:root {
  --ink: #29335c;
  --muted: #69739b;
  --surface: #ffffff;
  --surface-soft: #f8f7ff;
  --canvas: #f5f3ff;
  --purple: #6c63ff;
  --purple-soft: #eeeaff;
  --pink: #ff7296;
  --yellow: #ffd166;
  --mint: #62d6b3;
  --mint-soft: #e6fff5;
  --line: #e5e2f5;
  --shadow: 0 12px 28px rgb(41 51 92 / 10%);
}

:root[data-theme="dark"] {
  --ink: #f4f1ff;
  --muted: #c3bddc;
  --surface: #25223c;
  --surface-soft: #302c4c;
  --canvas: #171526;
  --purple: #a9a4ff;
  --purple-soft: #423d6b;
  --pink: #ff9ab5;
  --yellow: #ffe08a;
  --mint: #82e2c5;
  --mint-soft: #1e544c;
  --line: #4a4667;
  --shadow: 0 12px 30px rgb(0 0 0 / 28%);
}

* { box-sizing: border-box; }
body {
  margin: 0;
  min-width: 320px;
  background: radial-gradient(circle at top right, #e8e2ff 0, transparent 28%), var(--canvas);
  color: var(--ink);
  font-family: ui-rounded, "Trebuchet MS", system-ui, sans-serif;
  transition: background .25s ease, color .25s ease;
}
:root[data-theme="dark"] body { background: radial-gradient(circle at top right, #35305b 0, transparent 30%), var(--canvas); }
button, input { font: inherit; }
button { -webkit-tap-highlight-color: transparent; }
.login-screen[hidden], .app-shell[hidden] { display: none !important; }

/* Login */
.login-screen { min-height: 100vh; display: grid; place-items: center; padding: 24px; }
.login-card { width: min(100%, 450px); padding: 42px 36px; border: 1px solid var(--line); border-radius: 34px; background: var(--surface); text-align: center; box-shadow: var(--shadow); }
.login-mascot { position: relative; width: 124px; height: 108px; margin: 0 auto 18px; }
.bear-face { position: absolute; z-index: 2; top: 20px; left: 19px; width: 86px; height: 80px; border-radius: 48% 48% 44% 44%; background: #a36b42; }
.bear-ear { position: absolute; top: 9px; width: 37px; height: 37px; border-radius: 50%; background: #75452a; }
.bear-ear.left { left: 9px; }
.bear-ear.right { right: 9px; }
.bear-eye { position: absolute; top: 29px; width: 14px; height: 18px; border-radius: 50%; background: #21140f; transform-origin: center; }
.bear-eye.left { left: 20px; }
.bear-eye.right { right: 20px; }
.bear-nose { position: absolute; top: 47px; left: 34px; width: 20px; height: 14px; border-radius: 50%; background: #21140f; }
.bear-mouth { position: absolute; top: 61px; left: 38px; width: 13px; height: 7px; border-bottom: 2px solid #21140f; border-radius: 50%; }
@keyframes bearBlink { 0%, 42%, 48%, 100% { transform: scaleY(1); } 45% { transform: scaleY(.1); } }
.login-card:has(#player-name:focus) .bear-eye { animation: bearBlink 2.7s ease-in-out infinite; }
.login-card h1 { margin: 8px 0 10px; font-size: 2rem; }
.login-copy { color: var(--muted); line-height: 1.55; }
.login-card label { display: block; margin-top: 24px; text-align: left; font-weight: 800; }
.login-card input { width: 100%; margin: 8px 0 12px; padding: 15px; border: 2px solid var(--line); border-radius: 14px; color: var(--ink); background: var(--surface-soft); }
.login-card input:focus { outline: 3px solid color-mix(in srgb, var(--purple) 35%, transparent); border-color: var(--purple); }
.privacy-note { display: block; margin-top: 18px; color: var(--muted); }

/* App shell */
.app-shell { display: grid; grid-template-columns: 320px minmax(0, 1fr); gap: 22px; max-width: 1180px; margin: auto; padding: 28px 22px 34px; }
.topbar, .welcome, .app-shell > footer { grid-column: 1 / -1; }
.topbar, .welcome, .activity-heading, .answer-row { display: flex; align-items: center; }
.topbar { gap: 12px; }
.brand-mark { display: grid; place-items: center; width: 48px; height: 48px; border-radius: 16px; background: var(--purple); color: #fff; font-size: 28px; box-shadow: 0 8px 18px color-mix(in srgb, var(--purple) 25%, transparent); }
.eyebrow, .menu-heading p { margin: 0 0 5px; color: var(--purple); font-size: .72rem; font-weight: 900; letter-spacing: .12em; text-transform: uppercase; }
h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 0; font-size: 1.45rem; }
h2 { margin-bottom: 8px; font-size: clamp(1.4rem, 3vw, 2.15rem); }
.theme-toggle { display: inline-flex; align-items: center; gap: 7px; margin-left: auto; padding: 9px 12px; border: 2px solid var(--line); border-radius: 14px; color: var(--ink); background: var(--surface); font-weight: 800; cursor: pointer; }
.theme-toggle:hover { border-color: var(--purple); background: var(--purple-soft); }
.streak { display: flex; align-items: center; gap: 5px; padding: 10px 15px; border: 1px solid color-mix(in srgb, var(--yellow) 60%, var(--line)); border-radius: 18px; background: color-mix(in srgb, var(--yellow) 20%, var(--surface)); color: #b47800; }
:root[data-theme="dark"] .streak { color: var(--yellow); }
.streak span { font-size: 1.4rem; }
.welcome { justify-content: space-between; margin: 18px 0 4px; padding: 28px 34px; border: 1px solid var(--line); border-radius: 28px; background: var(--surface); box-shadow: var(--shadow); }
.welcome p:not(.eyebrow) { margin-bottom: 0; color: var(--muted); }
.mascot { display: grid; place-items: center; width: 90px; height: 90px; border-radius: 32px; background: var(--mint); color: #fff; font-size: 55px; transform: rotate(8deg); }
.mascot span { position: absolute; margin: 40px 0 0; font-size: 26px; }

/* Child-first menu */
.game-sidebar { grid-column: 1; display: grid; gap: 16px; align-self: start; position: sticky; top: 18px; }
.menu-section { padding: 18px; border: 1px solid var(--line); border-radius: 24px; background: var(--surface); box-shadow: var(--shadow); }
.play-section { background: var(--surface-soft); }
.menu-heading { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.menu-heading h2 { margin: 0; font-size: 1.05rem; }
.menu-step { display: grid; place-items: center; flex: 0 0 30px; width: 30px; height: 30px; border-radius: 50%; background: var(--purple); color: #fff; font-weight: 900; }
.operation-picker { display: grid; grid-template-columns: 1fr 1fr; gap: 9px; }
.operation-card { display: flex; align-items: center; gap: 9px; min-width: 0; padding: 11px 9px; border: 2px solid var(--line); border-radius: 17px; color: var(--ink); background: var(--surface); text-align: left; cursor: pointer; transition: transform .15s ease, border-color .15s ease, background .15s ease; }
.operation-card:hover, .operation-card.active { border-color: var(--purple); background: var(--purple-soft); transform: translateY(-2px); }
.operation-card .icon { display: grid; place-items: center; flex: 0 0 36px; width: 36px; height: 36px; border-radius: 12px; background: var(--purple); color: #fff; font-size: 1.55rem; font-weight: 900; }
.operation-card strong, .operation-card small { display: block; }
.operation-card strong { font-size: .9rem; }
.operation-card small { margin-top: 2px; color: var(--muted); font-size: .67rem; line-height: 1.15; }
.game-menu { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; }
.game-mode { min-height: 46px; padding: 8px; border: 2px solid var(--line); border-radius: 13px; color: var(--ink); background: var(--surface); font-size: .76rem; font-weight: 800; text-align: left; cursor: pointer; }
.game-mode:hover, .game-mode.active { border-color: var(--purple); background: var(--purple-soft); color: var(--purple); }
.game-mode span { font-size: 1.1rem; }
.level-picker { display: flex; align-items: center; justify-content: space-between; gap: 8px; margin-top: 16px; padding-top: 14px; border-top: 1px solid var(--line); }
.level-label { color: var(--muted); font-size: .78rem; font-weight: 800; }
.level-picker [role="group"] { display: flex; gap: 5px; }
.level { width: 34px; height: 34px; padding: 0; border: 2px solid var(--line); border-radius: 11px; color: var(--ink); background: var(--surface); font-weight: 900; cursor: pointer; }
.level:hover, .level.active { border-color: var(--purple); background: var(--purple); color: #fff; }

/* Activity */
.activity-card { grid-column: 2; grid-row: 3; padding: 30px 32px; border: 1px solid var(--line); border-radius: 28px; background: var(--surface); box-shadow: var(--shadow); }
.activity-heading { justify-content: space-between; gap: 20px; }
.activity-heading h2 { max-width: 680px; }
.progress { min-width: 150px; color: var(--muted); font-size: .78rem; text-align: right; }
.progress-track { height: 9px; margin-top: 8px; overflow: hidden; border-radius: 9px; background: var(--surface-soft); }
.progress-track i { display: block; height: 100%; border-radius: 9px; background: var(--pink); transition: width .3s; }
.visual-area { display: flex; align-items: center; justify-content: center; gap: 22px; min-height: 170px; margin: 16px 0; flex-wrap: wrap; }
.group { display: flex; flex-wrap: wrap; justify-content: center; gap: 7px; max-width: 250px; padding: 15px; border-radius: 18px; background: var(--surface-soft); }
.group-label { width: 100%; color: var(--muted); font-size: .8rem; text-align: center; }
.animal, .assigned-animal { display: grid; place-items: center; width: 42px; height: 42px; border-radius: 14px; background: color-mix(in srgb, var(--yellow) 34%, var(--surface)); font-size: 1.8rem; box-shadow: 0 3px 0 color-mix(in srgb, var(--yellow) 45%, var(--line)); }
.group.removed { border: 2px dashed var(--pink); background: color-mix(in srgb, var(--pink) 15%, var(--surface)); }
.intro-label { flex-basis: 100%; color: var(--muted); font-size: .85rem; text-align: center; }
.operator { color: var(--purple); font-size: 2rem; font-weight: 900; }
.answer-row { justify-content: center; gap: 12px; flex-wrap: wrap; }
.answer { min-width: 66px; padding: 13px 20px; border: 2px solid var(--line); border-radius: 16px; color: var(--ink); background: var(--surface); font-size: 1.25rem; font-weight: 900; cursor: pointer; }
.answer:hover { border-color: var(--purple); background: var(--purple-soft); }
.answer.correct { border-color: var(--mint); background: var(--mint-soft); color: var(--ink); }
.answer.wrong { border-color: var(--pink); background: color-mix(in srgb, var(--pink) 15%, var(--surface)); }
.feedback { min-height: 25px; margin: 18px 0 0; text-align: center; font-weight: 800; }
.feedback.good { color: #168264; }
:root[data-theme="dark"] .feedback.good { color: var(--mint); }
.feedback.try { color: #df5273; }
.next-button { display: block; margin: 12px auto 0; padding: 13px 22px; border: 0; border-radius: 14px; background: var(--purple); color: #fff; font-weight: 900; cursor: pointer; box-shadow: 0 6px 0 color-mix(in srgb, var(--purple) 62%, #000); }
.next-button:hover { filter: brightness(1.08); transform: translateY(-1px); }
.next-button:active { transform: translateY(3px); box-shadow: 0 3px 0 color-mix(in srgb, var(--purple) 62%, #000); }

/* Game-specific visuals */
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.number-path { display: flex; justify-content: center; gap: 6px; width: 100%; padding: 15px; overflow-x: auto; }
.path-square { display: grid; place-items: center; flex: 0 0 42px; height: 42px; border: 2px solid var(--line); border-radius: 12px; background: var(--surface); font-weight: 800; }
.path-start { border-color: var(--purple); background: var(--purple-soft); }
.path-target { border-color: var(--mint); background: var(--mint-soft); }
.visual-hint { width: 100%; margin: 0; color: var(--muted); text-align: center; }
.comparison-groups { display: flex; justify-content: center; gap: 20px; width: 100%; flex-wrap: wrap; }
.selectable-group { padding: 0; border: 3px solid transparent; border-radius: 21px; background: transparent; cursor: pointer; }
.selectable-group:hover, .selectable-group:focus-visible { border-color: var(--purple); outline: none; }
.selectable-group .group { min-width: 150px; }
.missing-box, .total-box { display: grid; place-items: center; width: 66px; height: 66px; border-radius: 18px; font-size: 2rem; font-weight: 800; }
.missing-box { border: 3px dashed var(--purple); color: var(--purple); background: var(--purple-soft); }
.total-box { background: var(--mint-soft); color: var(--ink); }
.sharing-counter { width: 100%; margin: 0; color: var(--ink); text-align: center; }
.share-recipient { display: grid; justify-items: center; gap: 8px; }
.share-recipient .group { min-width: 140px; }
.assigned-animal { margin: 3px; border: 0; cursor: pointer; }
.assigned-animal:hover, .assigned-animal:focus-visible { outline: 3px solid var(--pink); outline-offset: 2px; background: color-mix(in srgb, var(--pink) 18%, var(--surface)); }
.give-treasure { padding: 8px 12px; border: 2px solid var(--purple); border-radius: 12px; color: var(--purple); background: var(--surface); font-weight: 800; cursor: pointer; }
.give-treasure:hover, .give-treasure:focus-visible { outline: 3px solid var(--purple); outline-offset: 2px; background: var(--purple-soft); }
.empty-share { display: block; padding: 12px 0; color: var(--muted); font-size: .82rem; }
.detective-claim { display: flex; align-items: center; justify-content: center; gap: 14px; width: 100%; padding: 16px; border: 2px dashed var(--yellow); border-radius: 20px; background: color-mix(in srgb, var(--yellow) 12%, var(--surface)); flex-wrap: wrap; }
.detective-claim .group { padding: 10px; }
.detective-claim p { flex-basis: 100%; margin: 0; text-align: center; }
.completion { margin-top: 24px; padding: 24px; border-radius: 22px; background: var(--mint-soft); text-align: center; }
.completion > span { font-size: 3rem; }
.completion h3 { margin: 8px 0; }
.completion p { color: var(--ink); }

.operation-card:focus-visible, .game-mode:focus-visible, .level:focus-visible, .answer:focus-visible, .next-button:focus-visible, .theme-toggle:focus-visible { outline: 3px solid var(--pink); outline-offset: 3px; }
.answer:disabled { cursor: not-allowed; opacity: .55; }
footer { margin-top: 22px; color: var(--muted); font-size: .76rem; text-align: center; }

@media (max-width: 820px) {
  .app-shell { display: block; padding: 20px 15px 28px; }
  .game-sidebar { position: static; grid-template-columns: 1fr 1fr; margin: 20px 0; }
  .activity-card { margin-top: 20px; }
}
@media (max-width: 620px) {
  .topbar { flex-wrap: wrap; }
  .theme-toggle { order: 3; margin-left: 0; }
  .streak { margin-left: auto; }
  .welcome { align-items: flex-start; padding: 22px; }
  .mascot { width: 66px; height: 66px; border-radius: 24px; font-size: 40px; }
  .game-sidebar { display: grid; grid-template-columns: 1fr; }
  .activity-card { padding: 22px 16px; }
  .activity-heading { align-items: flex-start; flex-direction: column; }
  .progress { width: 100%; text-align: left; }
  .operation-picker { grid-template-columns: 1fr 1fr; }
  .visual-area { gap: 10px; }
  .operator { font-size: 1.5rem; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }
}