/* Deutsch lernen — lesson UI */
:root {
  --de-red: #cf1322;
  --de-gold: #ffcc00;
  --de-black: #141414;
  --de-formal: #1677ff;
  --de-informal: #389e0d;
  --de-bg: #f4f2ee;
  --de-card: #fff;
  --de-muted: rgba(0, 0, 0, 0.55);
  --de-radius: 14px;
  --de-shadow: 0 4px 24px rgba(20, 20, 20, 0.07);
  --nav-h: 52px;
}

body {
  background: var(--de-bg);
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  color: var(--de-black);
}

/* ?? Header ?? */
.lesson-shell header {
  background: linear-gradient(135deg, #141414 0%, #3d3d3d 50%, var(--de-red) 100%);
  color: #fff;
  padding: 28px 20px 32px;
  margin-bottom: 0;
}

.lesson-shell header h1 {
  color: #fff;
  margin: 0 0 8px;
  font-size: clamp(1.35rem, 4vw, 1.75rem);
  line-height: 1.2;
}

.lesson-shell header p {
  margin: 4px 0 0;
  opacity: 0.92;
  max-width: 42rem;
}

.lesson-shell .badge {
  background: var(--de-gold);
  color: var(--de-black);
  border: none;
  font-weight: 700;
  letter-spacing: 0.04em;
}

/* ?? Sticky section nav ?? */
.lesson-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid #e8e4de;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
}

.lesson-nav-inner {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 12px;
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: var(--nav-h);
  overflow-x: auto;
  scrollbar-width: none;
}

.lesson-nav-inner::-webkit-scrollbar {
  display: none;
}

.lesson-nav-back {
  flex-shrink: 0;
  color: var(--de-formal);
  font-weight: 600;
  text-decoration: none;
  font-size: 0.85rem;
  padding: 6px 10px;
  border-radius: 8px;
}

.lesson-nav-back:hover {
  background: #f0f5ff;
}

.lesson-tabs {
  display: flex;
  gap: 4px;
  flex: 1;
  min-width: 0;
}

.lesson-tab {
  flex-shrink: 0;
  padding: 8px 14px;
  border-radius: 999px;
  font-size: 0.82rem;
  font-weight: 600;
  text-decoration: none;
  color: var(--de-muted);
  border: 1px solid transparent;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}

.lesson-tab:hover {
  color: var(--de-black);
  background: #f5f2ed;
}

.lesson-tab.is-active {
  color: var(--de-red);
  background: #fff1f0;
  border-color: #ffa39e;
}

.lesson-pager {
  max-width: 960px;
  margin: 32px auto 48px;
  padding: 0 16px;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 12px;
}

.lesson-pager-link {
  color: var(--de-formal);
  font-weight: 600;
  text-decoration: none;
  font-size: 0.9rem;
  padding: 10px 14px;
  border-radius: 10px;
  background: var(--de-card);
  box-shadow: var(--de-shadow);
  border: 1px solid #e8e4de;
}

.lesson-pager-link:hover {
  background: #f0f5ff;
}

.lesson-pager-spacer {
  display: block;
}

.lesson-pager-home {
  color: var(--de-muted);
  font-weight: 600;
  text-decoration: none;
  font-size: 0.85rem;
  text-align: center;
  white-space: nowrap;
}

.lesson-pager-home:hover {
  color: var(--de-formal);
}

@media (max-width: 560px) {
  .lesson-pager {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .lesson-pager-link {
    justify-self: stretch;
    text-align: center;
  }
}

/* ?? Main layout ?? */
.lesson-shell main {
  max-width: 960px;
  padding: 20px 16px 72px;
}

.lesson-section {
  margin: 28px 0 40px;
  scroll-margin-top: calc(var(--nav-h) + 16px);
}

.lesson-section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.lesson-section-head h2 {
  margin: 0;
  font-size: 1.25rem;
  font-weight: 700;
  border-bottom: 3px solid var(--de-gold);
  padding-bottom: 6px;
  flex: 1;
  min-width: 180px;
}

.section-toggle {
  border: 1px solid #d9d9d9;
  background: #fff;
  border-radius: 999px;
  padding: 6px 14px;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  color: var(--de-muted);
}

.section-toggle:hover {
  border-color: var(--de-red);
  color: var(--de-red);
}

.lesson-section.is-collapsed .lesson-section-body {
  display: none;
}

/* ?? Toolbar: search + filters ?? */
.lesson-toolbar {
  background: var(--de-card);
  border-radius: var(--de-radius);
  padding: 14px 16px;
  margin-bottom: 16px;
  box-shadow: var(--de-shadow);
  border: 1px solid #eee;
}

.vocab-search-wrap {
  position: relative;
  margin-bottom: 12px;
}

.vocab-search {
  width: 100%;
  padding: 10px 14px 10px 38px;
  border: 1px solid #d9d9d9;
  border-radius: 10px;
  font-size: 1rem;
  background: #fafafa url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='18' height='18' fill='%23999' viewBox='0 0 16 16'%3E%3Cpath d='M11.742 10.344a6.5 6.5 0 1 0-1.397 1.398h-.001l3.85 3.85a1 1 0 0 0 1.415-1.414l-3.85-3.85zm-5.242 1.156a5 5 0 1 1 0-10 5 5 0 0 1 0 10z'/%3E%3C/svg%3E") no-repeat 12px center;
}

.vocab-search:focus {
  outline: none;
  border-color: var(--de-formal);
  box-shadow: 0 0 0 2px rgba(22, 119, 255, 0.15);
}

.filter-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: center;
}

.filter-chip {
  border: 1px solid #e0e0e0;
  background: #fafafa;
  border-radius: 999px;
  padding: 5px 12px;
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  color: var(--de-muted);
  transition: all 0.15s;
}

.filter-chip:hover {
  border-color: #bbb;
  color: var(--de-black);
}

.filter-chip.is-active {
  background: var(--de-black);
  color: #fff;
  border-color: var(--de-black);
}

.filter-chip[data-filter="familia"].is-active { background: #722ed1; border-color: #722ed1; }
.filter-chip[data-filter="paises"].is-active { background: #13c2c2; border-color: #13c2c2; }
.filter-chip[data-filter="saludos"].is-active { background: #fa8c16; border-color: #fa8c16; }
.filter-chip[data-filter="verbos"].is-active { background: #389e0d; border-color: #389e0d; }
.filter-chip[data-filter="preguntas"].is-active { background: #1677ff; border-color: #1677ff; }

.vocab-count {
  margin-left: auto;
  font-size: 0.78rem;
  color: var(--de-muted);
  font-weight: 500;
}

.vocab-empty {
  text-align: center;
  padding: 32px 16px;
  color: var(--de-muted);
  font-style: italic;
  background: #fafafa;
  border-radius: var(--de-radius);
  border: 1px dashed #ddd;
}

/* ?? Vocab cards grid ?? */
.vocab-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 12px;
}

.vocab-card {
  background: var(--de-card);
  border-radius: var(--de-radius);
  padding: 14px 16px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
  border: 1px solid #f0f0f0;
  border-left: 4px solid var(--de-gold);
  transition: transform 0.12s, box-shadow 0.12s;
}

.vocab-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--de-shadow);
}

.vocab-card[data-category="familia"] { border-left-color: #722ed1; }
.vocab-card[data-category="paises"] { border-left-color: #13c2c2; }
.vocab-card[data-category="saludos"] { border-left-color: #fa8c16; }
.vocab-card[data-category="verbos"] { border-left-color: #389e0d; }
.vocab-card[data-category="preguntas"] { border-left-color: #1677ff; }

.vocab-card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 4px;
}

.vocab-cat-tag {
  font-size: 0.65rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 2px 8px;
  border-radius: 999px;
  background: #f5f5f5;
  color: var(--de-muted);
  flex-shrink: 0;
}

.vocab-card[data-category="familia"] .vocab-cat-tag { background: #f9f0ff; color: #722ed1; }
.vocab-card[data-category="paises"] .vocab-cat-tag { background: #e6fffb; color: #08979c; }
.vocab-card[data-category="saludos"] .vocab-cat-tag { background: #fff7e6; color: #d46b08; }
.vocab-card[data-category="verbos"] .vocab-cat-tag { background: #f6ffed; color: #389e0d; }
.vocab-card[data-category="preguntas"] .vocab-cat-tag { background: #e6f4ff; color: #1677ff; }

.vocab-card .de {
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1.35;
}

.vocab-card .es {
  color: var(--de-muted);
  margin-top: 4px;
  font-size: 0.95rem;
}

.vocab-card .pron {
  font-size: 0.85rem;
  color: #8b4513;
  margin-top: 8px;
  font-style: italic;
}

.vocab-card .tip {
  font-size: 0.8rem;
  color: var(--de-muted);
  margin: 8px 0 0;
  padding-top: 8px;
  border-top: 1px dashed #eee;
}

/* ?? Gallery ?? */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 10px;
}

.gallery-grid a {
  display: block;
  border-radius: 10px;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  aspect-ratio: 4/3;
}

.gallery-grid img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* ?? Grammar ?? */
.grammar-grid {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.grammar-block {
  background: var(--de-card);
  padding: 18px 20px;
  border-radius: var(--de-radius);
  box-shadow: var(--de-shadow);
  border: 1px solid #f0f0f0;
}

.grammar-block h3 {
  margin: 0 0 8px;
  font-size: 1.05rem;
  color: var(--de-red);
}

.grammar-block p {
  margin: 0 0 12px;
  color: var(--de-muted);
  line-height: 1.55;
}

.grammar-block ul {
  margin: 0;
  padding-left: 0;
  list-style: none;
}

.grammar-block li {
  padding: 8px 0;
  border-bottom: 1px solid #f5f5f5;
  line-height: 1.45;
}

.grammar-block li:last-child {
  border-bottom: none;
}

/* ?? Practice ?? */
.practice-toolbar {
  margin-bottom: 12px;
}

.practice-toggle {
  border: none;
  background: var(--de-red);
  color: #fff;
  font-weight: 700;
  padding: 10px 18px;
  border-radius: 999px;
  cursor: pointer;
  font-size: 0.88rem;
  box-shadow: 0 4px 12px rgba(207, 19, 34, 0.25);
}

.practice-toggle:hover {
  background: #a8071a;
}

.practice-list details {
  background: var(--de-card);
  border-radius: 12px;
  margin: 8px 0;
  padding: 0;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
  border: 1px solid #f0f0f0;
  overflow: hidden;
}

.practice-list summary {
  cursor: pointer;
  font-weight: 600;
  padding: 14px 16px;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 10px;
}

.practice-list summary::-webkit-details-marker {
  display: none;
}

.practice-list summary::before {
  content: "?";
  color: var(--de-red);
  font-size: 0.9rem;
  transition: transform 0.15s;
}

.practice-list details[open] summary::before {
  transform: rotate(90deg);
}

.practice-list .answer {
  padding: 0 16px 14px;
  margin: 0;
  border-top: 1px solid #f5f5f5;
  padding-top: 12px;
}

/* ?? Dialog section ?? */
.vocab-dialog-section {
  margin-top: 8px;
}

.dialog-toolbar {
  margin-bottom: 12px;
}

.dialog-expand-btn {
  border: 1px solid #d9d9d9;
  background: #fff;
  border-radius: 8px;
  padding: 8px 14px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
}

.dialog-expand-btn:hover {
  border-color: var(--de-formal);
  color: var(--de-formal);
}

.vocab-dialog-heading {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--de-muted);
  margin: 0 0 12px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

#vocab-dialog-root .ant-collapse-item {
  margin-bottom: 10px;
  border: 1px solid #f0f0f0 !important;
  border-radius: 12px !important;
  overflow: hidden;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
  background: #fff;
}

#vocab-dialog-root .ant-collapse-header {
  align-items: center !important;
  padding: 14px 16px !important;
}

#vocab-dialog-root .ant-collapse-content-box {
  padding: 4px 16px 20px !important;
}

.dialog-panel-label {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: rgba(0, 0, 0, 0.45);
  margin-bottom: 10px;
}

.dialog-de-text {
  margin: 0 0 4px !important;
  font-size: 18px !important;
}

.dialog-pron-text {
  display: block;
  font-size: 13px;
  color: #8b4513;
  font-style: italic;
  margin-bottom: 8px;
}

.dialog-answer-es {
  display: block;
  color: rgba(0, 0, 0, 0.55);
  margin-bottom: 6px;
}

.dialog-formal-card {
  border-color: #91caff !important;
  background: linear-gradient(180deg, #fafcff 0%, #f0f7ff 100%);
}

.dialog-informal-card {
  border-color: #b7eb8f !important;
  background: linear-gradient(180deg, #fcfffa 0%, #f6ffed 100%);
}

.dialog-tip {
  margin-top: 8px;
  font-size: 13px;
  color: rgba(0, 0, 0, 0.45);
}

/* Speak buttons (shared) */
.speak {
  border: none;
  background: #f0ebe3;
  cursor: pointer;
  border-radius: 999px;
  min-width: 32px;
  height: 32px;
  padding: 0 8px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  vertical-align: middle;
  transition: transform 0.15s, background 0.15s;
  color: inherit;
}

.speak-tag {
  font-size: 0.62rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  line-height: 1;
}

.speak svg {
  width: 15px;
  height: 15px;
  flex-shrink: 0;
}

.speak:hover {
  transform: scale(1.08);
  background: var(--de-gold);
}

.speak.speaking {
  background: var(--de-red);
  color: #fff;
}

.empty {
  color: var(--de-muted);
  font-style: italic;
}

@media (max-width: 600px) {
  .vocab-grid {
    grid-template-columns: 1fr;
  }
  .lesson-tab {
    padding: 7px 11px;
    font-size: 0.78rem;
  }
}