff77a9); color: #fff;
}
.theme-candy .numpad-submit { background: linear-gradient(135deg, #e91e8c, #ff77a9); }

.theme-sunset {
  background: linear-gradient(135deg, #f7971e, #ffd200, #ff4e50);
}
.theme-sunset .card { border: 4px solid #f7971e; }
.theme-sunset .btn-primary { background: linear-gradient(135deg, #f7971e, #ff4e50); }
.theme-sunset .op-btn.active, .theme-sunset .level-btn.active, .theme-sunset .theme-btn.active {
  background: linear-gradient(135deg, #f7971e, #ff4e50); color: #fff;
}
.theme-sunset .numpad-submit { background: linear-gradient(135deg, #f7971e, #ff4e50); }

/* ===== SCREENS ===== */
.screen { display: none; width: 100%; max-width: 540px; margin: auto; }
.screen.active { display: flex; justify-content: center; }

/* Choice button hover — only on real pointer devices to prevent iOS sticky-hover */
@media (hover: hover) {
  .theme-rainbow .choice-btn:hover:not(:disabled):not(.correct):not(.incorrect) {
    background: rgba(255, 107, 157, 0.12); border-color: #ff6b9d;
  }
  .theme-ocean .choice-btn:hover:not(:disabled):not(.correct):not(.incorrect) {
    background: rgba(0, 119, 182, 0.1); border-color: #0077b6;
  }
  .theme-space .choice-btn:hover:not(:disabled):not(.correct):not(.incorrect) {
    background: rgba(123, 47, 247, 0.35); border-color: #00d4ff;
  }
  .theme-jungle .choice-btn:hover:not(:disabled):not(.correct):not(.incorrect) {
    background: rgba(45, 106, 79, 0.1); border-color: #2d6a4f;
  }
  .theme-candy .choice-btn:hover:not(:disabled):not(.correct):not(.incorrect) {
    background: rgba(233, 30, 140, 0.1); border-color: #e91e8c;
  }
  .theme-sunset .choice-btn:hover:not(:disabled):not(.correct):not(.incorrect) {
    background: rgba(247, 151, 30, 0.12); border-color: #f7971e;
  }
}

/* ===== CARD ===== */
.card {
  background: rgba(255,255,255,0.96);
  border-radius: 28px;
  padding: 32px 28px;
  width: 100%;
  box-shadow: 0 12px 40px rgba(0,0,0,0.18);
  backdrop-filter: blur(6px);
}

/* ===== WELCOME ===== */
.title {
  font-size: 2.4rem;
  font-weight: 900;
  text-align: center;
  color: #333;
  margin-bottom: 4px;
  letter-spacing: -1px;
}
.subtitle {
  text-align: center;
  color: #666;
  font-size: 1.05rem;
  margin-bottom: 24px;
}
.section-label {
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: #888;
  margin-bottom: 10px;
  margin-top: 20px;
}

/* Operation buttons */
.operation-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-bottom: 4px;
}
.op-btn {
  padding: 14px 10px;
  border: 2.5px solid #ddd;
  border-radius: 14px;
  background: #f7f7f7;
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
  color: #444;
}
.op-btn:hover { transform: translateY(-2px); box-shadow: 0 4px 12px rgba(0,0,0,0.12); }

/* Locked operation buttons (not available for the selected level) */
.op-btn.op-locked {
  opacity: 0.35;
  cursor: not-allowed;
  pointer-events: none;
  filter: grayscale(0.6);
}

/* Mixed Ops / Order of Ops — subtle dashed border to signal "special" */
.op-btn.op-special {
  border-style: dashed;
}

/* Level buttons */
.level-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 10px;
}
.level-btn {
  padding: 12px 8px;
  border: 2.5px solid #ddd;
  border-radius: 14px;
  background: #f7f7f7;
  font-size: 0.9rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
  color: #444;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}
.level-btn span { font-size: 0.72rem; font-weight: 500; opacity: 0.7; }
.level-btn:hover { transform: translateY(-2px); box-shadow: 0 4px 12px rgba(0,0,0,0.12); }

/* Theme buttons */
.theme-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 8px;
}
.theme-btn {
  padding: 10px 6px;
  border: 2.5px solid #ddd;
  border-radius: 12px;
  background: #f7f7f7;
  font-size: 0.82rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
  color: #444;
}
.theme-btn:hover { transform: translateY(-2px); box-shadow: 0 4px 12px rgba(0,0,0,0.12); }

/* ===== PRIMARY BUTTON ===== */
.btn-primary {
  display: block;
  width: 100%;
  padding: 16px;
  margin-top: 24px;
  border: none;
  border-radius: 16px;
  font-size: 1.15rem;
  font-weight: 800;
  color: #fff;
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: 0 6px 20px rgba(0,0,0,0.2);
  letter-spacing: 0.5px;
}
.btn-primary:hover { transform: translateY(-3px); box-shadow: 0 10px 28px rgba(0,0,0,0.25); }
.btn-primary:active { transform: translateY(0); }

.btn-secondary {
  display: block;
  width: 100%;
  padding: 13px;
  margin-top: 10px;
  border: 2.5px solid #ccc;
  border-radius: 16px;
  font-size: 1rem;
  font-weight: 700;
  color: #555;
  background: transparent;
  cursor: pointer;
  transition: all 0.2s ease;
}
.btn-secondary:hover { background: #f0f0f0; }

/* ===== GAME SCREEN ===== */
.game-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
}
.score-box, .question-box, .timer-box {
  font-size: 0.95rem;
  font-weight: 700;
  color: #555;
  background: rgba(0,0,0,0.06);
  padding: 6px 12px;
  border-radius: 20px;
}
.timer-box { min-width: 70px; text-align: center; }
.timer-box.urgent { color: #e53e3e; animation: pulse 0.6s ease infinite alternate; }

@keyframes pulse {
  from { transform: scale(1); }
  to { transform: scale(1.1); }
}

.progress-bar-wrap {
  background: rgba(0,0,0,0.08);
  border-radius: 20px;
  height: 10px;
  overflow: hidden;
  margin-bottom: 20px;
}
.progress-bar {
  height: 100%;
  border-radius: 20px;
  background: linear-gradient(90deg, #43e97b, #38f9d7);
  width: 100%;
  transition: width 1s linear;
}

.feedback {
  text-align: center;
  font-size: 1.3rem;
  font-weight: 800;
  padding: 10px 16px;
  border-radius: 14px;
  margin-bottom: 16px;
  animation: popIn 0.3s ease;
}
.feedback.correct { background: #d4edda; color: #155724; }
.feedback.incorrect { background: #f8d7da; color: #721c24; }
.feedback.hidden { display: none; }

@keyframes popIn {
  from { transform: scale(0.8); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

.equation-wrap {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 90px;
  margin-bottom: 18px;
}
.equation {
  font-size: clamp(2rem, 8vw, 3rem);
  font-weight: 900;
  color: #222;
  text-align: center;
  letter-spacing: 4px;
  animation: slideIn 0.35s ease;
}
@keyframes slideIn {
  from { transform: translateY(-20px); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}

/* ===== MULTIPLE CHOICE (EASY) ===== */
.choice-wrap {
  margin-bottom: 14px;
}
.choice-wrap.hidden { display: none; }

.choice-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.choice-btn {
  padding: 0;
  min-height: 76px;
  font-size: 1.8rem;
  font-weight: 900;
  border: 2.5px solid #ddd;
  border-radius: 18px;
  background: #f7f7f7;
  color: #333;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease, border-color 0.15s ease;
  letter-spacing: 1px;
}
@media (hover: hover) {
  .choice-btn:hover:not(:disabled):not(.correct):not(.incorrect) {
    transform: translateY(-3px);
    box-shadow: 0 6px 18px rgba(0,0,0,0.14);
  }
}
.choice-btn:active:not(:disabled) { transform: translateY(0); }
.choice-btn:disabled { cursor: default; }

.choice-btn.correct {
  background: #d4edda;
  border-color: #28a745;
  color: #155724;
  animation: popIn 0.25s ease;
}
.choice-btn.incorrect {
  background: #f8d7da;
  border-color: #dc3545;
  color: #721c24;
  animation: popIn 0.25s ease;
}

/* ===== NUMBER PAD (MEDIUM / HARD) ===== */
.numpad-wrap {
  margin-bottom: 14px;
}
.numpad-wrap.hidden { display: none; }

.numpad-display {
  font-size: 2.2rem;
  font-weight: 900;
  text-align: center;
  padding: 12px 16px;
  background: rgba(0,0,0,0.05);
  border: 2px solid #ddd;
  border-radius: 14px;
  margin-bottom: 12px;
  min-height: 62px;
  letter-spacing: 6px;
  color: #222;
  transition: color 0.15s ease;
}
.numpad-display.numpad-display-empty {
  color: #bbb;
  letter-spacing: 2px;
}

.numpad-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 10px;
}

.numpad-btn {
  padding: 0;
  min-height: 60px;
  font-size: 1.45rem;
  font-weight: 800;
  border: 2px solid #ddd;
  border-radius: 14px;
  background: #f7f7f7;
  color: #333;
  cursor: pointer;
  transition: transform 0.12s ease, box-shadow 0.12s ease, background 0.12s ease;
  user-select: none;
  -webkit-user-select: none;
}
.numpad-btn:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 5px 14px rgba(0,0,0,0.13);
  background: #efefef;
}
.numpad-btn:active:not(:disabled) { transform: translateY(0); box-shadow: none; }
.numpad-btn:disabled { opacity: 0.45; cursor: default; }

.numpad-back {
  font-size: 1.35rem;
  color: #c0392b;
  background: #fff0ee;
  border-color: #f5c6cb;
}
.numpad-back:hover:not(:disabled) { background: #ffe0dc; }

.numpad-submit {
  font-size: 1.5rem;
  color: #fff;
  border-color: transparent;
  box-shadow: 0 4px 14px rgba(0,0,0,0.18);
}
.numpad-submit:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 7px 20px rgba(0,0,0,0.22);
}

/* Fallback submit color (overridden per-theme above) */
.numpad-submit { background: linear-gradient(135deg, #43e97b, #38f9d7); color: #fff; }

/* ===== HINT ===== */
.hint-row {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 36px;
}
.btn-hint {
  background: none;
  border: 2px solid #ccc;
  border-radius: 10px;
  padding: 6px 14px;
  font-size: 0.85rem;
  font-weight: 700;
  color: #777;
  cursor: pointer;
  transition: all 0.2s;
}
.btn-hint:hover { background: #f0f0f0; }
.hint-text {
  font-size: 0.9rem;
  color: #666;
  font-weight: 600;
}
.hint-text.hidden { display: none; }

/* ===== RESULTS SCREEN ===== */
.result-emoji {
  font-size: 5rem;
  text-align: center;
  margin-bottom: 8px;
  animation: bounce 0.5s ease infinite alternate;
}
@keyframes bounce {
  from { transform: translateY(0); }
  to { transform: translateY(-8px); }
}

.result-title {
  font-size: 2rem;
  font-weight: 900;
  text-align: center;
  color: #333;
  margin-bottom: 6px;
}
.result-subtitle {
  text-align: center;
  color: #666;
  font-size: 1rem;
  margin-bottom: 24px;
}

.result-stats {
  display: flex;
  gap: 12px;
  margin-bottom: 8px;
}
.stat-box {
  flex: 1;
  background: rgba(0,0,0,0.05);
  border-radius: 16px;
  padding: 18px 8px;
  text-align: center;
}
.stat-num {
  font-size: 2rem;
  font-weight: 900;
  color: #333;
  line-height: 1;
}
.stat-label {
  font-size: 0.75rem;
  color: #888;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-top: 4px;
}

/* ===== CONFETTI ===== */
#confetti-container {
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  pointer-events: none;
  overflow: hidden;
  z-index: 999;
}
.confetti-piece {
  position: absolute;
  width: 10px;
  height: 10px;
  border-radius: 2px;
  opacity: 0;
  animation: confettiFall linear forwards;
}
@keyframes confettiFall {
  0% { transform: translateY(-20px) rotate(0deg); opacity: 1; }
  100% { transform: translateY(110vh) rotate(720deg); opacity: 0; }
}

/* ===== RESPONSIVE ===== */

/* --- Mobile S: very small phones (< 360px) --- */
@media (max-width: 359px) {
  body { padding: 10px; }
  .card { padding: 16px 12px; border-radius: 20px; }
  .title { font-size: 1.65rem; letter-spacing: -0.5px; }
  .operation-grid { grid-template-columns: 1fr 1fr; gap: 8px; }
  .level-grid { grid-template-columns: 1fr 1fr 1fr; gap: 6px; }
  .theme-grid { grid-template-columns: 1fr 1fr; gap: 6px; }
  .op-btn { padding: 12px 6px; font-size: 0.88rem; }
  .level-btn { padding: 10px 4px; font-size: 0.8rem; }
  .level-btn span { font-size: 0.65rem; }
  .theme-btn { padding: 9px 4px; font-size: 0.75rem; }
  .btn-primary { font-size: 1rem; padding: 14px; }
  .game-header { flex-direction: column; align-items: stretch; gap: 6px; }
  .score-box, .question-box, .timer-box { text-align: center; font-size: 0.85rem; }
  .equation-wrap { min-height: 70px; margin-bottom: 14px; }
  .equation { font-size: clamp(1.7rem, 9vw, 2.4rem); letter-spacing: 2px; }
  /* Choice */
  .choice-btn { min-height: 62px; font-size: 1.5rem; border-radius: 14px; }
  .choice-grid { gap: 9px; }
  /* Numpad */
  .numpad-display { font-size: 1.8rem; min-height: 52px; padding: 10px 12px; }
  .numpad-btn { min-height: 50px; font-size: 1.25rem; border-radius: 12px; }
  .numpad-grid { gap: 8px; }
  /* Results */
  .stat-num { font-size: 1.5rem; }
  .result-emoji { font-size: 3.8rem; }
  .result-title { font-size: 1.6rem; }
}

/* --- Mobile M: standard phones (360px – 480px) --- */
@media (min-width: 360px) and (max-width: 480px) {
  .card { padding: 20px 16px; }
  .title { font-size: 2rem; }
  .theme-grid { grid-template-columns: 1fr 1fr 1fr; gap: 8px; }
  .game-header { flex-wrap: wrap; gap: 8px; }
  .question-box { flex: 1 1 100%; text-align: center; order: -1; }
  .equation-wrap { min-height: 76px; margin-bottom: 14px; }
  .equation { font-size: clamp(2rem, 9vw, 2.8rem); }
  /* Choice */
  .choice-btn { min-height: 68px; font-size: 1.65rem; }
  .choice-grid { gap: 10px; }
  /* Numpad */
  .numpad-display { font-size: 2rem; min-height: 56px; }
  .numpad-btn { min-height: 54px; font-size: 1.35rem; }
  .numpad-grid { gap: 9px; }
}

/* --- Mobile L: large phones (481px – 600px) --- */
@media (min-width: 481px) and (max-width: 600px) {
  .screen { max-width: 480px; }
  .game-header { gap: 10px; }
  .choice-btn { min-height: 72px; font-size: 1.75rem; }
  .numpad-btn { min-height: 56px; font-size: 1.4rem; }
}

/* --- Tablet (601px – 900px) --- */
@media (min-width: 601px) and (max-width: 900px) {
  body { padding: 24px 20px; align-items: center; }
  .screen { max-width: 580px; }
  .card { padding: 36px 32px; border-radius: 32px; }
  .title { font-size: 2.6rem; }
  .operation-grid { gap: 12px; }
  .op-btn { padding: 16px 12px; font-size: 1.05rem; }
  .level-btn { padding: 14px 10px; font-size: 0.95rem; }
  .theme-btn { padding: 12px 8px; font-size: 0.88rem; }
  .btn-primary { font-size: 1.2rem; padding: 18px; }
  .equation-wrap { min-height: 100px; }
  .equation { font-size: clamp(2.4rem, 6vw, 3.2rem); }
  /* Choice */
  .choice-btn { min-height: 88px; font-size: 2rem; border-radius: 20px; }
  .choice-grid { gap: 14px; }
  /* Numpad */
  .numpad-display { font-size: 2.4rem; min-height: 68px; padding: 14px 20px; }
  .numpad-btn { min-height: 68px; font-size: 1.6rem; border-radius: 16px; }
  .numpad-grid { gap: 12px; }
  /* Results */
  .result-emoji { font-size: 5.5rem; }
  .result-title { font-size: 2.2rem; }
  .stat-num { font-size: 2.2rem; }
}

/* --- Desktop (901px+) --- */
@media (min-width: 901px) {
  body { padding: 32px; align-items: center; }
  .screen { max-width: 600px; }
  .card { padding: 40px 36px; border-radius: 36px; }
  .title { font-size: 2.8rem; }
  .operation-grid { gap: 14px; }
  .op-btn { padding: 18px 14px; font-size: 1.1rem; border-radius: 16px; }
  .level-btn { padding: 16px 10px; font-size: 1rem; border-radius: 16px; }
  .theme-btn { padding: 12px 8px; font-size: 0.9rem; border-radius: 14px; }
  .btn-primary { font-size: 1.25rem; padding: 20px; border-radius: 18px; }
  .btn-secondary { font-size: 1.05rem; padding: 15px; }
  .equation-wrap { min-height: 110px; }
  .equation { font-size: 3.4rem; }
  /* Choice */
  .choice-btn { min-height: 96px; font-size: 2.2rem; border-radius: 22px; }
  .choice-grid { gap: 16px; }
  /* Numpad */
  .numpad-display { font-size: 2.6rem; min-height: 72px; padding: 14px 24px; }
  .numpad-btn { min-height: 72px; font-size: 1.7rem; border-radius: 16px; }
  .numpad-grid { gap: 12px; }
  /* Results */
  .result-emoji { font-size: 6rem; }
  .result-title { font-size: 2.4rem; }
  .stat-num { font-size: 2.4rem; }
  /* Subtle hover lifts only on non-touch devices */
  .op-btn:hover, .level-btn:hover, .theme-btn:hover { transform: translateY(-3px); }
}

/* --- Touch devices: remove hover transforms (avoids stuck states) --- */
@media (hover: none) {
  .op-btn:hover, .level-btn:hover, .theme-btn:hover,
  .btn-primary:hover, .btn-secondary:hover, .btn-hint:hover,
  .numpad-btn:hover {
    transform: none;
    box-shadow: none;
  }
  /* Bigger tap targets on touch */
  .op-btn { min-height: 52px; }
  .level-btn { min-height: 52px; }
  .theme-btn { min-height: 44px; }
  .btn-primary { min-height: 56px; }
  .btn-hint { min-height: 40px; padding: 10px 18px; }
  .choice-btn { min-height: 72px; }
  .numpad-btn { min-height: 60px; }
}

.homepage-footer {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  text-align: center;
  font-size: 0.75rem;
  opacity: 0.6;
  padding: 0.75rem;
  color: inherit;
}