:root {
  color-scheme: light;
  --bg: #f6f3ee;
  --ink: #202124;
  --muted: #62656a;
  --line: #d8d2c8;
  --panel: #fffdf8;
  --accent: #0f766e;
  --accent-strong: #115e59;
  --accent-soft: #d8f3ee;
  --warn: #b45309;
  --bad: #b91c1c;
  --good: #166534;
  --blue: #1d4ed8;
  --shadow: 0 12px 30px rgba(54, 45, 33, 0.08);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
}

button,
input,
select {
  font: inherit;
}

button {
  border: 1px solid var(--line);
  background: #ffffff;
  color: var(--ink);
  border-radius: 8px;
  padding: 9px 12px;
  cursor: pointer;
}

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

button.active,
button.primary {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

button.danger {
  color: var(--bad);
  border-color: #f0b9b9;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.55;
}

.topbar {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 20px;
  padding: 22px 28px 18px;
  border-bottom: 1px solid var(--line);
  background: #fffaf1;
  position: sticky;
  top: 0;
  z-index: 10;
}

h1,
h2,
h3 {
  margin: 0;
  letter-spacing: 0;
}

h1 {
  font-size: clamp(26px, 3vw, 42px);
  line-height: 1;
}

h2 {
  font-size: 15px;
  color: var(--muted);
  text-transform: uppercase;
}

h3 {
  font-size: 20px;
}

p {
  margin: 0;
}

.topbar p {
  margin-top: 8px;
  color: var(--muted);
}

.source-tabs,
.mode-tabs,
.actions,
.answer-actions,
.quiz-options,
.chips {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.source-tabs button {
  min-width: 120px;
}

.layout {
  display: grid;
  grid-template-columns: 290px minmax(0, 1fr);
  gap: 22px;
  padding: 22px 28px 40px;
}

.sidebar {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.panel,
.study-card,
.focus-item,
.progress-row {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.panel {
  padding: 16px;
}

.panel h2 {
  margin-bottom: 12px;
}

label {
  display: grid;
  gap: 6px;
  margin-bottom: 12px;
  color: var(--muted);
  font-size: 14px;
}

select,
input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 10px 11px;
  background: #fff;
  color: var(--ink);
}

.checkbox-row {
  display: flex;
  align-items: center;
  gap: 8px;
}

.checkbox-row input {
  width: auto;
}

.metrics {
  display: grid;
  gap: 11px;
}

.metrics div {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
}

.metrics strong {
  font-size: 26px;
  color: var(--accent-strong);
}

.metrics span {
  color: var(--muted);
}

.workspace {
  min-width: 0;
}

.view {
  display: none;
}

.view.active {
  display: block;
}

.toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 14px;
}

.toolbar .hint {
  color: var(--muted);
}

.study-card {
  min-height: 360px;
  padding: clamp(18px, 3vw, 34px);
}

.card-meta,
.small-meta {
  color: var(--muted);
  font-size: 13px;
  margin-bottom: 18px;
}

.card-question {
  font-size: clamp(22px, 3vw, 34px);
  line-height: 1.22;
  font-weight: 750;
  margin-bottom: 24px;
}

.card-answer {
  border-top: 1px solid var(--line);
  padding-top: 22px;
  font-size: 18px;
  line-height: 1.55;
}

.card-answer.hidden {
  display: none;
}

.rich img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 14px 0;
  border-radius: 6px;
}

.rich ul,
.rich ol {
  padding-left: 22px;
}

.rich li {
  margin: 5px 0;
}

.learn-list {
  display: grid;
  gap: 12px;
}

.learn-list .study-card {
  min-height: 0;
}

.learn-list .card-question {
  font-size: 21px;
}

.answer-actions {
  margin-top: 16px;
}

.status-pill,
.chip {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 4px 10px;
  font-size: 13px;
  color: var(--muted);
  background: white;
}

.status-pill.good {
  color: var(--good);
  border-color: #b7ddb9;
}

.status-pill.bad {
  color: var(--bad);
  border-color: #efb9b9;
}

.quiz-options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  margin-top: 18px;
}

.quiz-options button {
  text-align: left;
  min-height: 76px;
}

.quiz-options button.correct {
  border-color: var(--good);
  background: #e8f6ea;
}

.quiz-options button.wrong {
  border-color: var(--bad);
  background: #fdecec;
}

.result {
  margin-top: 14px;
  color: var(--muted);
}

.focus-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.focus-item,
.progress-row {
  padding: 16px;
}

.focus-item h3 {
  margin-bottom: 10px;
}

.focus-item ul {
  margin: 10px 0 0;
  padding-left: 18px;
}

.recommended {
  margin-top: 16px;
}

.recommended .progress-row {
  margin-bottom: 10px;
}

.progress-list {
  display: grid;
  gap: 10px;
}

.progress-row {
  display: grid;
  gap: 8px;
}

.progress-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 14px;
}

.file-button {
  display: inline-flex;
  width: auto;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 9px 12px;
  margin: 0;
  color: var(--ink);
  background: #fff;
  cursor: pointer;
}

.sync-panel .actions {
  margin-bottom: 10px;
}

.sync-status {
  color: var(--muted);
  font-size: 13px;
  line-height: 1.35;
}

.empty {
  padding: 28px;
  border: 1px dashed var(--line);
  border-radius: 8px;
  color: var(--muted);
  background: rgba(255, 255, 255, 0.5);
}

@media (max-width: 900px) {
  .topbar {
    align-items: stretch;
    flex-direction: column;
  }

  .layout {
    grid-template-columns: 1fr;
    padding: 16px;
  }

  .sidebar {
    position: static;
  }

  .quiz-options,
  .focus-grid {
    grid-template-columns: 1fr;
  }

  .toolbar {
    align-items: stretch;
    flex-direction: column;
  }
}