:root {
  --bg: #f7f7fb;
  --bg-2: #eef4ff;
  --card: rgba(255, 255, 255, 0.9);
  --text: #1f2430;
  --muted: #5d6473;
  --border: rgba(31, 36, 48, 0.12);
  --primary: #4f46e5;
  --primary-2: #0ea5e9;
  --success: #16a34a;
  --danger: #dc2626;
  --warning: #d97706;
  --shadow: 0 24px 60px rgba(31, 36, 48, 0.08);
  --radius: 18px;
  --radius-sm: 12px;
  --font-body: "Trebuchet MS", "Segoe UI", sans-serif;
  --font-head: Georgia, "Times New Roman", serif;
}

.theme-kids {
  --bg: #fff7e8;
  --bg-2: #fff0f8;
  --card: rgba(255, 255, 255, 0.95);
  --text: #382e22;
  --muted: #7a6550;
  --border: rgba(56, 46, 34, 0.1);
  --primary: #f59e0b;
  --primary-2: #ec4899;
  --success: #10b981;
  --danger: #ef4444;
  --warning: #d97706;
}

* {
  box-sizing: border-box;
}

html {
  color-scheme: light;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-body);
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(79, 70, 229, 0.08), transparent 28%),
    radial-gradient(circle at top right, rgba(14, 165, 233, 0.08), transparent 22%),
    linear-gradient(180deg, var(--bg) 0%, #fff 100%);
}

.theme-kids body {
  background:
    radial-gradient(circle at top left, rgba(245, 158, 11, 0.18), transparent 28%),
    radial-gradient(circle at top right, rgba(236, 72, 153, 0.14), transparent 22%),
    linear-gradient(180deg, var(--bg) 0%, #fff 100%);
}

a {
  color: inherit;
  text-decoration: none;
}

code {
  font-family: "Cascadia Mono", "SFMono-Regular", Consolas, monospace;
}

.page-shell {
  width: min(1200px, calc(100% - 32px));
  margin: 0 auto;
  padding-bottom: 56px;
}

.page-main {
  padding: 28px 0 40px;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(18px);
  background: rgba(255, 255, 255, 0.75);
  border-bottom: 1px solid var(--border);
}

.topbar-inner {
  width: min(1200px, calc(100% - 32px));
  margin: 0 auto;
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
}

.brand-mark {
  width: 40px;
  height: 40px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, var(--primary), var(--primary-2));
  color: #fff;
  box-shadow: 0 14px 30px rgba(79, 70, 229, 0.24);
}

.brand-text {
  font-family: var(--font-head);
  font-size: 1.3rem;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.nav-links a {
  padding: 10px 14px;
  border-radius: 999px;
  color: var(--muted);
}

.nav-links a.active,
.nav-links a:hover {
  background: rgba(79, 70, 229, 0.08);
  color: var(--text);
}

.topbar-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.inline {
  display: inline-flex;
}

.btn {
  border: 0;
  border-radius: 999px;
  padding: 12px 18px;
  font-weight: 700;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: transform 120ms ease, box-shadow 120ms ease, background 120ms ease;
  box-shadow: 0 10px 24px rgba(31, 36, 48, 0.06);
  font-family: inherit;
}

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

.btn-sm {
  padding: 8px 14px;
  font-size: 0.92rem;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--primary-2));
  color: #fff;
}

.btn-secondary {
  background: rgba(79, 70, 229, 0.08);
  color: var(--text);
}

.btn-ghost {
  background: transparent;
  color: var(--text);
  box-shadow: none;
}

.btn-danger {
  background: rgba(220, 38, 38, 0.09);
  color: var(--danger);
}

.icon-btn,
.avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.8);
  display: grid;
  place-items: center;
}

.avatar {
  font-weight: 800;
  background: linear-gradient(135deg, rgba(79, 70, 229, 0.12), rgba(14, 165, 233, 0.12));
}

.flash {
  margin: 0 0 18px;
  padding: 14px 16px;
  border-radius: var(--radius-sm);
  background: rgba(79, 70, 229, 0.08);
  border: 1px solid rgba(79, 70, 229, 0.14);
}

.card,
.auth-card,
.info-card,
.mini-card,
.hero-panel,
.hero-copy {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.card,
.auth-card,
.info-card,
.mini-card {
  padding: 22px;
}

.hero {
  display: grid;
  grid-template-columns: 1.8fr 1fr;
  gap: 22px;
  align-items: stretch;
}

.hero-copy {
  padding: 34px;
  overflow: hidden;
  position: relative;
}

.hero-copy::after {
  content: "";
  position: absolute;
  inset: auto -60px -80px auto;
  width: 220px;
  height: 220px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(79, 70, 229, 0.18), transparent 65%);
  pointer-events: none;
}

.hero-copy h1,
.page-head h1,
.card h1,
.card h2,
.auth-card h1,
.auth-card h2 {
  margin: 0;
  font-family: var(--font-head);
  letter-spacing: -0.02em;
}

.hero-copy h1 {
  font-size: clamp(2.4rem, 6vw, 4.6rem);
  line-height: 0.98;
  max-width: 10ch;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--primary);
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.78rem;
}

.lede,
.muted,
.card p,
.auth-card p {
  color: var(--muted);
  line-height: 1.6;
}

.hero-actions,
.actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
}

.hero-panel {
  padding: 22px;
  display: grid;
  gap: 14px;
  align-content: start;
}

.hero-stat {
  padding: 18px;
  border-radius: 18px;
  background: rgba(79, 70, 229, 0.06);
  border: 1px solid rgba(79, 70, 229, 0.1);
}

.hero-stat strong {
  display: block;
  font-size: 2rem;
  font-family: var(--font-head);
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.grid-3,
.metric-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.metric {
  padding: 18px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.82);
  border: 1px solid var(--border);
}

.metric span {
  display: block;
  color: var(--muted);
  margin-bottom: 8px;
}

.metric strong {
  font-family: var(--font-head);
  font-size: 2rem;
}

.page-head {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 18px;
}

.page-head.compact {
  margin-bottom: 12px;
}

.stack {
  display: grid;
  gap: 18px;
}

.stack-tight {
  display: grid;
  gap: 12px;
}

.field {
  display: grid;
  gap: 8px;
}

.input,
.textarea,
select.input {
  width: 100%;
  border-radius: 14px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.9);
  color: var(--text);
  padding: 13px 14px;
  font: inherit;
  outline: none;
}

.textarea {
  resize: vertical;
  min-height: 120px;
}

.inline-form {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: end;
}

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

.word-pair {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  align-items: center;
}

.row-card {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: center;
  padding: 14px 16px;
  border: 1px solid var(--border);
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.84);
}

.badge {
  display: inline-flex;
  align-items: center;
  padding: 6px 10px;
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 700;
}

.badge-success { background: rgba(22, 163, 74, 0.12); color: var(--success); }
.badge-neutral { background: rgba(31, 36, 48, 0.08); color: var(--muted); }

.auth-shell {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.auth-shell.single {
  grid-template-columns: 1fr;
  max-width: 680px;
  margin: 0 auto;
}

.train-shell {
  max-width: 880px;
  margin: 0 auto;
}

.train-topline {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  color: var(--muted);
  font-size: 0.92rem;
}

.progress {
  margin: 12px 0 24px;
  height: 10px;
  background: rgba(31, 36, 48, 0.08);
  border-radius: 999px;
  overflow: hidden;
}

.progress span {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--primary), var(--primary-2));
}

.train-prompt {
  font-family: var(--font-head);
  font-size: clamp(2rem, 6vw, 3.8rem);
  text-align: center;
  margin: 0 0 24px;
}

.choices {
  display: grid;
  gap: 10px;
}

.choices .btn {
  justify-content: flex-start;
}

.hidden {
  display: none;
}

.answer-panel {
  padding-top: 8px;
  text-align: center;
}

.answer-text {
  font-family: var(--font-head);
  font-size: 2rem;
  margin: 0 0 16px;
}

.image-train {
  position: relative;
  display: inline-block;
  max-width: 100%;
  user-select: none;
}

.image-train img {
  max-width: 100%;
  display: block;
  border-radius: 18px;
  box-shadow: var(--shadow);
}

.image-overlay {
  position: absolute;
  inset: 0;
}

.image-region-shell {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 18px;
}

.image-region-canvas img {
  max-width: 100%;
  border-radius: 18px;
  box-shadow: var(--shadow);
  display: block;
}

.image-region-sidebar {
  padding: 18px;
  border-radius: 18px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.82);
}

.word-pick {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 10px 12px;
  background: #fff;
  cursor: pointer;
  text-align: left;
}

.notice {
  border-left: 4px solid var(--warning);
}

.stats-mini {
  display: grid;
  gap: 4px;
  color: var(--muted);
  text-align: right;
}

@media (max-width: 980px) {
  .hero,
  .image-region-shell,
  .auth-shell,
  .grid-2,
  .grid-3,
  .metric-grid {
    grid-template-columns: 1fr;
  }

  .topbar-inner {
    flex-wrap: wrap;
    padding: 12px 0;
  }

  .nav-links {
    order: 3;
    width: 100%;
  }

  .row-card,
  .page-head {
    flex-direction: column;
    align-items: stretch;
  }

  .word-row {
    grid-template-columns: 1fr;
  }
}