:root {
  color-scheme: light;
  --bg: #f4f1ea;
  --panel: rgba(255, 255, 255, 0.88);
  --panel-strong: #ffffff;
  --line: rgba(22, 28, 36, 0.1);
  --text: #16202a;
  --muted: #6b7280;
  --accent: #1f3a5f;
  --accent-soft: #e7edf6;
  --ok: #1f7a4d;
  --warn: #8b5e34;
  --shadow: 0 18px 40px rgba(22, 28, 36, 0.08);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
  background:
    radial-gradient(circle at top, rgba(255, 255, 255, 0.65), transparent 35%),
    var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

body {
  padding: 16px;
}

[v-cloak] {
  display: none;
}

.shell {
  max-width: 960px;
  margin: 0 auto;
  padding-bottom: 90px;
}

.topbar,
.card {
  border: 1px solid var(--line);
  border-radius: 22px;
  background: var(--panel);
  backdrop-filter: blur(18px);
  box-shadow: var(--shadow);
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 20px;
  margin-bottom: 16px;
}

.eyebrow,
.section-label,
.detail-label {
  margin: 0;
  color: var(--muted);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin: 0;
}

h1 {
  margin-top: 6px;
  font-size: 26px;
}

h2 {
  font-size: 18px;
}

.content {
  display: grid;
  gap: 16px;
}

.card {
  padding: 18px;
}

.hero {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.96), rgba(231, 237, 246, 0.8));
}

.stack {
  display: grid;
  gap: 16px;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
  margin-top: 14px;
}

.stat-item {
  padding: 14px;
  border-radius: 16px;
  background: var(--panel-strong);
  border: 1px solid var(--line);
}

.stat-value {
  display: block;
  font-size: 22px;
  font-weight: 700;
}

.stat-label {
  display: block;
  margin-top: 4px;
  color: var(--muted);
  font-size: 13px;
}

.tabbar {
  display: flex;
  gap: 10px;
  padding: 10px;
}

.tab-btn,
.primary-btn,
.ghost-btn {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 10px 16px;
  font: inherit;
  cursor: pointer;
  transition: 0.2s ease;
}

.tab-btn,
.ghost-btn {
  background: rgba(255, 255, 255, 0.78);
  color: var(--text);
}

.tab-btn.active,
.primary-btn {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

button:disabled {
  opacity: 0.65;
  cursor: progress;
}

.spinner {
  display: inline-block;
  width: 14px;
  height: 14px;
  margin-right: 6px;
  border: 2px solid rgba(255, 255, 255, 0.4);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  vertical-align: middle;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

.loading-banner {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 16px;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: var(--accent-soft);
  font-size: 14px;
  color: var(--accent);
}

.loading-dots {
  display: inline-flex;
  gap: 4px;
  flex-shrink: 0;
}

.loading-dots i {
  display: block;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  animation: bounce 1.2s ease-in-out infinite;
}

.loading-dots i:nth-child(2) {
  animation-delay: 0.15s;
}

.loading-dots i:nth-child(3) {
  animation-delay: 0.3s;
}

@keyframes bounce {
  0%, 80%, 100% {
    transform: scale(0.6);
    opacity: 0.4;
  }
  40% {
    transform: scale(1);
    opacity: 1;
  }
}

.field {
  display: grid;
  gap: 8px;
}

.field span {
  color: var(--muted);
  font-size: 14px;
}

.field-hint {
  color: var(--muted);
  font-size: 12px;
  line-height: 1.5;
}

textarea {
  width: 100%;
  resize: vertical;
  min-height: 120px;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 14px 16px;
  background: rgba(255, 255, 255, 0.92);
  color: var(--text);
  font: inherit;
  outline: none;
}

textarea:focus {
  border-color: rgba(31, 58, 95, 0.3);
  box-shadow: 0 0 0 4px rgba(31, 58, 95, 0.08);
}

.actions,
.review-actions,
.row-between {
  display: flex;
  gap: 10px;
  align-items: center;
  flex-wrap: wrap;
  justify-content: space-between;
}

.actions {
  justify-content: flex-start;
}

.primary-btn,
.ghost-btn.small {
  min-height: 40px;
}

.message {
  padding: 12px 14px;
  border-radius: 14px;
  border: 1px solid var(--line);
  font-size: 14px;
}

.message.error {
  background: rgba(139, 94, 52, 0.08);
  color: var(--warn);
}

.message.success {
  background: rgba(31, 122, 77, 0.08);
  color: var(--ok);
}

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

.result-card {
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--panel-strong);
  padding: 16px;
  display: grid;
  gap: 12px;
}

.result-card.compact {
  padding: 14px;
}

.result-head {
  display: flex;
  gap: 12px;
  justify-content: space-between;
  align-items: flex-start;
}

.result-head h3 {
  font-size: 20px;
}

.result-head p {
  color: var(--muted);
  margin-top: 4px;
}

.detail-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.detail-text,
.example-list,
.meta-row {
  color: var(--text);
  line-height: 1.6;
}

.example-list {
  margin: 8px 0 0;
  padding-left: 18px;
}

.meta-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  color: var(--muted);
  font-size: 13px;
}

.status-tag {
  display: inline-flex;
  align-items: center;
  padding: 6px 10px;
  border-radius: 999px;
  font-size: 12px;
  border: 1px solid var(--line);
}

.status-tag.due {
  color: var(--warn);
  background: rgba(139, 94, 52, 0.08);
}

.status-tag.ok {
  color: var(--ok);
  background: rgba(31, 122, 77, 0.08);
}

.empty-tip {
  color: var(--muted);
  text-align: center;
  padding: 24px 0;
}

.quiz-box {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 14px;
  background: rgba(255, 255, 255, 0.6);
}

.quiz-question {
  margin: 8px 0 12px;
  font-size: 15px;
  line-height: 1.6;
}

.quiz-options {
  display: grid;
  gap: 8px;
}

.quiz-option {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.9);
  cursor: pointer;
  transition: 0.2s ease;
  text-align: left;
  font: inherit;
  color: var(--text);
}

.quiz-option:hover:not(:disabled) {
  border-color: rgba(31, 58, 95, 0.3);
  background: var(--accent-soft);
}

.quiz-option:disabled {
  cursor: default;
}

.quiz-letter {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  border: 1px solid var(--line);
  font-size: 13px;
  font-weight: 600;
  flex-shrink: 0;
}

.quiz-option.correct {
  border-color: var(--ok);
  background: rgba(31, 122, 77, 0.08);
}

.quiz-option.correct .quiz-letter {
  background: var(--ok);
  color: #fff;
  border-color: var(--ok);
}

.quiz-option.wrong {
  border-color: var(--warn);
  background: rgba(139, 94, 52, 0.08);
}

.quiz-option.wrong .quiz-letter {
  background: var(--warn);
  color: #fff;
  border-color: var(--warn);
}

.quiz-option.dim {
  opacity: 0.45;
}

.quiz-result {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
}

.quiz-answer {
  font-size: 14px;
  font-weight: 600;
  color: var(--ok);
}

.quiz-explanation {
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.6;
  color: var(--muted);
}

.cache-tag {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 11px;
  letter-spacing: 0.05em;
  color: var(--muted);
  background: rgba(107, 114, 128, 0.08);
  border: 1px solid var(--line);
}

.result-head-actions {
  display: flex;
  gap: 8px;
  align-items: center;
  flex-shrink: 0;
}

.cache-hint {
  padding: 10px 14px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: rgba(107, 114, 128, 0.05);
  font-size: 13px;
  color: var(--muted);
  line-height: 1.5;
}

.quiz-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 4px;
}

.refresh-btn {
  font-size: 13px;
  padding: 6px 12px;
  min-height: 32px;
}

.small-spinner {
  width: 10px;
  height: 10px;
  margin-right: 4px;
  border-width: 1.5px;
}

.word-actions {
  display: flex;
  justify-content: flex-end;
}

.danger-btn {
  color: var(--warn);
  border-color: rgba(139, 94, 52, 0.3);
}

.danger-btn:hover {
  background: rgba(139, 94, 52, 0.08);
}

.footer-nav {
  position: fixed;
  left: 16px;
  right: 16px;
  bottom: 16px;
  max-width: 960px;
  margin: 0 auto;
  display: flex;
  gap: 10px;
  justify-content: space-between;
}

.footer-nav .ghost-btn {
  flex: 1;
}

@media (max-width: 720px) {
  body {
    padding: 12px;
  }

  .stats-grid,
  .detail-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .topbar {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .footer-nav {
    left: 12px;
    right: 12px;
  }
}

.tab-badge {
  display: inline-block;
  margin-left: 4px;
  padding: 1px 6px;
  border-radius: 999px;
  font-size: 11px;
  font-weight: 600;
  background: rgba(31, 58, 95, 0.1);
  color: var(--accent);
}

.task-progress-display {
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.task-progress-display .stat-value {
  font-size: 28px;
  font-weight: 700;
  color: var(--accent);
}

.task-progress-display .stat-label {
  font-size: 14px;
  color: var(--muted);
}

.word-learned {
  opacity: 0.6;
  border-left: 3px solid var(--ok);
}

.primary-btn.small {
  padding: 4px 12px;
  font-size: 13px;
  min-height: 28px;
}