/* 分层学习页样式 —— 布局参考 ns-app 03-anchor-detail.png */

.learn-layout {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 16px;
  align-items: start;
  padding-bottom: 8px;
}
.learn-layout > * { min-width: 0; }

/* ---------- 左：锚点列表 ---------- */
.anchor-panel { padding: 14px; position: sticky; top: 74px; }
.anchor-panel .ap-head {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 2px 4px 12px;
}
.anchor-panel .ap-head h2 { font-size: 15px; color: var(--ink); }
.anchor-panel .ap-count {
  font-size: 11px;
  color: var(--accent);
  background: var(--accent-soft);
  border-radius: 999px;
  padding: 1px 8px;
  font-weight: 600;
}
.anchor-list { display: flex; flex-direction: column; gap: 8px; }
.anchor-item {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 11px 13px 10px;
  cursor: pointer;
  transition: all .16s ease;
  background: #fff;
}
.anchor-item:hover { border-color: #c9d4ea; box-shadow: var(--shadow); }
.anchor-item.active { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(59, 109, 240, .12); }
.anchor-item .ai-top {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 3px;
}
.anchor-item .ai-word {
  font-family: var(--serif);
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
  white-space: nowrap;
}
.anchor-item .ai-py { font-size: 11.5px; color: var(--faint); }
.anchor-item .ai-id {
  margin-left: auto;
  font-size: 10.5px;
  color: var(--faint);
  font-family: ui-monospace, Menlo, monospace;
}
.anchor-item .ai-brief {
  font-size: 12.5px;
  color: var(--muted);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ---------- 右：锚点详情 ---------- */
.detail-head {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}
.detail-head .crumb { flex: 1; }

.detail-card { padding: 22px 24px; }
.detail-title-row {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex-wrap: wrap;
}
.detail-title-row h1 {
  font-family: var(--serif);
  font-size: 30px;
  color: var(--ink);
  letter-spacing: .04em;
}
.detail-title-row .dt-py { color: var(--accent); font-weight: 600; font-size: 15px; }
.detail-meta {
  margin-top: 8px;
  font-size: 12.5px;
  color: var(--faint);
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

/* L0-L4 分层选择 */
.level-tabs {
  display: flex;
  gap: 6px;
  margin-top: 18px;
  flex-wrap: wrap;
}
.level-tab {
  border: 1px solid var(--line);
  background: #f7f9fd;
  color: var(--muted);
  font-size: 12.5px;
  font-weight: 600;
  padding: 6px 14px;
  border-radius: 999px;
  cursor: pointer;
  transition: all .16s ease;
  font-family: var(--sans);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.level-tab .lv-id {
  font-size: 11px;
  opacity: .75;
  font-family: ui-monospace, Menlo, monospace;
}
.level-tab:hover { border-color: #c9d4ea; color: var(--ink); }
.level-tab.active[data-level="L0"] { background: var(--accent-soft); border-color: var(--accent); color: var(--accent); }
.level-tab.active[data-level="L1"] { background: var(--green-soft); border-color: var(--green); color: var(--green); }
.level-tab.active[data-level="L2"] { background: var(--violet-soft); border-color: var(--violet); color: var(--violet); }
.level-tab.active[data-level="L3"] { background: var(--amber-soft); border-color: var(--amber); color: var(--amber); }
.level-tab.active[data-level="L4"] { background: #eef1f7; border-color: #94a3b8; color: #475569; }

.level-body {
  margin-top: 14px;
  background: #f8f9fc;
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: 0 12px 12px 0;
  padding: 16px 18px;
  min-height: 110px;
}
.level-body .lb-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.level-body .lb-py {
  font-family: var(--serif);
  font-size: 19px;
  color: var(--accent);
  font-weight: 700;
  letter-spacing: .06em;
  margin-bottom: 4px;
}
.level-body .lb-text { font-size: 14px; color: var(--ink-2); line-height: 1.9; }

/* ---------- 附着卡片（attachments） ---------- */
.attach-head {
  margin: 22px 0 12px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.attach-head h2 {
  font-size: 14px;
  color: var(--ink);
  letter-spacing: .04em;
}
.attach-head .att-count {
  font-size: 11px;
  color: var(--muted);
  background: #eef1f7;
  border-radius: 999px;
  padding: 1px 8px;
}
.attach-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}
.attach-card {
  padding: 16px 16px 14px;
  border-top: 3px solid transparent;
}
.attach-card.a-context { border-top-color: var(--accent); }
.attach-card.a-story   { border-top-color: var(--green); }
.attach-card.a-syntax  { border-top-color: var(--violet); }
.attach-card .at-head {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
}
.attach-card .at-head .at-name { font-size: 13.5px; font-weight: 700; color: var(--ink); }
.attach-card .at-head .tag { margin-left: auto; }
.attach-card p { font-size: 13px; color: var(--muted); line-height: 1.8; }
.attach-card .at-quote {
  font-family: var(--serif);
  color: var(--ink-2);
  display: block;
  margin-bottom: 6px;
  font-size: 13.5px;
}

/* 全句总览条 */
.sentence-strip {
  margin-top: 16px;
  padding: 16px 20px;
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}
.sentence-strip .ss-text {
  font-family: var(--serif);
  font-size: clamp(16px, 3vw, 20px);
  color: var(--ink);
  letter-spacing: .05em;
}
.sentence-strip .ss-text b { color: var(--accent); font-weight: 700; }
.sentence-strip .ss-go { margin-left: auto; }

@media (max-width: 960px) {
  .attach-grid { grid-template-columns: 1fr; }
}
@media (max-width: 860px) {
  .learn-layout { grid-template-columns: 1fr; }
  .anchor-panel { position: static; }
  .anchor-list {
    flex-direction: row;
    overflow-x: auto;
    padding-bottom: 6px;
  }
  .anchor-item { min-width: 170px; flex-shrink: 0; }
  .anchor-item .ai-brief { white-space: normal; }
  .level-tab { font-size: 12px; padding: 5px 11px; }
  .detail-card { padding: 18px 16px; }
}