:root {
  --bg: oklch(97% 0.01 250);
  --surface: oklch(100% 0 0);
  --fg: oklch(20% 0.02 250);
  --muted: oklch(50% 0.02 250);
  --border: oklch(88% 0.01 250);
  --accent: oklch(58% 0.18 255);
  --accent-fg: oklch(100% 0 0);
  --success: oklch(55% 0.14 145);
  --warn: oklch(70% 0.16 80);
  --card-shadow: 0 1px 3px oklch(0% 0 0 / 0.08);
  --radius: 12px;
  --font-display: -apple-system, BlinkMacSystemFont, 'SF Pro Display', system-ui, sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, 'SF Pro Text', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', 'SF Mono', ui-monospace, monospace;
}

[data-theme="dark"] {
  --bg: oklch(15% 0.02 250);
  --surface: oklch(20% 0.02 250);
  --fg: oklch(92% 0.01 250);
  --muted: oklch(60% 0.02 250);
  --border: oklch(30% 0.02 250);
  --accent: oklch(68% 0.16 255);
  --accent-fg: oklch(10% 0 0);
  --success: oklch(65% 0.14 145);
  --warn: oklch(75% 0.16 80);
  --card-shadow: 0 1px 3px oklch(0% 0 0 / 0.3);
}

[data-theme="eink"] {
  --bg: oklch(98% 0 0);
  --surface: oklch(100% 0 0);
  --fg: oklch(0% 0 0);
  --muted: oklch(30% 0 0);
  --border: oklch(0% 0 0);
  --accent: oklch(0% 0 0);
  --accent-fg: oklch(100% 0 0);
  --success: oklch(30% 0 0);
  --warn: oklch(50% 0 0);
  --card-shadow: none;
  --radius: 4px;
}

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

html { font-size: 16px; }

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--fg);
  line-height: 1.6;
  min-height: 100vh;
  transition: background 0.3s, color 0.3s;
}

[data-theme="eink"] body {
  font-size: 18px;
  line-height: 1.8;
}

.app {
  max-width: 960px;
  margin: 0 auto;
  padding: 24px 16px;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 0;
  margin-bottom: 24px;
  border-bottom: 2px solid var(--border);
}

[data-theme="eink"] header {
  border-bottom-width: 3px;
}

.logo {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--fg);
  text-decoration: none;
}

.logo:hover { color: var(--accent); }

.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--fg);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-decoration: none;
  transition: all 0.2s ease;
}

.back-btn:hover {
  background: var(--accent);
  color: var(--accent-fg);
  border-color: var(--accent);
}

[data-theme="eink"] .back-btn {
  border-width: 2px;
  font-weight: 600;
}

.theme-toggle {
  display: flex;
  gap: 4px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 4px;
}

[data-theme="eink"] .theme-toggle {
  border-width: 2px;
}

.theme-btn {
  padding: 8px 12px;
  border: none;
  background: transparent;
  color: var(--muted);
  font-size: 0.85rem;
  font-weight: 500;
  border-radius: calc(var(--radius) - 4px);
  cursor: pointer;
  transition: all 0.2s;
}

.theme-btn:hover { color: var(--fg); }

.theme-btn.active {
  background: var(--accent);
  color: var(--accent-fg);
}

[data-theme="eink"] .theme-btn.active {
  background: var(--fg);
  color: var(--bg);
}

.progress-bar {
  width: 100%;
  height: 8px;
  background: var(--border);
  border-radius: 4px;
  margin-bottom: 24px;
  overflow: hidden;
}

[data-theme="eink"] .progress-bar {
  height: 12px;
  border: 2px solid var(--fg);
}

.progress-fill {
  height: 100%;
  background: var(--accent);
  border-radius: 4px;
  transition: width 0.4s ease;
}

[data-theme="eink"] .progress-fill {
  background: var(--fg);
}

.progress-text {
  font-size: 0.85rem;
  color: var(--muted);
  margin-bottom: 8px;
  font-variant-numeric: tabular-nums;
}

.nav-blocks {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

.nav-btn {
  padding: 8px 16px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--fg);
  font-size: 0.85rem;
  font-weight: 500;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.2s;
}

[data-theme="eink"] .nav-btn {
  border-width: 2px;
  font-size: 1rem;
}

.nav-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.nav-btn.active {
  background: var(--accent);
  color: var(--accent-fg);
  border-color: var(--accent);
}

[data-theme="eink"] .nav-btn.active {
  background: var(--fg);
  color: var(--bg);
  border-color: var(--fg);
}

.block {
  display: none;
}

.block.active {
  display: block;
}

.block-title {
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--fg);
}

.block-desc {
  color: var(--muted);
  margin-bottom: 24px;
  font-size: 0.95rem;
}

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

.word-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 20px;
  box-shadow: var(--card-shadow);
  transition: all 0.2s;
  position: relative;
}

[data-theme="eink"] .word-card {
  border-width: 2px;
  box-shadow: none;
  padding: 20px 24px;
}

.word-card:hover {
  border-color: var(--accent);
}

.word-card.learned {
  border-left: 4px solid var(--success);
}

[data-theme="eink"] .word-card.learned {
  border-left-width: 6px;
}

.word-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 8px;
}

/* Escritura real: principal (cómo se escribe). */
.word-main {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--fg);
}

[data-theme="eink"] .word-main {
  font-size: 1.5rem;
}

.word-translation {
  font-size: 0.95rem;
  color: var(--muted);
  font-style: italic;
}

.word-num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--muted);
  background: var(--bg);
  padding: 2px 8px;
  border-radius: 4px;
  font-variant-numeric: tabular-nums;
}

.word-examples {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
  display: none;
}

.word-card.expanded .word-examples {
  display: block;
}

.example {
  font-size: 0.9rem;
  color: var(--fg);
  margin-bottom: 10px;
  padding-left: 12px;
  border-left: 2px solid var(--accent);
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

[data-theme="eink"] .example {
  border-left-width: 3px;
  font-size: 1rem;
}

.example-body {
  display: block;
}

/* === Jerarquía de lectura ===
   La ESCRITURA real es lo principal (grande, color normal).
   La PRONUNCIACIÓN va debajo: secundaria pero llamativa (color de acento, negrita).
   La traducción al español queda como apoyo. */

/* Pronunciación — debajo, secundaria pero destacada en color */
.word-pron,
.example-pron {
  color: var(--accent);
  font-weight: 700;
  font-family: var(--font-display);
}

.word-pron {
  display: block;
  font-size: 1rem;
  margin-top: 2px;
}

.example-pron {
  display: block;
  font-size: 0.92rem;
  line-height: 1.3;
  margin-top: 1px;
}

[data-theme="eink"] .word-pron,
[data-theme="eink"] .example-pron {
  color: var(--fg);
  text-decoration: underline;
}

/* Escritura real del ejemplo — principal */
.example-target {
  display: block;
  font-size: 0.95rem;
  color: var(--fg);
  font-weight: 500;
}

.example-es {
  display: block;
  color: var(--muted);
  font-style: normal;
  font-size: 0.85rem;
  margin-top: 2px;
}

.ex-speak {
  flex: none;
  margin-top: 1px;
  padding: 2px 7px;
  font-size: 0.7rem;
  line-height: 1.2;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--accent);
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s;
}

.ex-speak:hover {
  border-color: var(--accent);
  background: var(--accent);
  color: var(--accent-fg);
}

[data-theme="eink"] .ex-speak {
  border-width: 2px;
  font-size: 0.8rem;
}

.word-actions {
  display: flex;
  gap: 8px;
  margin-top: 12px;
}

.btn {
  padding: 6px 12px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--fg);
  font-size: 0.8rem;
  font-weight: 500;
  border-radius: calc(var(--radius) - 4px);
  cursor: pointer;
  transition: all 0.2s;
}

[data-theme="eink"] .btn {
  border-width: 2px;
  font-size: 0.95rem;
  padding: 8px 16px;
}

.btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.btn-learn {
  background: var(--success);
  color: var(--accent-fg);
  border-color: var(--success);
}

[data-theme="eink"] .btn-learn {
  background: var(--fg);
  color: var(--bg);
  border-color: var(--fg);
}

.btn-learn:hover {
  opacity: 0.85;
  color: var(--accent-fg);
}

.btn-speak {
  padding: 6px 10px;
  line-height: 1;
}

.btn-speak:hover {
  border-color: var(--accent);
}

[data-theme="eink"] .btn-speak {
  padding: 8px 12px;
}

/* --- Foco visible accesible (los 3 temas) --- */
:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
  border-radius: calc(var(--radius) - 4px);
}

[data-theme="eink"] :focus-visible {
  outline-width: 4px;
}

.grammar-section {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 16px;
}

[data-theme="eink"] .grammar-section {
  border-width: 2px;
  padding: 28px;
}

.grammar-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--fg);
}

.pron-legend {
  font-size: 0.8rem;
  color: var(--muted);
  margin: 8px 0 4px;
}

.pron-legend-pron {
  color: var(--accent);
  font-weight: 800;
  font-family: var(--font-display);
}

.pron-legend-write {
  font-style: italic;
  color: var(--muted);
}

[data-theme="eink"] .pron-legend-pron {
  color: var(--fg);
  text-decoration: underline;
}

.grammar-examples {
  margin-top: 16px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
}

.grammar-examples-label {
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--muted);
  margin-bottom: 8px;
}

.grammar-content {
  color: var(--fg);
  font-size: 0.95rem;
  line-height: 1.7;
}

[data-theme="eink"] .grammar-content {
  font-size: 1.1rem;
  line-height: 1.9;
}

.grammar-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 12px 0;
  font-size: 0.85rem;
}

[data-theme="eink"] .grammar-content table {
  font-size: 1rem;
}

.grammar-content th,
.grammar-content td {
  padding: 8px 12px;
  text-align: left;
  border: 1px solid var(--border);
}

[data-theme="eink"] .grammar-content th,
[data-theme="eink"] .grammar-content td {
  border-width: 2px;
  padding: 10px 14px;
}

.grammar-content th {
  background: var(--bg);
  font-weight: 600;
}

.grammar-content code {
  font-family: var(--font-mono);
  background: var(--bg);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.85em;
}

.grammar-content strong {
  color: var(--accent);
}

[data-theme="eink"] .grammar-content strong {
  color: var(--fg);
  text-decoration: underline;
  text-decoration-thickness: 2px;
}

.controls {
  display: flex;
  gap: 12px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.search-box {
  flex: 1;
  min-width: 200px;
  padding: 10px 16px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--fg);
  font-size: 0.95rem;
  border-radius: var(--radius);
  outline: none;
  transition: border-color 0.2s;
}

[data-theme="eink"] .search-box {
  border-width: 2px;
  font-size: 1.1rem;
  padding: 12px 18px;
}

.search-box:focus {
  border-color: var(--accent);
}

.filter-btn {
  padding: 10px 16px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--fg);
  font-size: 0.85rem;
  font-weight: 500;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.2s;
}

[data-theme="eink"] .filter-btn {
  border-width: 2px;
  font-size: 1rem;
}

.filter-btn.active {
  background: var(--accent);
  color: var(--accent-fg);
  border-color: var(--accent);
}

[data-theme="eink"] .filter-btn.active {
  background: var(--fg);
  color: var(--bg);
  border-color: var(--fg);
}

@media (max-width: 640px) {
  .app { padding: 16px 12px; }
  .block-title { font-size: 1.4rem; }
  .word-main { font-size: 1.1rem; }
  .nav-blocks { gap: 6px; }
  .nav-btn { padding: 6px 12px; font-size: 0.8rem; }
}