:root {
  --bg: #f5f0eb;
  --surface: #fffcf8;
  --mint: #b8e0d2;
  --mint-dark: #7eb8a4;
  --lavender: #d4c8e8;
  --lavender-dark: #9b8ab8;
  --peach: #f5d5c8;
  --peach-dark: #e8a898;
  --sky: #c5dff8;
  --sky-dark: #7aafd4;
  --text: #4a5568;
  --text-light: #718096;
  --success: #68b88a;
  --error: #e8a0a0;
  --shadow: rgba(74, 85, 104, 0.08);
  --radius: 20px;
  --radius-sm: 12px;
  /* Μεγέθη φιλικά προς παιδιά (touch targets ≥ 48px) */
  --item-size: 70px;
  --item-font: 2.85rem;
  --group-min-w: 150px;
  --group-min-h: 135px;
  --font-game: 1.35rem;
  --font-heading: 1.35rem;
  --eq-size: 2.6rem;
}

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

html {
  height: 100%;
}

body {
  font-family: 'Nunito', sans-serif;
  font-size: 17px;
  background:
    radial-gradient(ellipse 70% 55% at 15% 15%, rgba(184, 224, 210, 0.45) 0%, transparent 55%),
    radial-gradient(ellipse 65% 50% at 85% 85%, rgba(212, 200, 232, 0.4) 0%, transparent 55%),
    radial-gradient(ellipse 50% 40% at 92% 12%, rgba(197, 223, 248, 0.35) 0%, transparent 50%),
    radial-gradient(ellipse 45% 35% at 8% 88%, rgba(245, 213, 200, 0.3) 0%, transparent 50%),
    linear-gradient(155deg, #f8f4ef 0%, #ebe6f2 42%, #e6f0eb 100%);
  height: 100%;
  min-height: 100dvh;
  color: var(--text);
  overflow: hidden;
  position: relative;
}

body::before,
body::after {
  content: '';
  position: fixed;
  border-radius: 50%;
  pointer-events: none;
  z-index: 0;
}

body::before {
  width: min(520px, 55vw);
  height: min(520px, 55vw);
  top: -140px;
  left: -100px;
  background: radial-gradient(circle, rgba(184, 224, 210, 0.22) 0%, transparent 68%);
}

body::after {
  width: min(480px, 50vw);
  height: min(480px, 50vw);
  bottom: -120px;
  right: -80px;
  background: radial-gradient(circle, rgba(212, 200, 232, 0.25) 0%, transparent 68%);
}

.app {
  max-width: 980px;
  width: 100%;
  margin: 0 auto;
  height: 100dvh;
  max-height: 100dvh;
  padding: clamp(0.35rem, 1dvh, 0.75rem) clamp(0.75rem, 2vw, 1.25rem);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  position: relative;
  z-index: 1;
}

.screen {
  display: none;
  animation: fadeIn 0.4s ease;
  flex: 1;
  min-height: 0;
  flex-direction: column;
  overflow: hidden;
}

.screen.active {
  display: flex;
}

#screen-home.screen.active {
  overflow: hidden;
  background: rgba(255, 252, 248, 0.82);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-radius: var(--radius);
  border: 1px solid rgba(255, 255, 255, 0.75);
  box-shadow: 0 12px 40px rgba(74, 85, 104, 0.07);
  padding: 0.2rem 0.85rem 0.45rem;
}

#screen-home .hero {
  padding: clamp(0.04rem, 0.2dvh, 0.22rem) 0.35rem clamp(0.02rem, 0.12dvh, 0.15rem);
}

#screen-home .hero-logo {
  width: clamp(132px, 22dvh, 220px);
  max-height: clamp(132px, 22dvh, 220px);
  margin-bottom: clamp(0.02rem, 0.1dvh, 0.1rem);
}

#screen-home .hero h1 {
  font-size: clamp(1.75rem, 5.8dvh, 2.65rem);
  margin-bottom: 0.02rem;
  line-height: 1.05;
}

#screen-home .subtitle {
  font-size: clamp(0.85rem, 1.85dvh, 1.05rem);
  line-height: 1.3;
}

#screen-home .home-toolbar {
  margin-bottom: clamp(0.2rem, 0.55dvh, 0.4rem);
  padding: clamp(0.3rem, 0.75dvh, 0.5rem) 0.55rem;
}

#screen-home .duel-banner {
  margin-bottom: clamp(0.2rem, 0.55dvh, 0.4rem);
  padding: clamp(0.35rem, 0.95dvh, 0.65rem) 0.75rem;
}

#screen-home .duel-banner-text strong {
  font-size: clamp(1rem, 2.2dvh, 1.2rem);
}

#screen-home .duel-banner-text small {
  font-size: clamp(0.78rem, 1.7dvh, 0.98rem);
}

#screen-home .stages-map {
  flex: 1 1 auto;
  min-height: 0;
  gap: clamp(0.18rem, 0.5dvh, 0.42rem);
  margin: clamp(0.15rem, 0.45dvh, 0.45rem) 0;
  overflow: hidden;
}

#screen-home .stage-card {
  flex: 1 1 0;
  min-height: 0;
  padding: clamp(0.28rem, 0.85dvh, 0.55rem) 0.7rem;
  gap: 0.35rem;
}

#screen-home .stage-card .info h3 {
  font-size: clamp(0.95rem, 2.2dvh, 1.15rem);
  margin-bottom: 0;
}

#screen-home .stage-card .info p {
  font-size: clamp(0.75rem, 1.65dvh, 0.92rem);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

#screen-home .stage-card .stars {
  font-size: clamp(0.95rem, 2dvh, 1.1rem);
}

#screen-home .stats-bar {
  padding: clamp(0.25rem, 0.65dvh, 0.45rem) 0.55rem;
  margin-bottom: 0;
  font-size: clamp(0.88rem, 1.9dvh, 1.05rem);
}

.screen-fit.screen.active,
#screen-complete.screen.active,
#screen-duel-setup.screen.active,
#screen-duel-end.screen.active {
  overflow: hidden;
  background: rgba(255, 252, 248, 0.78);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border-radius: var(--radius);
  border: 1px solid rgba(255, 255, 255, 0.7);
  box-shadow: 0 10px 36px rgba(74, 85, 104, 0.06);
  padding: 0.35rem 1rem 0.75rem;
}

.screen-fit .game-header {
  flex-shrink: 0;
  margin-bottom: 0.35rem;
}

.screen-fit .instruction-box {
  flex-shrink: 0;
  margin-bottom: 0.4rem;
  padding: 0.65rem 0.85rem;
  font-size: clamp(1.3rem, 3.8vmin, 1.65rem);
  line-height: 1.4;
  font-weight: 700;
}

.screen-fit .game-area {
  flex: 1 1 auto;
  min-height: 0;
  overflow-y: auto;
  overflow-x: hidden;
  margin-bottom: 0.4rem;
  padding: 0.55rem 0.75rem;
  display: flex;
  flex-direction: column;
  -webkit-overflow-scrolling: touch;
}

.screen-fit .game-footer {
  flex-shrink: 0;
  padding: 0.5rem 0.65rem;
}

.screen-fit .equation-display {
  font-size: clamp(2.2rem, 6vmin, 3.2rem);
  margin-bottom: 0.5rem;
  gap: 0.55rem;
}

.screen-fit .equation-display .answer-slot {
  width: clamp(3rem, 6.5vmin, 3.85rem);
  height: clamp(3rem, 6.5vmin, 3.85rem);
  min-width: 52px;
  min-height: 52px;
  border-width: 3px;
  border-radius: 12px;
}

.screen-fit .answer-row label {
  font-size: clamp(1.15rem, 2.6vmin, 1.4rem);
}

.screen-fit .answer-slot-input,
.screen-fit #answer-input {
  width: clamp(68px, 9.5vmin, 84px);
  height: clamp(58px, 8vmin, 72px);
  font-size: clamp(1.6rem, 4.2vmin, 2rem);
  border-radius: 12px;
}

.screen-fit .feedback {
  margin-top: 0.35rem;
  font-size: 1.02rem;
  min-height: 1.3rem;
}

.screen-fit .btn-secondary {
  margin-top: 0.35rem;
  padding: 0.6rem;
  font-size: 1.05rem;
}

.screen-fit .btn-primary {
  padding: 0.6rem 1.15rem;
  font-size: 1.05rem;
}

.screen-fit .duel-scoreboard {
  flex-shrink: 0;
  margin-bottom: 0.4rem;
}

.screen-fit .duel-player-card {
  padding: 0.5rem;
}

.screen-fit .duel-score {
  font-size: 1.75rem;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Αρχική */
.hero {
  text-align: center;
  padding: 0.5rem 0.5rem 0.35rem;
  flex-shrink: 0;
}

.hero-logo {
  display: block;
  width: 230px;
  height: auto;
  max-height: 230px;
  margin: 0 auto 0.12rem;
  object-fit: contain;
  animation: float 3s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

.hero h1 {
  font-size: 2.35rem;
  font-weight: 800;
  color: var(--lavender-dark);
  margin-bottom: 0.06rem;
  line-height: 1.05;
}

.subtitle {
  color: var(--text-light);
  font-size: 1.02rem;
  line-height: 1.4;
}

.stages-map {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin: 0.65rem 0;
}

.stage-card {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  padding: 0.6rem 0.85rem;
  background: var(--surface);
  border-radius: var(--radius);
  box-shadow: 0 4px 16px var(--shadow);
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform 0.2s, border-color 0.2s, box-shadow 0.2s;
}

.stage-card:hover:not(.locked) {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px var(--shadow);
}

.stage-card.locked {
  opacity: 0.55;
  cursor: not-allowed;
}

.stage-card.completed {
  border-color: var(--mint-dark);
}

.stage-card .info {
  flex: 1;
  min-width: 0;
}

.stage-card .info h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.1rem;
}

.stage-card .info p {
  font-size: 0.9rem;
  color: var(--text-light);
}

.stage-card .stars {
  margin-left: auto;
  font-size: 1.1rem;
}

/* Αρχική — ρυθμίσεις & μονομαχία */
.home-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
  padding: 0.5rem 0.65rem;
  flex-shrink: 0;
  background: var(--surface);
  border-radius: var(--radius-sm);
  box-shadow: 0 2px 12px var(--shadow);
}

.home-toolbar--compact {
  justify-content: flex-end;
  margin-bottom: clamp(0.15rem, 0.4dvh, 0.35rem);
  padding: clamp(0.2rem, 0.5dvh, 0.35rem) 0.55rem;
  background: transparent;
  box-shadow: none;
}

.grade-picker {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex: 1;
}

.picker-label,
.grade-picker label {
  font-weight: 700;
  font-size: 1rem;
  color: var(--text-light);
  flex-shrink: 0;
}

.grade-picker {
  flex-wrap: wrap;
}

.grade-options--home {
  flex: 1;
  min-width: 0;
}

.grade-options--home .grade-option-name {
  font-size: 0.82rem;
}

.grade-options--home .grade-option {
  padding: 0.5rem 0.3rem;
}

.grade-picker select,
.setup-row select,
#duel-grade {
  font-family: inherit;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 0.45rem 0.75rem;
  border: 2px solid var(--lavender);
  border-radius: var(--radius-sm);
  background: white;
  color: var(--text);
  flex: 1;
  max-width: 100%;
}

.btn-sound {
  width: 46px;
  height: 46px;
  border: none;
  background: var(--mint);
  border-radius: 50%;
  font-size: 1.45rem;
  cursor: pointer;
  box-shadow: 0 2px 8px var(--shadow);
  transition: transform 0.15s, opacity 0.15s;
}

.btn-sound:hover { transform: scale(1.05); }
.btn-sound.muted { opacity: 0.5; background: var(--bg); }

.btn-difficulty {
  border: 2px solid var(--lavender);
  background: var(--surface);
  color: var(--text);
  font-family: inherit;
  font-weight: 700;
  font-size: 0.92rem;
  padding: 0.5rem 0.9rem;
  border-radius: 999px;
  cursor: pointer;
  box-shadow: 0 2px 8px var(--shadow);
  transition: transform 0.15s, background 0.15s, border-color 0.15s;
  touch-action: manipulation;
}

.btn-difficulty:hover { transform: translateY(-1px); border-color: var(--mint-dark); }

.btn-difficulty.active {
  background: linear-gradient(180deg, #f0faf6 0%, #fff 100%);
  border-color: var(--mint-dark);
  color: var(--mint-dark);
}

.home-toolbar--compact { justify-content: space-between; gap: 0.5rem; }

.duel-banner {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.65rem;
  width: 100%;
  padding: 0.75rem 1rem;
  margin-bottom: 0.5rem;
  flex-shrink: 0;
  border: none;
  border-radius: var(--radius);
  background: linear-gradient(135deg, var(--lavender) 0%, var(--sky) 100%);
  cursor: pointer;
  text-align: center;
  box-shadow: 0 4px 16px var(--shadow);
  transition: transform 0.2s;
  font-family: inherit;
}

.duel-banner:hover { transform: translateY(-2px); }

.duel-banner-text {
  display: flex;
  flex-direction: column;
  color: var(--text);
}

.duel-banner-text strong { font-size: 1.2rem; }
.duel-banner-text small { color: var(--text-light); font-size: 0.98rem; }

.duel-banner-arrow {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--lavender-dark);
}

.stage-card.grade-locked {
  opacity: 0.45;
  cursor: not-allowed;
}

.stage-card.no-levels {
  opacity: 0.55;
  cursor: not-allowed;
}

.stage-card.no-levels .info p {
  color: var(--peach-dark);
}

/* Επιλογή διαιρέτη (εκπαιδευτικός) */
.times-table-panel {
  flex-shrink: 0;
  margin-bottom: clamp(0.2rem, 0.55dvh, 0.45rem);
  padding: clamp(0.35rem, 0.85dvh, 0.55rem) 0.65rem;
  background: var(--surface);
  border-radius: var(--radius-sm);
  box-shadow: 0 2px 12px var(--shadow);
  border: 1px solid rgba(212, 200, 232, 0.45);
}

.times-table-header {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.35rem 0.65rem;
  margin-bottom: 0.45rem;
}

.times-table-header .picker-label {
  color: var(--lavender-dark);
}

.picker-hint {
  flex: 1 1 100%;
  font-size: 0.82rem;
  color: var(--text-light);
  line-height: 1.3;
}

.times-table-grid {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 0.35rem;
  margin-bottom: 0.4rem;
}

@media (min-width: 520px) {
  .times-table-grid {
    grid-template-columns: repeat(11, minmax(0, 1fr));
  }
}

.times-table-option {
  min-height: 42px;
  padding: 0.35rem 0.2rem;
  border: 2px solid var(--lavender);
  border-radius: 10px;
  background: #fff;
  font-family: inherit;
  font-size: clamp(0.85rem, 1.8dvh, 0.98rem);
  font-weight: 800;
  color: var(--text);
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s, transform 0.15s;
  touch-action: manipulation;
}

.times-table-option:hover {
  border-color: var(--mint-dark);
  transform: translateY(-1px);
}

.times-table-option.selected {
  border-color: var(--mint-dark);
  background: linear-gradient(180deg, #f0faf6 0%, #fff 100%);
  color: var(--mint-dark);
  box-shadow: 0 2px 8px rgba(126, 184, 164, 0.25);
}

.times-table-actions {
  display: flex;
  gap: 0.45rem;
  flex-wrap: wrap;
}

.times-table-action {
  font-family: inherit;
  font-size: 0.82rem;
  font-weight: 700;
  padding: 0.35rem 0.75rem;
  border: 2px solid var(--sky-dark);
  border-radius: 999px;
  background: var(--sky);
  color: var(--text);
  cursor: pointer;
  touch-action: manipulation;
}

.times-table-action:hover {
  background: #d8ebfa;
}

.times-table-summary {
  margin-top: 0.4rem;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-light);
  line-height: 1.35;
}

.times-table-summary.warning {
  color: var(--peach-dark);
}

#screen-home .times-table-panel {
  margin-bottom: clamp(0.15rem, 0.4dvh, 0.35rem);
  padding: clamp(0.3rem, 0.7dvh, 0.5rem) 0.55rem;
}

#screen-home .picker-hint {
  font-size: clamp(0.68rem, 1.45dvh, 0.82rem);
}

#screen-home .times-table-option {
  min-height: clamp(36px, 5dvh, 42px);
}

#screen-home .times-table-summary {
  font-size: clamp(0.68rem, 1.45dvh, 0.82rem);
  margin-top: 0.3rem;
}

.stats-bar {
  display: flex;
  justify-content: space-between;
  padding: 0.5rem 0.65rem;
  flex-shrink: 0;
  margin-bottom: 0.25rem;
  background: var(--surface);
  border-radius: var(--radius-sm);
  font-weight: 600;
  color: var(--text-light);
}

.hint-text {
  color: var(--text-light);
  margin-bottom: 0.65rem;
  font-size: 1.35rem;
  font-weight: 600;
}

.hint-text.center { text-align: center; margin-top: 1rem; }

.more-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 2rem;
  height: 2rem;
  padding: 0 0.5rem;
  background: var(--lavender);
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--lavender-dark);
}

.group-box.shake-anim {
  animation: shakeBox 0.3s ease;
}

@keyframes shakeBox {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-6px); }
  75% { transform: translateX(6px); }
}

/* Παιχνίδι */
.game-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
}

.btn-back {
  width: 44px;
  height: 44px;
  flex-shrink: 0;
  border: none;
  background: var(--surface);
  border-radius: 50%;
  font-size: 1.4rem;
  cursor: pointer;
  box-shadow: 0 2px 8px var(--shadow);
  transition: background 0.2s;
}

.btn-back:hover {
  background: var(--lavender);
}

.stage-info {
  flex: 1;
}

.stage-badge {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--lavender-dark);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.stage-info h2 {
  font-size: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
}

.level-counter {
  font-weight: 700;
  color: var(--mint-dark);
  background: var(--mint);
  padding: 0.35rem 0.65rem;
  border-radius: 999px;
  font-size: 0.95rem;
  flex-shrink: 0;
}

.instruction-box {
  background: var(--surface);
  padding: 0.75rem 0.95rem;
  border-radius: var(--radius-sm);
  margin-bottom: 0.5rem;
  font-size: var(--font-game);
  font-weight: 700;
  line-height: 1.45;
  border-left: 4px solid var(--mint-dark);
  box-shadow: 0 2px 12px var(--shadow);
}

.game-area {
  background: var(--surface);
  border-radius: var(--radius-sm);
  padding: 0.5rem;
  margin-bottom: 0.5rem;
  box-shadow: 0 4px 20px var(--shadow);
}

/* Αντικείμενα & ομάδες */
.objects-pool {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  justify-content: center;
  align-content: flex-start;
  padding: 0.65rem;
  background: linear-gradient(180deg, #faf8f5 0%, var(--bg) 100%);
  border-radius: var(--radius-sm);
  min-height: 0;
  margin-bottom: 0.5rem;
  border: 2px dashed var(--mint);
  max-height: 38vh;
  overflow-y: auto;
  flex-shrink: 0;
}

.groups-container {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  justify-content: center;
  align-content: center;
  flex: 1 1 auto;
}

.group-box {
  background: linear-gradient(180deg, #fff 0%, #f8f6f3 100%);
  border: 2px solid var(--lavender);
  border-radius: var(--radius-sm);
  padding: 0.6rem 0.65rem;
  min-width: var(--group-min-w);
  min-height: var(--group-min-h);
  transition: border-color 0.2s, transform 0.2s;
}

.group-box.highlight {
  border-color: var(--mint-dark);
  transform: scale(1.02);
}

.group-box.full {
  border-color: var(--mint-dark);
  background: linear-gradient(180deg, #f0faf6 0%, #fff 100%);
}

.group-label {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--lavender-dark);
  text-align: center;
  margin-bottom: 0.45rem;
}

.group-items {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  justify-content: center;
  align-content: center;
  min-height: 56px;
}

.draggable-item {
  width: var(--item-size);
  height: var(--item-size);
  font-size: var(--item-font);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: grab;
  border-radius: 50%;
  background: white;
  box-shadow: 0 2px 8px var(--shadow);
  transition: transform 0.15s;
  user-select: none;
  touch-action: none;
}

.draggable-item:hover {
  transform: scale(1.1);
}

.draggable-item.dragging {
  opacity: 0.6;
  cursor: grabbing;
}

.draggable-item.placed {
  cursor: default;
}

/* Μεγαλύτερα στοιχεία στις οθόνες παιχνιδιού */
.screen-fit .game-area .draggable-item {
  width: clamp(64px, 9vmin, 84px);
  height: clamp(64px, 9vmin, 84px);
  font-size: clamp(2.45rem, 6.5vmin, 3.2rem);
}

.screen-fit .game-area .group-box {
  min-width: clamp(135px, 16vmin, 175px);
  min-height: clamp(125px, 15vmin, 160px);
  padding: 0.75rem 0.85rem;
}

.screen-fit .game-area .group-label {
  font-size: clamp(1.15rem, 3vmin, 1.4rem);
}

.screen-fit .game-area .static-group {
  min-width: clamp(150px, 19vmin, 210px);
  padding: clamp(0.85rem, 2vmin, 1.15rem) clamp(0.95rem, 2.4vmin, 1.25rem);
}

.screen-fit .game-area .static-group .items,
.screen-fit .game-area .story-visual {
  font-size: clamp(2.6rem, 7.5vmin, 3.6rem);
}

.screen-fit .game-area .story-emoji {
  font-size: clamp(3.5rem, 8.5vmin, 4.5rem);
}

.screen-fit .hint-text {
  font-size: clamp(1.25rem, 3.5vmin, 1.55rem);
}

/* Στάδιο 2 - μέτρηση */
.count-visual {
  text-align: center;
}

.big-groups {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  justify-content: center;
  margin: 0.65rem 0;
}

.static-group {
  background: var(--mint);
  border-radius: var(--radius-sm);
  padding: 0.85rem 1rem;
  border: 3px solid var(--mint-dark);
  min-width: 145px;
}

.static-group .items {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  justify-content: center;
  font-size: 2.85rem;
  line-height: 1.2;
  max-width: 340px;
}

/* Στάδιο 3 - σχέση με πολλαπλασιασμό (απλοποιημένο) */
.relation-simple {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.85rem;
  text-align: center;
}

.fact-family {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
}

.fact-line {
  font-size: clamp(1.5rem, 4.2vmin, 2.1rem);
  font-weight: 800;
  color: var(--lavender-dark);
  display: inline-flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
}

.fact-arrow {
  color: var(--peach-dark);
  margin: 0 0.15em;
}

.relation-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 0.85rem;
  align-items: center;
  text-align: center;
  font-size: 1.35rem;
}

.relation-box {
  padding: 0.4rem 0.5rem;
  border-radius: var(--radius-sm);
  font-weight: 700;
}

.relation-box.groups-side {
  background: var(--lavender);
}

.relation-box.total-side {
  background: var(--sky);
}

.relation-symbol {
  font-size: 1.25rem;
  color: var(--lavender-dark);
}

.relation-items {
  font-size: 1.25rem;
  margin-top: 0.3rem;
  line-height: 1.4;
}

/* Στάδιο 4 - πολλαπλή επιλογή */
.quiz-scene {
  display: flex;
  align-items: center;
  justify-content: center;
  flex: 1 1 auto;
  min-height: 0;
  padding: 0.75rem 0.5rem;
}

.quiz-equation {
  font-size: clamp(2.4rem, 7vmin, 3.5rem);
  font-weight: 800;
  color: var(--lavender-dark);
  text-align: center;
  line-height: 1.2;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.55rem;
}

.quiz-equation .answer-slot {
  width: clamp(3rem, 7vmin, 4rem);
  height: clamp(3rem, 7vmin, 4rem);
  min-width: 52px;
  min-height: 52px;
}

.answer-row.quiz-mode {
  display: block;
}

.quiz-choices {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.65rem;
  width: 100%;
}

.quiz-choice {
  min-height: 68px;
  padding: 0.65rem 0.5rem;
  font-family: inherit;
  font-size: clamp(1.75rem, 4.5vmin, 2.2rem);
  font-weight: 800;
  color: var(--lavender-dark);
  background: #fff;
  border: 3px solid var(--lavender);
  border-radius: var(--radius-sm);
  cursor: pointer;
  box-shadow: 0 3px 10px var(--shadow);
  transition: transform 0.15s, border-color 0.15s, background 0.15s;
  touch-action: manipulation;
}

.quiz-choice:hover:not(:disabled) {
  transform: translateY(-2px);
  border-color: var(--mint-dark);
}

.quiz-choice:disabled {
  cursor: default;
  opacity: 0.85;
}

.quiz-choice.correct {
  border-color: var(--success);
  background: linear-gradient(180deg, #f0faf6 0%, #fff 100%);
}

.quiz-choice.wrong {
  border-color: var(--error);
  background: #fff5f5;
  opacity: 0.65;
}

/* Στάδιο 5 - πρόβλημα */
.story-scene {
  text-align: center;
  padding: 0.35rem;
}

.story-emoji {
  font-size: 4rem;
  margin-bottom: 0.5rem;
}

.story-text {
  font-size: 1.35rem;
  line-height: 1.5;
  color: var(--text);
  max-width: 100%;
  margin: 0 auto 0.5rem;
}

.story-visual {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  justify-content: center;
  font-size: 2.75rem;
  line-height: 1.2;
  padding: 0.75rem;
  background: var(--bg);
  border-radius: var(--radius-sm);
  max-height: 28vh;
  overflow-y: auto;
}

/* Στάδιο 6 - υπόλοιπο (μικρότερα στοιχεία ώστε να φαίνεται το κουτί υπολοίπου) */
.remainder-area {
  display: flex;
  flex-direction: column;
  flex: 1 1 auto;
  min-height: 0;
  overflow: hidden;
}

.remainder-area .objects-pool {
  max-height: 20vh;
  padding: 0.4rem;
  gap: 0.3rem;
  margin-bottom: 0.35rem;
  flex-shrink: 1;
}

.remainder-area .groups-container {
  margin-bottom: 0.45rem;
  gap: 0.4rem;
  flex: 0 1 auto;
  max-height: 28vh;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

.remainder-area .group-box {
  min-width: 86px;
  min-height: 76px;
  padding: 0.38rem 0.42rem;
}

.remainder-area .group-label {
  font-size: 0.82rem;
  margin-bottom: 0.22rem;
}

.remainder-area .group-items {
  min-height: 36px;
  gap: 0.22rem;
}

.remainder-area .draggable-item {
  width: 44px;
  height: 44px;
  font-size: 1.65rem;
}

.remainder-area .leftover-box {
  background: var(--peach);
  border: 2px dashed var(--peach-dark);
  border-radius: var(--radius-sm);
  padding: 0.45rem;
  text-align: center;
  margin-top: auto;
  flex-shrink: 0;
}

.remainder-area .leftover-box .label {
  font-weight: 700;
  color: var(--peach-dark);
  margin-bottom: 0.35rem;
  font-size: 0.9rem;
  line-height: 1.25;
}

.remainder-area .leftover-items {
  display: flex;
  flex-wrap: wrap;
  gap: 0.3rem;
  justify-content: center;
  min-height: 44px;
}

.screen-fit .game-area .remainder-area .objects-pool {
  max-height: clamp(72px, 16vmin, 118px);
}

.screen-fit .game-area .remainder-area .groups-container {
  max-height: clamp(96px, 22vmin, 150px);
}

.screen-fit .game-area .remainder-area .draggable-item {
  width: clamp(38px, 5.2vmin, 50px);
  height: clamp(38px, 5.2vmin, 50px);
  font-size: clamp(1.3rem, 3.2vmin, 1.65rem);
}

.screen-fit .game-area .remainder-area .group-box {
  min-width: clamp(74px, 9.5vmin, 96px);
  min-height: clamp(66px, 8.5vmin, 86px);
  padding: 0.32rem 0.38rem;
}

.screen-fit .game-area .remainder-area .group-label {
  font-size: clamp(0.72rem, 1.8vmin, 0.86rem);
}

.screen-fit .game-area .remainder-area .leftover-box .label {
  font-size: clamp(0.78rem, 2vmin, 0.92rem);
}

.answer-row.remainder-mode {
  flex-wrap: wrap;
  gap: 0.5rem;
}

.answer-row.remainder-mode .answer-part {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
}

.answer-row.remainder-mode .answer-slot-input {
  width: 76px;
}

.leftover-box {
  background: var(--peach);
  border: 2px dashed var(--peach-dark);
  border-radius: var(--radius-sm);
  padding: 0.5rem;
  text-align: center;
  margin-top: 0.45rem;
  flex-shrink: 0;
}

.leftover-box .label {
  font-weight: 700;
  color: var(--peach-dark);
  margin-bottom: 0.5rem;
  font-size: 1rem;
}

.leftover-items {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  justify-content: center;
  min-height: 56px;
}

/* Footer */
.game-footer {
  background: var(--surface);
  padding: 0.6rem 0.75rem;
  border-radius: var(--radius-sm);
  box-shadow: 0 4px 16px var(--shadow);
}

.equation-display {
  text-align: center;
  font-size: var(--eq-size);
  font-weight: 800;
  color: var(--lavender-dark);
  margin-bottom: 0.55rem;
  letter-spacing: 0.03em;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  line-height: 1.2;
}

/* Κουτάκι αντί για ? */
.answer-slot {
  display: inline-block;
  width: 3.35rem;
  height: 3.35rem;
  min-width: 52px;
  min-height: 52px;
  border: 3px solid var(--lavender-dark);
  border-radius: 12px;
  background: #fff;
  box-shadow: inset 0 2px 4px rgba(74, 85, 104, 0.06);
  vertical-align: middle;
}

.answer-slot--sm {
  width: 2.65rem;
  height: 2.65rem;
  min-width: 42px;
  min-height: 42px;
  border-width: 2px;
  border-radius: 8px;
}

.answer-slot--inline {
  width: 1.85rem;
  height: 1.85rem;
  min-width: 30px;
  min-height: 30px;
  border-width: 2px;
  border-radius: 6px;
  margin: 0 0.12em;
  vertical-align: -0.15em;
}

.boxes-row {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  justify-content: center;
}

.static-group .items .boxes-row {
  width: 100%;
  padding: 0.25rem 0;
}

.eq-word {
  font-size: 0.88em;
  font-weight: 700;
  color: var(--text-light);
  margin: 0 0.15em;
}

/* Σύμβολο αγνώστου «?» */
.q-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.7em;
  height: 1.7em;
  min-width: 1.7em;
  border-radius: 50%;
  background: var(--peach);
  color: var(--peach-dark);
  font-weight: 800;
  vertical-align: -0.4em;
  line-height: 1;
}

.instruction-box .q-mark { vertical-align: -0.35em; }

.q-mark.q-filled {
  background: var(--mint);
  color: var(--mint-dark);
}

.instruction-box .answer-slot--inline {
  width: 2.1rem;
  height: 2.1rem;
  min-width: 34px;
  min-height: 34px;
  transform: translateY(1px);
}

.relation-grid .answer-slot--inline,
.relation-items .answer-slot--inline {
  width: 2rem;
  height: 2rem;
  min-width: 32px;
  min-height: 32px;
}

.relation-items .boxes-inline {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  flex-wrap: wrap;
  justify-content: center;
}


.answer-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.answer-row label {
  font-weight: 700;
  font-size: 1.35rem;
}

.answer-slot-input,
#answer-input {
  width: 76px;
  height: 64px;
  font-size: 1.85rem;
  font-family: inherit;
  font-weight: 700;
  text-align: center;
  border: 3px solid var(--lavender-dark);
  border-radius: 12px;
  background: #fff;
  color: var(--text);
  box-shadow: inset 0 2px 4px rgba(74, 85, 104, 0.06);
}

.answer-slot-input:focus,
#answer-input:focus {
  outline: none;
  border-color: var(--mint-dark);
}

.num-input-wrap {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  flex-wrap: wrap;
  justify-content: center;
}

.num-input-wrap.is-active .answer-slot-input {
  border-color: var(--mint-dark);
  box-shadow: 0 0 0 3px rgba(126, 184, 164, 0.25);
}

.num-keyboard {
  display: inline-flex;
  align-items: center;
  gap: 0.2rem;
  max-width: 100%;
  overflow-x: auto;
  padding: 0.15rem 0;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.num-keyboard::-webkit-scrollbar {
  display: none;
}

.num-key {
  flex: 0 0 auto;
  min-width: 2.15rem;
  height: 2.15rem;
  padding: 0;
  border: 2px solid var(--lavender-dark);
  border-radius: 10px;
  background: linear-gradient(180deg, #fff 0%, var(--lavender) 100%);
  color: var(--text);
  font-family: inherit;
  font-size: 1.05rem;
  font-weight: 800;
  line-height: 1;
  cursor: pointer;
  transition: transform 0.12s, background 0.12s, border-color 0.12s;
  touch-action: manipulation;
}

.num-key:hover {
  background: #fff;
  border-color: var(--mint-dark);
}

.num-key:active {
  transform: scale(0.94);
  background: var(--mint);
  color: #fff;
  border-color: var(--mint-dark);
}

.num-key--del {
  min-width: 2.5rem;
  font-size: 1.15rem;
  background: linear-gradient(180deg, #fff5f5 0%, #fed7d7 100%);
  border-color: #fc8181;
  color: #c53030;
}

.answer-row.remainder-mode .num-input-wrap {
  flex-direction: row;
  flex-wrap: nowrap;
  align-items: center;
}

.answer-row:not(.remainder-mode) .num-input-wrap {
  flex-wrap: nowrap;
}

@media (max-width: 640px) {
  .num-key {
    min-width: 1.95rem;
    height: 1.95rem;
    font-size: 0.95rem;
    border-radius: 8px;
  }

  .num-key--del {
    min-width: 2.25rem;
  }
}

.screen-fit .num-key {
  min-width: clamp(1.85rem, 4.2vmin, 2.35rem);
  height: clamp(1.85rem, 4.2vmin, 2.35rem);
  font-size: clamp(0.9rem, 2.4vmin, 1.1rem);
}

.screen-fit .num-key--del {
  min-width: clamp(2.1rem, 4.8vmin, 2.75rem);
}

.btn-primary, .btn-secondary {
  font-family: inherit;
  font-weight: 700;
  font-size: 1.1rem;
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 999px;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s;
}

.btn-primary {
  background: linear-gradient(135deg, var(--mint-dark), var(--mint));
  color: white;
  box-shadow: 0 4px 12px rgba(126, 184, 164, 0.4);
}

.btn-primary:hover {
  transform: translateY(-1px);
}

.btn-secondary {
  background: var(--lavender);
  color: var(--lavender-dark);
  margin-top: 0.75rem;
  width: 100%;
}

.feedback {
  text-align: center;
  margin-top: 0.35rem;
  font-weight: 700;
  font-size: 1.02rem;
  min-height: 1.25rem;
}

.feedback.success { color: var(--success); }
.feedback.error { color: var(--error); }

/* Υπόδειξη μετά από λάθη */
.hint-zone {
  text-align: center;
  margin-top: 0.35rem;
}

.btn-hint {
  font-family: inherit;
  font-weight: 700;
  font-size: 0.98rem;
  padding: 0.5rem 1.1rem;
  border: 2px dashed var(--peach-dark);
  border-radius: 999px;
  background: var(--peach);
  color: var(--peach-dark);
  cursor: pointer;
  touch-action: manipulation;
  animation: bounce 0.6s ease;
}

.btn-hint:hover { background: #f8e2d8; }

.hint-message {
  background: #fffaf6;
  border: 2px solid var(--peach);
  border-radius: var(--radius-sm);
  padding: 0.6rem 0.85rem;
  font-size: 1.05rem;
  font-weight: 600;
  line-height: 1.45;
  color: var(--text);
}

.hidden {
  display: none !important;
}

/* Ολοκλήρωση */
#screen-complete.screen.active,
#screen-duel-end.screen.active,
#screen-duel-setup.screen.active {
  justify-content: flex-start;
  overflow-y: auto;
  overflow-x: hidden;
  -webkit-overflow-scrolling: touch;
}

.celebration {
  text-align: center;
  padding: 1rem 0.75rem;
}

.confetti {
  font-size: 2.5rem;
  animation: bounce 0.6s ease infinite alternate;
}

@keyframes bounce {
  from { transform: scale(1); }
  to { transform: scale(1.15); }
}

.celebration h2 {
  font-size: 1.35rem;
  color: var(--mint-dark);
  margin: 0.5rem 0 0.35rem;
}

.celebration p {
  color: var(--text-light);
  font-size: 0.95rem;
  margin-bottom: 0.75rem;
}

.stars-earned {
  font-size: 1.5rem;
  margin-bottom: 0.75rem;
}

/* Δίπλωμα ολοκλήρωσης */
.celebration.certificate {
  border: 4px double var(--lavender-dark);
  border-radius: var(--radius);
  background: linear-gradient(180deg, #fffefb 0%, #faf6ff 100%);
  margin: 0.5rem auto;
  max-width: 560px;
  padding: 1.5rem 1.25rem;
  box-shadow: 0 8px 28px var(--shadow);
}

.celebration.certificate h2 {
  font-size: 1.6rem;
}

.certificate-name {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--lavender-dark);
  margin: 0.35rem 0 0.85rem;
  letter-spacing: 0.02em;
}

@media print {
  body { overflow: visible; background: #fff; }
  body::before, body::after { display: none; }
  .app { height: auto; max-height: none; overflow: visible; }
  .no-print { display: none !important; }
  #screen-complete.screen { display: flex !important; }
  .celebration.certificate { box-shadow: none; }
  .celebration .btn-primary, .celebration .btn-secondary { display: none !important; }
}

/* Μονομαχία */
.duel-setup-card {
  background: var(--surface);
  padding: 0.85rem;
  border-radius: var(--radius);
  box-shadow: 0 4px 20px var(--shadow);
  flex: 1;
  min-height: 0;
  overflow-y: auto;
}

.duel-grade-picker,
.duel-stage-picker {
  margin-bottom: 0.85rem;
  display: block;
  width: 100%;
}

.duel-grade-picker .setup-label,
.setup-label {
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--text);
  margin-bottom: 0.5rem;
  display: block;
}

.setup-hint {
  color: var(--text-light);
  font-size: 0.88rem;
  line-height: 1.45;
  margin-bottom: 0.55rem;
}

.duel-divisors-note {
  margin-top: 0.45rem;
  margin-bottom: 0;
}

.duel-stage-summary {
  font-size: 0.86rem;
  font-weight: 700;
  color: var(--mint-dark);
  margin-top: 0.45rem;
  line-height: 1.4;
}

.duel-stage-summary.warning {
  color: var(--error);
}

#duel-grade-options,
#duel-stage-options {
  display: grid !important;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.5rem;
  width: 100%;
  min-height: 5.5rem;
  visibility: visible;
  opacity: 1;
}

.grade-options {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0.4rem;
  width: 100%;
}

#screen-duel-setup .grade-option {
  display: flex !important;
  min-height: 3.5rem;
  visibility: visible;
  opacity: 1;
}

@media (max-width: 520px) {
  .grade-options {
    grid-template-columns: repeat(2, 1fr);
  }
}

.grade-option {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.2rem;
  padding: 0.55rem 0.4rem;
  border: 2px solid var(--lavender);
  border-radius: var(--radius-sm);
  background: #fff;
  cursor: pointer;
  font-family: inherit;
  transition: border-color 0.15s, background 0.15s, transform 0.15s;
  touch-action: manipulation;
}

.grade-option:hover {
  border-color: var(--mint-dark);
  transform: translateY(-1px);
}

.grade-option.selected {
  border-color: var(--mint-dark);
  background: linear-gradient(180deg, #f0faf6 0%, #fff 100%);
  box-shadow: 0 2px 10px rgba(126, 184, 164, 0.35);
}

.grade-option-name {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text);
  text-align: center;
  line-height: 1.2;
  width: 100%;
}

.grade-option-desc {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-light);
  text-align: center;
  line-height: 1.25;
  width: 100%;
}

.setup-desc {
  color: var(--text-light);
  margin-bottom: 1.25rem;
  line-height: 1.5;
}

.name-inputs {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.name-inputs label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 700;
}

.name-inputs input {
  flex: 1;
  font-family: inherit;
  font-size: 1rem;
  padding: 0.6rem 0.85rem;
  border: 2px solid var(--lavender);
  border-radius: var(--radius-sm);
}

.setup-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.85rem;
}

.setup-row label {
  font-weight: 700;
  min-width: 4rem;
}

.btn-large {
  width: 100%;
  margin-top: 1rem;
  padding: 0.85rem;
  font-size: 1.1rem;
}

.duel-scoreboard {
  display: flex;
  align-items: stretch;
  gap: 0.5rem;
  margin-bottom: 1.25rem;
}

.duel-player-card {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 1rem;
  background: var(--surface);
  border-radius: var(--radius-sm);
  border: 3px solid transparent;
  box-shadow: 0 2px 12px var(--shadow);
  transition: border-color 0.25s, transform 0.25s;
}

.duel-player-card.active {
  border-color: var(--mint-dark);
  transform: scale(1.03);
  background: linear-gradient(180deg, #f0faf6 0%, var(--surface) 100%);
}

.duel-name {
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--text-light);
  margin-bottom: 0.35rem;
  text-align: center;
}

.duel-score {
  font-size: 2rem;
  font-weight: 800;
  color: var(--lavender-dark);
}

.duel-vs {
  display: flex;
  align-items: center;
  font-weight: 800;
  color: var(--peach-dark);
  font-size: 0.9rem;
}

.duel-area { min-height: 0; }

.duel-story .story-text { font-size: 1.15rem; }

#duel-answer-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}

#duel-answer-row .answer-part {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.celebration .btn-secondary { margin-top: 0.5rem; }

/* Μεγάλες οθόνες — πιο πλατύ layout (μόνο όταν χωράει στο ύψος) */
@media (min-width: 768px) and (min-height: 780px) {
  .app {
    max-width: 1040px;
    padding: 1rem 2rem;
  }

  #screen-home.screen.active,
  .screen-fit.screen.active,
  #screen-complete.screen.active,
  #screen-duel-setup.screen.active,
  #screen-duel-end.screen.active {
    padding-left: 1.5rem;
    padding-right: 1.5rem;
  }

  #screen-home .hero h1 { font-size: 2.65rem; }
  #screen-home .subtitle { font-size: 1.05rem; }

  #screen-home .stage-card {
    padding: 0.75rem 1.1rem;
  }

  #screen-home .stage-card .info h3 { font-size: 1.15rem; }
  #screen-home .stage-card .info p { font-size: 0.92rem; }

  .grade-options--home .grade-option-name {
    font-size: 0.88rem;
  }

  #screen-home .duel-banner {
    padding: 0.75rem 1.1rem;
  }
}

/* Μικρές οθόνες / χαμηλό ύψος */
@media (max-height: 720px) {
  #screen-home .hero-logo {
    width: clamp(118px, 18.5dvh, 185px);
    max-height: clamp(118px, 18.5dvh, 185px);
  }

  #screen-home .hero h1 {
    font-size: clamp(1.55rem, 5dvh, 2.25rem);
  }

  #screen-home .subtitle {
    display: none;
  }

  #screen-home .stage-card .info p {
    display: none;
  }

  #screen-home .duel-banner-text small {
    display: none;
  }
}

@media (max-height: 700px) {
  .screen-fit .instruction-box { font-size: clamp(1.15rem, 3.2vmin, 1.4rem); }
  .screen-fit .hint-text { font-size: clamp(1.1rem, 3vmin, 1.3rem); }
  .screen-fit .equation-display { font-size: 2rem; }
  .screen-fit .equation-display .answer-slot {
    width: 2.65rem;
    height: 2.65rem;
    min-width: 46px;
    min-height: 46px;
  }
  .screen-fit .answer-slot-input,
  .screen-fit #answer-input {
    width: 64px;
    height: 54px;
    font-size: 1.55rem;
  }
  .draggable-item { width: 60px; height: 60px; font-size: 2.35rem; }
  .group-box { min-width: 125px; min-height: 115px; }
  .static-group { min-width: 130px; }
  .static-group .items { font-size: 2.25rem; }
  .story-visual { font-size: 2.1rem; max-height: 22vh; }
  .objects-pool { max-height: 34vh; }
  .remainder-area .objects-pool { max-height: 15vh; }
  .remainder-area .groups-container { max-height: 22vh; }
  .remainder-area .draggable-item { width: 40px; height: 40px; font-size: 1.45rem; }
  .remainder-area .group-box { min-width: 78px; min-height: 68px; }
}

@media (max-width: 500px) {
  .app { padding: 0.35rem 0.5rem; }
  .group-box { min-width: 100px; min-height: 92px; }
  .draggable-item { width: 54px; height: 54px; font-size: 2.1rem; }
}

.site-back-link {
  position: fixed;
  top: 0.75rem;
  left: 0.75rem;
  z-index: 50;
  display: inline-block;
  padding: 0.4rem 0.9rem;
  border-radius: 999px;
  background: var(--surface);
  color: var(--lavender-dark);
  font-weight: 700;
  font-size: 0.85rem;
  text-decoration: none;
  box-shadow: 0 2px 8px var(--shadow);
  transition: transform 0.15s ease;
}

.site-back-link:hover {
  transform: translateY(-2px);
}