* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
.icon { display: block; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: var(--accent); }
h1, h2, h3, h4 { line-height: 1.25; margin: 0 0 var(--space-3); }
p { line-height: 1.55; }
button { font-family: inherit; }

/* ---------- shell layout ---------- */
.app-shell { display: flex; flex-direction: column; min-height: 100vh; }

.topbar {
  height: var(--topbar-h);
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: 0 var(--space-4);
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 40;
}
.topbar .brand {
  font-weight: 700;
  font-size: 1rem;
  color: var(--text);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-right: auto;
  min-width: 0;
  flex: 0 1 auto;
  overflow: hidden;
}
.topbar .brand span:last-child { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.topbar .brand .logo-mark {
  width: 28px; height: 28px;
  border-radius: var(--radius-sm);
  overflow: hidden;
  display: flex; align-items: center; justify-content: center;
  flex: 0 0 auto;
}
.topbar .brand .logo-mark img { width: 100%; height: 100%; display: block; }
.topbar-actions { display: flex; align-items: center; gap: var(--space-2); flex: 0 0 auto; }

.icon-btn {
  width: 36px; height: 36px;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  background: transparent;
  color: var(--text);
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  text-decoration: none;
  font-size: 1rem;
}
.icon-btn:hover { background: var(--bg-sunken); }
.icon-btn.active { background: var(--accent); color: var(--accent-contrast); }
.icon-btn:focus-visible, a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible {
  outline: 2px solid var(--focus-ring);
  outline-offset: 2px;
}
#app:focus { outline: none; }

/* ---------- top navigation (5 pantallas: Palabras/Traducir/Practicar/Frases/Examen) ---------- */
.topnav {
  flex: 0 0 auto;
  display: flex;
  justify-content: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-2);
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border);
  overflow-x: auto;
  position: sticky;
  top: var(--topbar-h);
  z-index: 39;
}
/* Icono arriba y nombre debajo; los botones se reparten el ancho de la
   barra para que quepan todos en un celular sin desplazar la barra. El
   max-width evita botones enormes en pantallas anchas. */
.topnav-link {
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 2px;
  padding: var(--space-1) 2px;
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.7rem;
  font-weight: 700;
  white-space: nowrap;
  flex: 1 1 0;
  min-width: 0;
  max-width: 140px;
}
.topnav-link span { max-width: 100%; overflow: hidden; text-overflow: ellipsis; }
.topnav-link:hover { background: var(--bg-sunken); color: var(--text); }
.topnav-link.active { background: var(--accent); color: var(--accent-contrast); }
.topnav[hidden] { display: none; }

.app-body { flex: 1 1 auto; display: flex; min-height: 0; }
.content { flex: 1 1 auto; min-width: 0; padding: var(--space-5); max-width: 1100px; margin: 0 auto; width: 100%; }

/* ---------- transicion entre pantallas ---------- */
@keyframes view-fade-in {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: none; }
}
.content.view-enter { animation: view-fade-in 180ms ease-out; }
@media (prefers-reduced-motion: reduce) {
  .content.view-enter { animation: none; }
}

/* ---------- typography helpers ---------- */
.page-title { font-size: 1.5rem; font-weight: 800; margin-bottom: var(--space-1); }
.page-subtitle { color: var(--text-muted); margin: 0 0 var(--space-5); max-width: 65ch; }
.section-title { font-size: 1.05rem; font-weight: 700; margin: var(--space-6) 0 var(--space-3); }
.text-muted { color: var(--text-muted); }
.text-sm { font-size: 0.85rem; }
.mono { font-family: var(--font-mono); }

/* ---------- cards ---------- */
.card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  box-shadow: var(--shadow-sm);
}
.card + .card { margin-top: var(--space-4); }

.help-list { margin: 0; padding-left: 1.2em; display: flex; flex-direction: column; gap: var(--space-2); }
.help-list li { line-height: 1.5; }
.view-ayuda p, .view-ayuda li, .view-config p { text-align: justify; }
/* La tarjeta de desarrollador no se justifica: en celular abria huecos en el nombre. */
.view-ayuda .dev-card p { text-align: left; }

/* ---------- tarjeta de desarrollador (Ayuda) ---------- */
.dev-card { display: flex; flex-direction: column; gap: var(--space-4); }
.dev-header { display: flex; align-items: center; gap: var(--space-3); }
.dev-avatar {
  width: 48px; height: 48px; border-radius: 50%; flex: 0 0 auto;
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  color: var(--accent-contrast);
  display: flex; align-items: center; justify-content: center;
  font-weight: 800; font-size: 1rem; letter-spacing: .02em;
}
.dev-name { font-weight: 800; font-size: 1.05rem; margin: 0; }
.dev-role { color: var(--text-muted); font-size: 0.85rem; margin: 2px 0 0; }
.dev-contact { display: flex; flex-direction: column; gap: var(--space-2); }
.dev-contact a {
  color: var(--text); text-decoration: none; font-size: 0.9rem; font-weight: 600;
}
.dev-contact a:hover { color: var(--accent); }
.dev-footer {
  border-top: 1px solid var(--border); margin: 0; padding-top: var(--space-3);
  color: var(--text-faint); font-size: 0.78rem; text-transform: uppercase;
  display: flex; align-items: center; justify-content: space-between; gap: var(--space-2); flex-wrap: wrap;
}
.dev-footer .btn {
  text-transform: none; font-weight: 500; font-size: 0.72rem;
  padding: 4px 6px; min-height: 28px;
}
.dev-update-status { margin: calc(-1 * var(--space-2)) 0 0; }

/* ---------- home (pantalla de inicio) ---------- */
.home-subtitle { margin-bottom: var(--space-4); }
.home-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: var(--space-3);
}
.home-card + .home-card { margin-top: 0; }
.home-card {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  text-decoration: none;
  color: var(--text);
  cursor: pointer;
  transition: border-color .15s, transform .1s;
}
.home-card:hover { border-color: var(--accent); }
.home-card:active { transform: scale(0.98); }
.home-card-icon {
  width: 44px; height: 44px; flex: 0 0 auto;
  border-radius: var(--radius-md);
  background: var(--accent-soft);
  color: var(--accent);
  display: flex; align-items: center; justify-content: center;
}
.home-card-body { display: flex; flex-direction: column; gap: 2px; min-width: 0; }
.home-card-title { font-weight: 700; font-size: 1rem; }
.home-card-desc { color: var(--text-muted); font-size: 0.82rem; }

/* ---------- forms ---------- */
.field { display: flex; flex-direction: column; gap: var(--space-1); margin-bottom: var(--space-4); }
.field label { font-size: 0.82rem; font-weight: 600; color: var(--text-muted); }
.field label.btn { font-size: 0.86rem; font-weight: 700; color: var(--text); }
.field label.checkbox-row { font-size: 0.88rem; font-weight: 400; }
.field .hint { font-size: 0.78rem; color: var(--text-faint); }
/* "Sugerir ejemplo" en el formulario de palabra */
.suggest-row { display: flex; justify-content: flex-end; margin-top: var(--space-2); }
.field .suggest-status { margin: var(--space-2) 0 0; color: var(--text-muted); }
.key-panel {
  margin-top: var(--space-3); padding: var(--space-3);
  border: 1px solid var(--border); border-radius: var(--radius-md); background: var(--bg-sunken);
  display: flex; flex-direction: column; gap: var(--space-2); align-items: flex-start;
}
.key-panel p { margin: 0; }
.key-panel .select-with-btn { width: 100%; }
.field-title { font-size: 0.82rem; font-weight: 600; color: var(--text-muted); }
.select-with-btn { display: flex; gap: var(--space-2); align-items: center; }
.select-with-btn select { flex: 1 1 auto; min-width: 0; }
.select-with-btn .btn { flex: 0 0 auto; }
input[type="text"], input[type="number"], input[type="search"], select, textarea {
  font: inherit;
  font-size: 0.95rem;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-strong);
  background: var(--bg-input);
  color: var(--text);
  width: 100%;
  min-height: 42px;
}
textarea { resize: vertical; }
select {
  appearance: none;
  -webkit-appearance: none;
  -moz-appearance: none;
  padding-right: 40px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' width='16' height='16' fill='none' stroke='%23aba79e' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 16px center;
  background-size: 16px 16px;
}
input:disabled, select:disabled { opacity: 0.55; }
input[type="checkbox"] { accent-color: var(--accent); }
.checkbox-row { display: flex; align-items: center; gap: var(--space-2); font-size: 0.88rem; color: var(--text-muted); }
.checkbox-row input[type="checkbox"] { width: 18px; height: 18px; flex: 0 0 auto; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--space-2);
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-strong);
  background: var(--bg-elevated);
  color: var(--text);
  font-family: inherit;
  font-weight: 700;
  font-size: 0.86rem;
  cursor: pointer;
  text-decoration: none;
  min-height: 42px;
}
.btn:hover { background: var(--bg-sunken); }
.btn-primary { background: var(--accent); border-color: var(--accent); color: var(--accent-contrast); }
.btn-primary:hover { background: var(--accent-strong); border-color: var(--accent-strong); }
.btn-danger { background: var(--danger-soft); border-color: var(--danger); color: var(--danger); }
.btn-danger:hover { background: var(--danger); color: #fff; }
.btn-ghost { background: transparent; border-color: transparent; }
.btn-ghost:hover { background: var(--bg-sunken); }
.btn-sm { padding: 6px 10px; font-size: 0.78rem; min-height: 32px; }
.btn-row { display: flex; gap: var(--space-3); flex-wrap: wrap; margin-top: var(--space-4); }
/* Botones lado a lado: sin salto de linea y con poco relleno lateral para
   que el texto quepa en una sola linea en el celular. */
.btn-row-equal .btn { flex: 1 1 0; white-space: nowrap; padding-left: 8px; padding-right: 8px; }
.btn[disabled] { opacity: 0.5; cursor: not-allowed; }

/* ---------- toolbar / tables ---------- */
.toolbar { display: flex; flex-direction: column; gap: var(--space-3); margin-bottom: var(--space-4); }
.toolbar-row { display: flex; gap: var(--space-3); flex-wrap: wrap; align-items: flex-end; }
.toolbar-row .field { margin-bottom: 0; min-width: 150px; flex: 1 1 150px; }
.toolbar-row .field.search { flex: 2 1 220px; }
.toolbar-row .btn-slot { display: flex; gap: var(--space-3); min-width: 150px; flex: 1 1 150px; }
.toolbar-row .btn-slot.search { flex: 2 1 220px; }
.toolbar-row .checkbox-row { padding-bottom: 10px; }
.btn-icon-only { padding-left: 10px; padding-right: 10px; }
.btn-shuffle-match { width: 50px; padding-left: 6px; padding-right: 6px; }

.row-count { color: var(--text-faint); font-size: 0.8rem; margin-bottom: var(--space-2); }
.row-count-split { display: flex; justify-content: space-between; align-items: baseline; gap: var(--space-2); }

/* overflow-y: hidden porque con overflow-x: auto el eje vertical pasa a
   "auto": la bocina de la ultima fila (44 px de alto con margen negativo)
   sobresale un par de pixeles y el contenedor se volvia desplazable en
   vertical, robandose el primer gesto de scroll de la pagina. */
.table-wrap { overflow-x: auto; overflow-y: hidden; border: 1px solid var(--border); border-radius: var(--radius-md); background: var(--bg-elevated); }
table { border-collapse: collapse; width: 100%; font-size: 0.86rem; }
thead th {
  text-align: left; padding: var(--space-3); background: var(--bg-sunken);
  color: var(--text-muted); font-weight: 700; font-size: 0.76rem; text-transform: uppercase; letter-spacing: .03em;
  white-space: nowrap;
}
tbody td { padding: var(--space-3); border-top: 1px solid var(--border); overflow-wrap: anywhere; }
th.col-center, td.col-center { text-align: center; }
tbody tr:hover { background: var(--bg-sunken); }
tbody tr.clickable { cursor: pointer; }
tbody tr.clickable:focus-visible { outline: 2px solid var(--focus-ring); outline-offset: -2px; }
tbody tr.clickable:active { background: var(--accent-soft); }

/* Traducir: opciones de Gemini, se elige tocando una */
.result-header { display: flex; justify-content: space-between; align-items: baseline; gap: var(--space-2); margin-bottom: var(--space-3); }
.translation-options { display: flex; flex-direction: column; gap: var(--space-2); }
.translation-option {
  display: flex; flex-direction: column; align-items: flex-start; gap: 2px; text-align: left;
  padding: var(--space-3); border: 1px solid var(--border-strong); border-radius: var(--radius-md);
  background: var(--bg-elevated); color: var(--text); font: inherit; cursor: pointer;
}
.translation-option:hover { background: var(--bg-sunken); }
.translation-option[aria-pressed="true"] { border-color: var(--accent); background: var(--accent-soft); box-shadow: inset 0 0 0 1px var(--accent); }

.empty-state { text-align: center; padding: var(--space-7) var(--space-4); color: var(--text-muted); }

.badge {
  display: inline-flex; align-items: center; padding: 3px 9px; border-radius: 999px;
  font-size: 0.72rem; font-weight: 700; background: var(--bg-sunken); color: var(--text-muted);
}
.badge-success { background: var(--accent); color: var(--accent-contrast); }

/* ---------- modal ---------- */
.modal-backdrop {
  position: fixed; inset: 0; background: rgba(15, 13, 11, 0.6);
  display: flex; align-items: center; justify-content: center; padding: var(--space-4);
  z-index: 100;
}
.modal-backdrop[hidden] { display: none; }
.modal {
  background: var(--bg-elevated); border-radius: var(--radius-lg); box-shadow: var(--shadow-lg);
  width: 100%; max-width: 480px; max-height: 90vh; overflow-y: auto; padding: var(--space-5);
}
.modal h2 { font-size: 1.1rem; }
.modal-actions { display: flex; justify-content: flex-end; gap: var(--space-3); margin-top: var(--space-5); }
.modal-actions--split { justify-content: space-between; flex-wrap: wrap; }
.modal-actions-group { display: flex; gap: var(--space-3); }

/* ---------- flashcards (Practicar) ---------- */
.flash-toolbar { display: flex; gap: var(--space-6); flex-wrap: wrap; align-items: flex-end; margin-bottom: var(--space-4); }
.flash-toolbar.gap-sm { gap: var(--space-3); }
.flash-toolbar .field { margin-bottom: 0; min-width: 150px; flex: 1 1 150px; }
.flash-toolbar .field-auto { min-width: 0; flex: 0 0 auto; margin-bottom: 0; }
.flash-toolbar .field.field-compact { margin-bottom: 0; min-width: 64px; flex: 0 1 90px; }
.flash-list { display: flex; flex-direction: column; gap: var(--space-3); }
.flash-card {
  background: var(--bg-elevated); border: 1px solid var(--border); border-radius: var(--radius-md);
  padding: var(--space-4); display: flex; align-items: center; gap: var(--space-4); flex-wrap: wrap;
}
.flash-card .flash-main { flex: 1 1 220px; min-width: 0; }
.flash-card .flash-primary { font-size: 1.05rem; font-weight: 700; }
.flash-card .flash-secondary { color: var(--accent-strong); font-weight: 600; margin-top: 2px; }
.flash-card .flash-context { color: var(--text-muted); font-size: 0.82rem; font-style: italic; margin-top: 4px; }
.flash-card .flash-actions { display: flex; align-items: center; gap: var(--space-3); flex: 0 0 auto; }
.flash-card.pending { border-color: var(--warning); }
.flash-card .flash-primary, .flash-card .flash-secondary { display: flex; align-items: center; gap: var(--space-1); }
.flash-card .flash-secondary[hidden] { display: none; }
/* Bocina de pronunciacion: discreta, pero con area tactil de 44x44 px; el
   margen negativo evita que agrande la altura de la linea. */
.speak-btn {
  flex: 0 0 auto;
  width: 44px; height: 44px;
  margin: -10px 0;
  border: none; border-radius: var(--radius-sm);
  background: transparent;
  color: var(--text-muted);
  display: inline-flex; align-items: center; justify-content: center;
  cursor: pointer;
}
.speak-btn:hover { background: var(--bg-sunken); color: var(--accent-strong); }
.speak-btn:active { color: var(--accent-strong); }
/* Columna de la bocina en Palabras (sin titulo). Boton de 26 px de ancho
   (no 44) para no comerle espacio a las palabras; conserva 44 px de alto
   con margen negativo para no agrandar la fila. Con el relleno reducido de
   la columna siguiente, el icono (18 px) queda centrado: 8 px al borde de
   la tabla y 8 px a la palabra. Color mas tenue para distinguirlo del
   texto de las palabras. */
th.col-speak, td.col-speak { width: 1%; padding: 0 0 0 var(--space-1); }
td.col-speak .speak-btn { width: 26px; margin: -14px 0; vertical-align: middle; color: var(--text-faint); }
td.col-speak .speak-btn:hover, td.col-speak .speak-btn:active { color: var(--accent-strong); }
th.col-after-speak, td.col-after-speak { padding-left: var(--space-1); }
/* Columna que se ajusta a su contenido (el titulo) en vez de recibir parte
   del ancho sobrante: ese ancho pasa a Ingles y Espanol. */
th.col-shrink, td.col-shrink { width: 1%; }
/* Entre Espanol y Aprendida no hace falta margen: Aprendida solo muestra
   Si/No centrado bajo un titulo mucho mas ancho, asi que el texto en
   espanol puede llegar hasta el borde sin chocar con nada. */
th.col-before-shrink, td.col-before-shrink { padding-right: 0; }
th.col-shrink, td.col-shrink { padding-left: 0; }
.btn-reveal { min-width: 84px; }

.toggle-row { display: flex; align-items: center; gap: var(--space-2); font-size: 0.85rem; font-weight: 600; }
.toggle-switch { position: relative; width: 40px; height: 22px; flex: 0 0 auto; }
.toggle-switch input { opacity: 0; width: 100%; height: 100%; margin: 0; cursor: pointer; }
.toggle-switch .track {
  position: absolute; inset: 0; background: var(--border-strong); border-radius: 999px; transition: background .15s;
}
.toggle-switch .thumb {
  position: absolute; top: 2px; left: 2px; width: 18px; height: 18px; background: #fff; border-radius: 50%;
  transition: transform .15s; box-shadow: var(--shadow-sm);
}
.toggle-switch input:checked ~ .track { background: var(--accent); }
.toggle-switch input:checked ~ .thumb { transform: translateX(18px); }

/* ---------- examen ---------- */
.quiz-row {
  background: var(--bg-elevated); border: 1px solid var(--border); border-radius: var(--radius-md);
  padding: var(--space-4); display: flex; flex-direction: column; gap: var(--space-2);
}
.quiz-row.correct { border-color: var(--success); background: var(--success-soft); }
.quiz-row.incorrect { border-color: var(--danger); background: var(--danger-soft); }
.quiz-row .quiz-prompt {
  font-weight: 700; display: flex; align-items: center; gap: var(--space-2); flex-wrap: wrap;
}
.quiz-row .quiz-correct { font-weight: 600; font-size: 0.88rem; color: var(--text-muted); }
.quiz-row.correct .quiz-correct { color: var(--success); }
.quiz-row.incorrect .quiz-correct { color: var(--danger); }
.quiz-row .quiz-answer-row { display: flex; gap: var(--space-2); align-items: center; flex-wrap: wrap; }
.quiz-row .quiz-answer-row input { flex: 1 1 200px; }
.quiz-score { font-weight: 800; font-size: 1.1rem; white-space: nowrap; }
.quiz-result-row { display: flex; align-items: center; gap: var(--space-3); flex: 0 0 auto; margin-left: auto; align-self: flex-end; }

@media (max-width: 720px) {
  .content { padding: var(--space-4); }
  .flash-card { flex-direction: column; align-items: stretch; }
  .flash-card .flash-main { flex: 1 1 auto; }
  .flash-card .flash-actions { justify-content: space-between; }
}

@media (max-width: 480px) {
  .toolbar-row .field { min-width: 0; flex: 1 1 0; }
  .toolbar-row .field.search { flex: 1.3 1 0; }
  .toolbar-row .btn-slot { min-width: 0; flex: 1 1 0; gap: var(--space-2); }
  .toolbar-row .btn-slot.search { flex: 1.3 1 0; }
  .toolbar-row { gap: var(--space-2); }
  .toolbar-row .btn { padding-left: 10px; padding-right: 10px; }
  .flash-toolbar { gap: 40px; }
  .flash-toolbar.gap-sm { gap: var(--space-2); }
  .flash-toolbar .field { min-width: 0; flex: 1 1 0; }
  .quiz-score { font-size: 0.95rem; }
}

@media print {
  .topbar, .topnav, .btn-row { display: none !important; }
  .content { max-width: none; padding: 0; }
}