/* Design tokens: kek.academy palette (kid-friendly, calm) */
:root {
  --color-primary: #3fa9e0;
  --color-primary-dark: #2b8ac2;
  --color-primary-light: #eaf6fd;
  --color-secondary: #4ecdc4;
  --color-secondary-dark: #2f9a92;
  --color-secondary-light: #e7faf8;
  --color-accent: #ffa552;
  --color-accent-dark: #f2883a;
  --color-accent-light: #fff3e6;
  --color-danger: #ff6b6b;
  --color-danger-light: #ffecec;
  --bg: #f6fafd;
  --surface: #ffffff;
  --text: #33475b;
  --text-h: #1d2b3a;
  --text-muted: #7c93ac;
  --border: #e3ecf3;
  --shadow-sm: 0 1px 3px rgba(51, 71, 91, 0.08);
  --shadow-md: 0 4px 14px rgba(51, 71, 91, 0.1);
  --shadow-lg: 0 10px 30px rgba(51, 71, 91, 0.14);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 999px;
  --transition: 0.18s ease;
  --sans: system-ui, 'Segoe UI', Roboto, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-primary: #5cc0f2;
    --color-primary-dark: #3fa9e0;
    --color-primary-light: rgba(63, 169, 224, 0.16);
    --color-secondary: #5fe0d6;
    --color-secondary-dark: #4ecdc4;
    --color-secondary-light: rgba(78, 205, 196, 0.16);
    --color-accent: #ffb670;
    --color-accent-dark: #ffa552;
    --color-accent-light: rgba(255, 165, 82, 0.16);
    --color-danger: #ff8787;
    --color-danger-light: rgba(255, 107, 107, 0.16);
    --bg: #131a20;
    --surface: #1b242c;
    --text: #b8c6d4;
    --text-h: #f1f5f8;
    --text-muted: #7c93ac;
    --border: #2a3540;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 14px rgba(0, 0, 0, 0.35);
    --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.45);
  }
}
/* Shared component classes: buttons, cards, inputs, layout chrome */
.page {
  max-width: 960px;
  margin: 0 auto;
  padding: 32px 24px 60px;
  text-align: left;
  box-sizing: border-box;
}

.page--narrow {
  max-width: 440px;
}

.page-title {
  display: flex;
  align-items: center;
  gap: 10px;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 20px;
  font-size: 15px;
  font-weight: 600;
  font-family: var(--sans);
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), background var(--transition), color var(--transition), opacity var(--transition);
}

.btn:hover:not(:disabled) {
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn:active:not(:disabled) {
  transform: translateY(0);
}

.btn:disabled {
  opacity: 0.55;
  cursor: not-allowed;
  box-shadow: none;
  transform: none;
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
}

.btn-primary:hover:not(:disabled) {
  background: var(--color-primary-dark);
}

.btn-secondary {
  background: var(--surface);
  color: var(--text);
  border: 1.5px solid var(--border);
  box-shadow: none;
}

.btn-secondary:hover:not(:disabled) {
  background: var(--color-primary-light);
  border-color: var(--color-primary);
  color: var(--color-primary-dark);
}

.btn-accent {
  background: var(--color-accent);
  color: #fff;
}

.btn-accent:hover:not(:disabled) {
  background: var(--color-accent-dark);
}

.btn-danger {
  background: var(--color-danger);
  color: #fff;
}

.btn-danger:hover:not(:disabled) {
  opacity: 0.9;
}

.btn-ghost {
  background: transparent;
  color: var(--color-primary);
  box-shadow: none;
  padding: 8px 12px;
}

.btn-ghost:hover:not(:disabled) {
  background: var(--color-primary-light);
  transform: none;
}

.btn-block {
  width: 100%;
}

.btn-sm {
  padding: 6px 14px;
  font-size: 13px;
}

/* Cards */
.card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  padding: 20px 24px;
  text-align: left;
  transition: transform var(--transition), box-shadow var(--transition);
}

.card:hover {
  box-shadow: var(--shadow-lg);
}

.card-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

/* Clickable "row" links styled as cards (classes/subjects/topics lists) */
.list-link-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 16px 20px;
  background: var(--surface);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  text-decoration: none;
  color: var(--text-h);
  font-weight: 600;
  transition: transform var(--transition), box-shadow var(--transition), background var(--transition), color var(--transition);
}

.list-link-card:hover {
  transform: translateX(4px);
  box-shadow: var(--shadow-md);
  background: var(--color-primary-light);
  color: var(--color-primary-dark);
}

.list-link-card__arrow {
  color: var(--color-primary);
  font-size: 18px;
  flex-shrink: 0;
}

/* Forms */
.field {
  margin-bottom: 16px;
  text-align: left;
}

.field label {
  display: block;
  margin-bottom: 6px;
  font-weight: 600;
  color: var(--text-h);
  font-size: 14px;
}

.input {
  width: 100%;
  padding: 10px 14px;
  font-size: 15px;
  font-family: var(--sans);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
  color: var(--text-h);
  box-sizing: border-box;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

.otp-input {
  font-size: 22px;
  text-align: center;
  letter-spacing: 8px;
  font-weight: 700;
}

.form-error {
  background: var(--color-danger-light);
  color: var(--color-danger);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  font-size: 14px;
  margin-bottom: 16px;
  font-weight: 500;
}

.form-success {
  background: var(--color-secondary-light);
  color: var(--color-secondary-dark);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  font-size: 14px;
  margin-bottom: 16px;
  font-weight: 500;
}

/* Badges */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  font-size: 13px;
  font-weight: 700;
  white-space: nowrap;
}

.badge-success {
  background: var(--color-secondary-light);
  color: var(--color-secondary-dark);
}

.badge-warning {
  background: var(--color-accent-light);
  color: var(--color-accent-dark);
}

.badge-neutral {
  background: var(--border);
  color: var(--text-muted);
}

/* App chrome: header / sidebar / footer */
.app-shell {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  background: var(--bg);
}

.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 28px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 10;
}

.app-header__brand {
  font-weight: 800;
  font-size: 20px;
  color: var(--color-primary-dark);
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
}

.app-body {
  display: flex;
  flex: 1;
  align-items: stretch;
}

.app-main {
  flex: 1;
  min-width: 0;
}

.app-footer {
  padding: 14px 28px;
  text-align: center;
  color: var(--text-muted);
  font-size: 13px;
  background: var(--surface);
  border-top: 1px solid var(--border);
}

.sidebar {
  width: 240px;
  flex-shrink: 0;
  background: var(--surface);
  border-right: 1px solid var(--border);
  padding: 20px 12px;
  box-sizing: border-box;
}

.sidebar__nav-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.sidebar__link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-radius: var(--radius-md);
  color: var(--text);
  text-decoration: none;
  font-weight: 600;
  font-size: 15px;
  transition: background var(--transition), color var(--transition);
}

.sidebar__link:hover {
  background: var(--color-primary-light);
  color: var(--color-primary-dark);
}

.sidebar__link--active {
  background: var(--color-primary);
  color: #fff;
  box-shadow: var(--shadow-sm);
}

.sidebar__link--active:hover {
  background: var(--color-primary-dark);
  color: #fff;
}

/* User switcher (child picker in header) */
.user-switcher {
  position: relative;
}

.user-switcher__trigger {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: var(--color-primary-light);
  color: var(--color-primary-dark);
  border: none;
  border-radius: var(--radius-full);
  font-weight: 700;
  font-size: 14px;
  font-family: var(--sans);
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}

.user-switcher__trigger:hover {
  background: var(--color-primary);
  color: #fff;
}

.user-switcher__dropdown {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  background: var(--surface);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  list-style: none;
  margin: 0;
  padding: 6px;
  min-width: 200px;
  z-index: 20;
}

.user-switcher__dropdown li {
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-weight: 500;
  transition: background var(--transition), color var(--transition);
}

.user-switcher__dropdown li:hover {
  background: var(--color-primary-light);
  color: var(--color-primary-dark);
}

/* Modal */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(29, 43, 58, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: 16px;
}

.modal {
  background: var(--surface);
  padding: 32px;
  border-radius: var(--radius-lg);
  max-width: 420px;
  width: 100%;
  box-shadow: var(--shadow-lg);
  text-align: left;
}

/* Misc */
.loading-state {
  text-align: center;
  margin-top: 40px;
  color: var(--text-muted);
  font-size: 16px;
}

.empty-state {
  color: var(--text-muted);
  font-size: 15px;
  padding: 20px 0;
}

.stack {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

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

.gap-sm {
  gap: 8px;
}

.mt-sm {
  margin-top: 8px;
}

.mt-md {
  margin-top: 16px;
}

.mt-lg {
  margin-top: 24px;
}

/* Children management */
.child-card__name {
  font-weight: 700;
  font-size: 17px;
  color: var(--text-h);
}

.child-card__birthdate {
  font-weight: 400;
  font-size: 14px;
  color: var(--text-muted);
}

.stats-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

.stats-table th {
  text-align: left;
  padding: 8px 10px;
  background: var(--bg);
  color: var(--text-muted);
  font-weight: 600;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.4px;
}

.stats-table th:not(:first-child),
.stats-table td:not(:first-child) {
  text-align: center;
}

.stats-table td {
  padding: 8px 10px;
  border-top: 1px solid var(--border);
}

.stats-table__num {
  font-weight: 600;
  color: var(--text-h);
}

/* Training session */
.progress-bar {
  height: 8px;
  border-radius: var(--radius-full);
  background: var(--border);
  overflow: hidden;
  margin-top: 24px;
}

.progress-bar__fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
  transition: width 0.3s ease;
}

.progress-label {
  margin-top: 8px;
  font-size: 13px;
  color: var(--text-muted);
  font-weight: 600;
}

.question-card {
  font-size: 24px;
  padding: 24px;
  background: var(--color-primary-light);
  border-radius: var(--radius-lg);
  text-align: center;
  font-weight: 700;
  color: var(--text-h);
}

.word-chip {
  padding: 8px 18px;
  border: none;
  border-radius: var(--radius-full);
  background: var(--surface);
  box-shadow: var(--shadow-sm);
  font-size: 15px;
  font-weight: 600;
  font-family: var(--sans);
  cursor: pointer;
  transition: transform var(--transition), box-shadow var(--transition), background var(--transition), opacity var(--transition);
}

.word-chip:hover:not(:disabled) {
  background: var(--color-primary-light);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.word-chip:disabled {
  opacity: 0.5;
  cursor: default;
}

.word-chip--selected {
  background: var(--color-secondary-light);
  color: var(--color-secondary-dark);
}

.sentence-drop-zone {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  min-height: 48px;
  border: 2px dashed var(--border);
  padding: 12px;
  border-radius: var(--radius-md);
  background: var(--bg);
}

.feedback {
  font-size: 17px;
  font-weight: 700;
  padding: 14px 18px;
  border-radius: var(--radius-md);
  margin-top: 16px;
}

.feedback--correct {
  background: var(--color-secondary-light);
  color: var(--color-secondary-dark);
}

.feedback--incorrect {
  background: var(--color-danger-light);
  color: var(--color-danger);
}

.answer-choice-btn {
  padding: 10px 22px;
  margin-right: 8px;
  font-size: 18px;
  font-weight: 700;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--surface);
  color: var(--text-h);
  cursor: pointer;
  transition: background var(--transition), border-color var(--transition), transform var(--transition);
}

.answer-choice-btn:hover:not(:disabled) {
  border-color: var(--color-primary);
  background: var(--color-primary-light);
  transform: translateY(-1px);
}

.answer-choice-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.answer-input {
  padding: 10px 14px;
  font-size: 18px;
  width: 100%;
  max-width: 220px;
  font-family: var(--sans);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  box-sizing: border-box;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.answer-input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

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

.text-muted {
  color: var(--text-muted);
}

.row--center {
  justify-content: center;
}

.row--between {
  justify-content: space-between;
}

.instruction-text {
  font-size: 17px;
  color: var(--text);
}

.word-chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.selected-word-chip {
  background: var(--color-secondary-light);
  color: var(--color-secondary-dark);
  padding: 6px 14px;
  border-radius: var(--radius-full);
  font-weight: 600;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font: 16px/1.5 var(--sans);
  letter-spacing: 0.1px;
  color-scheme: light dark;
  color: var(--text);
  background: var(--bg);
  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

#root {
  min-height: 100svh;
  display: flex;
  flex-direction: column;
}

h1,
h2,
h3 {
  font-family: var(--sans);
  font-weight: 700;
  color: var(--text-h);
  margin: 0 0 12px;
}

h1 {
  font-size: 32px;
  letter-spacing: -0.4px;
}

h2 {
  font-size: 24px;
  letter-spacing: -0.24px;
}

h3 {
  font-size: 18px;
}

p {
  margin: 0 0 8px;
}

a {
  color: var(--color-primary);
}

button {
  font-family: var(--sans);
}

code {
  font-family: ui-monospace, Consolas, monospace;
  font-size: 14px;
  padding: 3px 6px;
  border-radius: 4px;
  background: var(--border);
  color: var(--text-h);
}