:root {
  --bg: #fbfaf7;
  --fg: #1d1c1a;
  --muted: #6b6760;
  --accent: #2f6f4f;
  --accent-soft: #e3f0e8;
  --sep: #b5651d;
  --sep-soft: #f6e6d6;
  --card: #ffffff;
  --surface-2: #f1efe9;
  --border: #e3ded5;
  --shadow: 0 6px 24px rgba(0, 0, 0, 0.12);
  --hl-new-bg: #fff7d6;
  --hl-new-line: #f0d264;
  --hl-learn-bg: #e2eefb;
  --hl-learn-line: #7fb0e6;
  --warn-bg: #fff4e5;
  --warn-border: #f0c98a;
  --warn-fg: #7a4a00;
  color-scheme: light;
  font-family:
    "Segoe UI",
    system-ui,
    -apple-system,
    sans-serif;
}

/* Dark palette — applied when theme is explicitly "dark", or "auto" + OS dark. */
:root[data-theme="dark"] {
  --bg: #15171a;
  --fg: #e8e6e1;
  --muted: #9a958c;
  --accent: #5aa17a;
  --accent-soft: #1e3a2c;
  --sep: #d08a4e;
  --sep-soft: #3a2a1c;
  --card: #1e2227;
  --surface-2: #262b31;
  --border: #2c3138;
  --shadow: 0 6px 24px rgba(0, 0, 0, 0.5);
  --hl-new-bg: #3a3413;
  --hl-new-line: #8a7a2c;
  --hl-learn-bg: #1c2c3f;
  --hl-learn-line: #3f6a99;
  --warn-bg: #3a2e1a;
  --warn-border: #6a541f;
  --warn-fg: #f0c98a;
  color-scheme: dark;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]):not([data-theme="dark"]) {
    --bg: #15171a;
    --fg: #e8e6e1;
    --muted: #9a958c;
    --accent: #5aa17a;
    --accent-soft: #1e3a2c;
    --sep: #d08a4e;
    --sep-soft: #3a2a1c;
    --card: #1e2227;
    --surface-2: #262b31;
    --border: #2c3138;
    --shadow: 0 6px 24px rgba(0, 0, 0, 0.5);
    --hl-new-bg: #3a3413;
    --hl-new-line: #8a7a2c;
    --hl-learn-bg: #1c2c3f;
    --hl-learn-line: #3f6a99;
    --warn-bg: #3a2e1a;
    --warn-border: #6a541f;
    --warn-fg: #f0c98a;
    color-scheme: dark;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.6;
}

.app-header {
  padding: 1.5rem 2rem 0.5rem;
}
.app-header h1 {
  margin: 0;
  color: var(--accent);
  letter-spacing: -0.02em;
}
.tagline {
  margin: 0.25rem 0 0;
  color: var(--muted);
}

.reader {
  max-width: 760px;
  margin: 1rem auto;
  padding: 0 2rem;
}

.banner {
  background: var(--warn-bg);
  border: 1px solid var(--warn-border);
  color: var(--warn-fg);
  padding: 0.6rem 0.9rem;
  border-radius: 8px;
  margin-bottom: 1rem;
  font-size: 0.9rem;
}
.hidden {
  display: none;
}

.input-row {
  display: flex;
  gap: 0.75rem;
  align-items: stretch;
  margin-bottom: 1.25rem;
}
textarea {
  flex: 1;
  font: inherit;
  padding: 0.75rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  resize: vertical;
  background: var(--card);
}
button {
  font: inherit;
  font-weight: 600;
  padding: 0 1.25rem;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 10px;
  cursor: pointer;
}
button:hover {
  filter: brightness(1.05);
}

.reader-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.75rem;
}
.stats {
  color: var(--muted);
  font-size: 0.85rem;
}
.token.speaking {
  background: var(--accent);
  color: #fff;
  border-radius: 4px;
}

.output {
  font-size: 1.25rem;
}
.sentence {
  margin: 0 0 0.75rem;
}

.token {
  cursor: pointer;
  border-radius: 4px;
  padding: 0 1px;
  transition: background 0.12s;
}
.token:hover {
  background: var(--accent-soft);
}
.token.sep-verb {
  text-decoration: underline dotted var(--sep);
  text-underline-offset: 3px;
}

/* Vocabulary status highlighting. Known/ignored words are left plain so the
   overlay recedes as the learner progresses (charter pillar #6). */
.token.status-new {
  background: var(--hl-new-bg);
  box-shadow: inset 0 -2px 0 var(--hl-new-line);
}
.token.status-learning {
  background: var(--hl-learn-bg);
  box-shadow: inset 0 -2px 0 var(--hl-learn-line);
}
.token.status-known,
.token.status-ignored {
  background: transparent;
  box-shadow: none;
}
.token.status-ignored {
  color: var(--muted);
}

/* Adaptive overlay verbosity (M13): soften/suppress highlighting as the learner
   advances. `full` keeps the defaults above; `medium` reduces the Learning highlight to
   just the underline; `minimal` flags only genuinely new words. */
.output.overlay-medium .token.status-learning {
  background: transparent;
}
.output.overlay-minimal .token.status-learning {
  background: transparent;
  box-shadow: none;
}

.difficulty-badge {
  font-size: 0.85rem;
  color: var(--fg);
}

.popover {
  position: absolute;
  z-index: 20;
  min-width: 200px;
  max-width: 320px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
  box-shadow: var(--shadow);
  padding: 0.75rem 0.9rem;
  font-size: 0.95rem;
}
.pop-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.5rem;
}
.pop-head strong {
  font-size: 1.15rem;
}
.pop-pos {
  color: var(--muted);
  font-size: 0.8rem;
  font-style: italic;
}
.pop-lemma {
  margin-top: 0.35rem;
}
.pop-gloss {
  margin-top: 0.35rem;
  font-size: 1.05rem;
}
.pop-gloss.muted {
  color: var(--muted);
  font-style: italic;
  font-size: 0.9rem;
}
.pop-morph {
  margin-top: 0.35rem;
  color: var(--accent);
  font-size: 0.85rem;
}
.pop-actions {
  display: flex;
  gap: 0.4rem;
  margin-top: 0.6rem;
}
.pop-actions button {
  flex: 1;
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.3rem 0;
  background: var(--surface-2);
  color: var(--fg);
  border: 1px solid var(--border);
  border-radius: 7px;
  cursor: pointer;
}
.pop-actions button:hover {
  background: var(--accent-soft);
}
.pop-actions button.on {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}
.tag {
  background: var(--sep-soft);
  color: var(--sep);
  font-size: 0.72rem;
  padding: 0.05rem 0.4rem;
  border-radius: 6px;
  vertical-align: middle;
}

/* Popover grammar links (contextual lesson triggers) */
.pop-grammar {
  margin-top: 0.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}
.grammar-link {
  text-align: left;
  font-size: 0.82rem;
  background: var(--sep-soft);
  color: var(--sep);
  border: none;
  border-radius: 7px;
  padding: 0.3rem 0.5rem;
  cursor: pointer;
}
.grammar-link:hover {
  filter: brightness(0.97);
}

/* ---- Navigation ---- */
.nav {
  display: flex;
  gap: 0.5rem;
  padding: 0.75rem 2rem 0;
  max-width: 760px;
  margin: 0 auto;
}
.nav-btn {
  background: transparent;
  color: var(--muted);
  border: none;
  border-bottom: 2px solid transparent;
  border-radius: 0;
  padding: 0.4rem 0.6rem;
  font-weight: 600;
  cursor: pointer;
}
.nav-btn.on {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.muted {
  color: var(--muted);
}
.primary-btn {
  font: inherit;
  font-weight: 600;
  padding: 0.5rem 1.1rem;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 9px;
  cursor: pointer;
}
.link-btn {
  background: none;
  border: none;
  color: var(--accent);
  cursor: pointer;
  padding: 0;
  font: inherit;
}

/* ---- Review (flashcards) ---- */
.review,
.grammar {
  max-width: 760px;
  margin: 1rem auto;
  padding: 0 2rem;
}
.review-empty {
  color: var(--muted);
  text-align: center;
  margin-top: 3rem;
}
.review-count {
  color: var(--muted);
  font-size: 0.85rem;
  margin-bottom: 0.75rem;
}
.flashcard {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  box-shadow: var(--shadow);
  padding: 2rem;
  text-align: center;
  margin-bottom: 1.25rem;
}
.card-word {
  font-size: 2rem;
  font-weight: 700;
  color: var(--accent);
}
.card-cloze {
  margin-top: 0.75rem;
  font-size: 1.15rem;
  color: var(--fg);
}
.card-answer {
  margin-top: 1.25rem;
  border-top: 1px solid var(--border);
  padding-top: 1rem;
}
.card-gloss {
  font-size: 1.5rem;
}
.grade-row {
  display: flex;
  gap: 0.5rem;
}
.grade-btn {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.15rem;
  padding: 0.5rem 0;
  background: var(--surface-2);
  color: var(--fg);
  border: 1px solid var(--border);
  border-radius: 9px;
  font-weight: 600;
  cursor: pointer;
}
.grade-btn small {
  color: var(--muted);
  font-weight: 400;
}
.grade-btn:hover {
  background: var(--accent-soft);
}
.grade-btn.suggested {
  border-color: var(--accent);
  box-shadow: inset 0 0 0 1px var(--accent);
}

.stage-badge {
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 0.72rem;
  font-weight: 600;
  padding: 0.05rem 0.45rem;
  border-radius: 6px;
}
.card-prompt {
  color: var(--muted);
  font-size: 0.9rem;
}
.card-hint {
  margin-top: 0.5rem;
  font-family: ui-monospace, monospace;
  letter-spacing: 0.1em;
  color: var(--sep);
}
.produce-input {
  margin-top: 1rem;
  width: 100%;
  font: inherit;
  font-size: 1.2rem;
  text-align: center;
  padding: 0.5rem;
  background: var(--surface-2);
  color: var(--fg);
  border: 1px solid var(--border);
  border-radius: 9px;
}
.produce-feedback {
  margin-top: 0.75rem;
  min-height: 1.5rem;
  font-size: 1.05rem;
}
.fb-ok {
  color: var(--accent);
  font-weight: 600;
}
.fb-almost {
  color: var(--sep);
}
.fb-no {
  color: var(--muted);
}

/* ---- Grammar production drill (M11) ---- */
.gp-start-btn {
  display: block;
  width: 100%;
  margin-bottom: 1rem;
}
.gp-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
  color: var(--muted);
  font-size: 0.9rem;
}
.production .card-prompt {
  font-size: 1.1rem;
  line-height: 1.5;
}
.mastery-box {
  margin-bottom: 1.25rem;
}
.mastery-h {
  color: var(--accent);
  font-size: 1rem;
  margin: 0 0 0.5rem;
}
.mastery-list {
  list-style: none;
  padding: 0;
  margin: 0;
}
.mastery-row {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.2rem 0;
  font-size: 0.9rem;
}
.mastery-topic {
  flex: 0 0 11rem;
}
.mastery-bar {
  flex: 1;
  height: 8px;
  background: var(--surface-2);
  border-radius: 5px;
  overflow: hidden;
}
.mastery-fill {
  display: block;
  height: 100%;
  background: var(--accent);
  border-radius: 5px;
}
.mastery-pct {
  flex: 0 0 2.5rem;
  text-align: right;
}

/* ---- Grammar lessons ---- */
.grammar-h {
  color: var(--accent);
}
.lesson-list {
  list-style: none;
  padding: 0;
}
.lesson-item {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 11px;
  padding: 0.85rem 1rem;
  margin-bottom: 0.6rem;
  cursor: pointer;
}
.lesson-item:hover {
  border-color: var(--accent);
}
.lesson-main {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}
.lesson-title {
  font-weight: 700;
}
.lesson-level {
  font-size: 0.72rem;
  background: var(--accent-soft);
  color: var(--accent);
  padding: 0.05rem 0.45rem;
  border-radius: 6px;
}
.lesson-summary {
  margin-top: 0.25rem;
}
.lesson-met {
  font-size: 0.8rem;
  margin-top: 0.3rem;
}
.lesson-explain {
  font-size: 1.05rem;
}
.example-table {
  border-collapse: collapse;
  margin: 1rem 0;
  width: 100%;
}
.example-table td {
  padding: 0.35rem 0.6rem;
  border-bottom: 1px solid var(--border);
}
.ex-de {
  font-weight: 600;
}

/* ---- Settings ---- */
.settings {
  max-width: 760px;
  margin: 1rem auto;
  padding: 0 2rem;
}
.setting-group {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.5rem 1.1rem;
  margin-bottom: 1rem;
}
.setting-group h3 {
  color: var(--accent);
  margin: 0.6rem 0;
}
.setting-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.6rem 0;
  border-top: 1px solid var(--border);
}
.setting-group h3 + .setting-row {
  border-top: none;
}
.setting-row select,
.setting-row input[type="time"] {
  font: inherit;
  padding: 0.3rem 0.5rem;
  background: var(--surface-2);
  color: var(--fg);
  border: 1px solid var(--border);
  border-radius: 7px;
}
.setting-row input[type="checkbox"] {
  width: 1.1rem;
  height: 1.1rem;
}
.setting-row input[type="number"] {
  width: 4.5rem;
  font: inherit;
  padding: 0.3rem 0.5rem;
  background: var(--surface-2);
  color: var(--fg);
  border: 1px solid var(--border);
  border-radius: 7px;
}
.setting-note {
  font-size: 0.82rem;
  margin: 0.3rem 0 0.6rem;
}

/* ---- Nav metadata (level + streak) ---- */
.nav-spacer {
  flex: 1;
}
.nav-meta {
  align-self: center;
  font-size: 0.8rem;
  color: var(--muted);
  padding: 0 0.4rem;
}
.nav-meta.streak {
  color: var(--sep);
  font-weight: 600;
}

/* ---- Onboarding ---- */
.onboarding {
  max-width: 620px;
  margin: 2.5rem auto;
  padding: 0 2rem;
}
.ob-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  box-shadow: var(--shadow);
  padding: 2rem;
}
.ob-card h2 {
  color: var(--accent);
  margin-top: 0;
}
.ob-progress {
  color: var(--muted);
  font-size: 0.85rem;
  margin-bottom: 0.5rem;
}
.ob-level {
  color: var(--accent);
}
.ob-words {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 1.25rem 0;
}
.ob-word {
  font: inherit;
  font-size: 1.05rem;
  padding: 0.45rem 0.8rem;
  background: var(--surface-2);
  color: var(--fg);
  border: 2px solid var(--border);
  border-radius: 10px;
  cursor: pointer;
}
.ob-word.on {
  background: var(--accent-soft);
  border-color: var(--accent);
  color: var(--accent);
  font-weight: 600;
}

/* ---- Practice ---- */
.practice {
  max-width: 760px;
  margin: 1rem auto;
  padding: 0 2rem;
}
.pr-meta {
  color: var(--muted);
  font-size: 0.85rem;
  margin-bottom: 0.75rem;
}
.pr-trans {
  margin-top: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border);
  font-size: 1.05rem;
}
.pr-controls {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-top: 1.25rem;
}