/* 篇章列表的 H5 展示层，六套配色共用同一组主题变量。 */
:root .chapter-overview {
  --chapter-success: var(--theme-success);
  --chapter-success-rgb: var(--theme-success-rgb);
  --chapter-shadow: 0 16px 40px rgba(25, 48, 65, .06);
  top: calc(var(--safe-top) + 62px);
  max-width: 1180px;
  margin: 0 auto;
  padding: 20px 0;
  grid-template-columns: minmax(0, .88fr) minmax(0, 1.12fr);
  align-items: center;
  gap: clamp(18px, 3vw, 40px);
  color: var(--theme-text);
}

:root .chapter-overview > section {
  min-width: 0;
  min-height: 0;
  height: 100%;
  max-height: 548px;
  border: 1px solid var(--theme-line);
  border-radius: 24px;
  box-shadow: var(--chapter-shadow);
}

.chapter-intro {
  position: relative;
  display: flex;
  overflow: hidden;
  overflow: clip;
  flex-direction: column;
  justify-content: center;
  padding: clamp(24px, 3vw, 42px);
  background: radial-gradient(ellipse at 100% 0, rgba(var(--theme-surface-rgb), .8), transparent 65%), linear-gradient(145deg, var(--theme-soft), var(--theme-canvas));
}
.chapter-intro > :not(.chapter-watermark) { position: relative; z-index: 1; }
.chapter-eyebrow { display: flex; align-items: center; gap: 10px; color: var(--theme-primary); font-size: 11px; font-weight: 600; letter-spacing: 1px; }
.chapter-number { display: grid; place-items: center; width: 32px; height: 32px; border: 1px solid rgba(var(--theme-primary-rgb), .25); border-radius: 10px; background: rgba(var(--theme-surface-rgb), .5); font-family: "DIN Alternate", sans-serif; font-size: 14px; letter-spacing: 0; }
.chapter-title { margin: 0 0 16px; color: var(--theme-text); font-size: clamp(28px, 3.2vw, 42px); font-weight: 800; line-height: 1.25; letter-spacing: 2px; }
.chapter-description { margin: 0; color: var(--theme-secondary); font-size: 17px; font-weight: 400; line-height: 1.8; }
.chapter-description > span { display: block; }
.chapter-intro-meta { display: flex; flex-wrap: wrap; align-items: baseline; gap: 6px; margin-top: 28px; color: var(--theme-secondary); font-size: 11px; }
.chapter-intro-meta strong { color: var(--theme-primary); font-size: 23px; font-weight: 700; line-height: 1; }
.chapter-focus { flex-basis: 100%; margin-top: 4px; color: var(--theme-muted); font-size: 11px; }
:root .chapter-overview .chapter-start {
  width: min(250px, 100%);
  min-height: 44px;
  margin: 24px 0 0;
  padding: 10px 16px;
  border: 0;
  border-radius: 11px;
  background: linear-gradient(115deg, var(--theme-primary), var(--theme-primary-hover));
  color: var(--theme-on-primary);
  box-shadow: 0 5px 14px rgba(var(--theme-primary-rgb), .16);
  font-size: 13px;
  font-weight: 600;
}
.chapter-start svg { width: 18px; height: 18px; flex-shrink: 0; margin-left: 8px; }
.chapter-watermark { position: absolute; right: 8px; bottom: -10px; color: rgba(var(--theme-primary-rgb), .055); font-family: "Arial", sans-serif; font-size: 180px; font-weight: 800; line-height: 1; letter-spacing: -12px; pointer-events: none; user-select: none; }

.chapter-route { display: flex; flex-direction: column; padding: 24px; background: rgba(var(--theme-surface-rgb), .82); }
.chapter-route-header { display: flex; flex-shrink: 0; align-items: center; justify-content: space-between; gap: 12px; }
.chapter-route-eyebrow { color: var(--theme-muted); font-size: 10px; font-weight: 500; letter-spacing: 1px; }
.chapter-route-header h2 { margin: 5px 0 0; font-size: 20px; font-weight: 700; line-height: 1.4; }
.chapter-count { display: flex; flex-shrink: 0; align-items: baseline; gap: 5px; color: var(--theme-muted); font-size: 12px; white-space: nowrap; }
.chapter-count strong { color: var(--theme-primary); font-family: "DIN Alternate", sans-serif; font-size: 25px; font-weight: 700; }
.chapter-count-label { margin-left: 4px; font-size: 10px; }
.chapter-completion { height: 3px; min-height: 3px; margin: 16px 0 18px; overflow: hidden; border-radius: 3px; background: rgba(var(--theme-primary-rgb), .1); }
.chapter-completion > span { display: block; height: 100%; border-radius: inherit; background: var(--theme-primary); }
.chapter-levels { display: flex; flex: 1; flex-direction: column; gap: 10px; min-height: 0; overflow-x: hidden; overflow-y: auto; overscroll-behavior: contain; scrollbar-width: thin; scrollbar-color: var(--theme-line) transparent; touch-action: pan-y; -webkit-overflow-scrolling: touch; }
.chapter-level {
  position: relative;
  display: grid;
  flex: 1 0 54px;
  grid-template-columns: 40px minmax(0, 1fr) auto 12px;
  align-items: center;
  gap: 12px;
  min-width: 0;
  min-height: 54px;
  margin: 0;
  padding: 10px 12px;
  border: 1px solid var(--theme-line);
  border-radius: 12px;
  background: var(--theme-canvas);
  color: var(--theme-text);
  text-align: left;
  font-family: inherit;
  line-height: 1.4;
}
.chapter-level-index { display: grid; place-items: center; width: 40px; height: 40px; border-radius: 11px; background: var(--theme-soft); color: var(--theme-muted); font-family: "DIN Alternate", sans-serif; font-size: 15px; font-weight: 700; }
.chapter-level-copy { display: flex; min-width: 0; flex-direction: column; gap: 4px; }
.chapter-level-title { display: block; overflow: hidden; color: var(--theme-text); font-size: 15px; font-weight: 650; line-height: 20px; text-overflow: ellipsis; white-space: nowrap; }
.chapter-level-status { display: inline-flex; align-items: center; justify-content: center; gap: 4px; padding: 5px 8px; border-radius: 20px; background: rgba(var(--theme-primary-rgb), .06); color: var(--theme-muted); font-size: 10px; font-weight: 500; line-height: 14px; white-space: nowrap; }
.chapter-level-status svg { width: 13px; height: 13px; flex-shrink: 0; }
.chapter-status-dot { width: 5px; height: 5px; border-radius: 50%; background: currentColor; }
.chapter-level-chevron { color: var(--theme-primary); font-size: 24px; font-weight: 400; line-height: 1; text-align: center; }
.chapter-level.unlocked { border-color: rgba(var(--theme-primary-rgb), .35); background: linear-gradient(105deg, rgba(var(--theme-primary-rgb), .09), rgba(var(--theme-surface-rgb), .95)); }
.chapter-level.unlocked .chapter-level-index { background: var(--theme-primary); color: var(--theme-on-primary); }
.chapter-level.unlocked .chapter-level-status { background: rgba(var(--theme-primary-rgb), .1); color: var(--theme-primary); }
.chapter-level.completed { border-color: rgba(var(--chapter-success-rgb), .23); background: linear-gradient(105deg, rgba(var(--chapter-success-rgb), .065), rgba(var(--theme-surface-rgb), .95)); }
.chapter-level.completed .chapter-level-index, .chapter-level.completed .chapter-level-status { background: rgba(var(--chapter-success-rgb), .1); color: var(--chapter-success); }
.chapter-level.completed .chapter-level-chevron { color: var(--chapter-success); }
.chapter-level.locked { background: rgba(var(--theme-canvas-rgb), .7); cursor: not-allowed; }
.chapter-level.locked .chapter-level-title { color: var(--theme-secondary); font-weight: 500; }
.chapter-level.locked .chapter-level-chevron { visibility: hidden; }
.chapter-level.unlocked:active { background: var(--theme-soft); }
.chapter-route-note { flex-shrink: 0; margin: 16px 0 0; color: var(--theme-muted); font-size: 10px; line-height: 15px; text-align: center; }
.chapter-level:focus-visible, .chapter-start:focus-visible { outline: 3px solid var(--theme-primary); outline-offset: -3px; }

:root[data-theme="classic"] .chapter-overview {
  --chapter-success: #8bd0ae;
  --chapter-success-rgb: 139, 208, 174;
  --chapter-shadow: 0 16px 40px rgba(0, 0, 0, .18);
}

@media (hover: hover) and (pointer: fine) {
  .chapter-level.unlocked:hover { border-color: var(--theme-primary); filter: none; }
  .chapter-level.locked:hover { filter: none; }
}

@media (max-width: 1050px) {
  :root .chapter-overview { gap: 22px; }
  .chapter-intro { padding: 26px; }
  .chapter-route { padding: 20px; }
  .chapter-description { font-size: 15px; }
  .chapter-level { grid-template-columns: 34px minmax(0, 1fr) auto 10px; gap: 9px; }
  .chapter-level-index { width: 34px; height: 34px; }
  .chapter-level-title { font-size: 14px; }
}

@media (max-height: 500px), (max-width: 900px) {
  :root .chapter-overview { top: calc(var(--safe-top) + 48px); padding: 8px 0; gap: 16px; }
  :root .chapter-overview > section { max-height: none; border-radius: 16px; }
  .chapter-intro { padding: 20px; }
  .chapter-eyebrow { gap: 7px; font-size: 9px; letter-spacing: .5px; }
  .chapter-number { width: 26px; height: 26px; border-radius: 8px; font-size: 11px; }
  .chapter-title { margin: 14px 0 10px; font-size: 28px; letter-spacing: 1px; }
  .chapter-description { font-size: 13px; line-height: 1.65; }
  .chapter-intro-meta { margin-top: 16px; font-size: 10px; }
  .chapter-intro-meta strong { font-size: 20px; }
  .chapter-focus { margin-top: 2px; font-size: 9px; }
  :root .chapter-overview .chapter-start { min-height: 37px; margin-top: 18px; padding: 8px 12px; border-radius: 9px; font-size: 12px; }
  .chapter-watermark { right: 6px; bottom: -7px; font-size: 118px; letter-spacing: -8px; }
  .chapter-route { padding: 14px; }
  .chapter-route-eyebrow { display: none; }
  .chapter-route-header h2 { margin: 0; font-size: 15px; }
  .chapter-count { font-size: 10px; }
  .chapter-count strong { font-size: 20px; }
  .chapter-count-label { margin-left: 1px; font-size: 9px; }
  .chapter-completion { margin: 9px 0 11px; }
  .chapter-levels { gap: 5px; }
  .chapter-level { flex-basis: 36px; min-height: 36px; grid-template-columns: 28px minmax(0, 1fr) auto 9px; gap: 8px; padding: 3px 8px; border-radius: 9px; }
  .chapter-level-index { width: 28px; height: 28px; border-radius: 8px; font-size: 12px; }
  .chapter-level-copy { gap: 1px; }
  .chapter-level-title { font-size: 13px; line-height: 16px; }
  .chapter-level-status { gap: 3px; padding: 4px 6px; font-size: 9px; line-height: 12px; }
  .chapter-level-status svg { width: 11px; height: 11px; }
  .chapter-level-chevron { font-size: 20px; }
  .chapter-route-note { display: none; }
}

@media (max-width: 640px), (max-height: 340px) {
  :root .chapter-overview { top: calc(var(--safe-top) + 46px); padding: 4px 0; gap: 12px; }
  .chapter-intro { padding: 16px; }
  .chapter-eyebrow { gap: 6px; font-size: 8px; letter-spacing: 0; }
  .chapter-number { width: 23px; height: 23px; border-radius: 7px; font-size: 10px; }
  .chapter-title { margin: 13px 0 9px; font-size: 24px; }
  .chapter-description { font-size: 11px; line-height: 1.7; }
  .chapter-intro-meta { display: none; }
  :root .chapter-overview .chapter-start { min-height: 34px; margin-top: 18px; padding: 7px 10px; font-size: 11px; }
  .chapter-watermark { font-size: 92px; letter-spacing: -6px; }
  .chapter-route { padding: 8px; }
  .chapter-route-header { min-height: 22px; margin-bottom: 6px; gap: 5px; }
  .chapter-route-header h2 { font-size: 13px; }
  .chapter-count { gap: 3px; font-size: 9px; }
  .chapter-count strong { font-size: 17px; }
  .chapter-count-label { font-size: 8px; }
  .chapter-completion { display: none; }
  .chapter-levels { gap: 4px; }
  .chapter-level { flex-basis: 30px; min-height: 30px; grid-template-columns: 22px minmax(0, 1fr) auto; gap: 6px; padding: 3px 6px; border-radius: 8px; }
  .chapter-level-index { width: 22px; height: 22px; border-radius: 6px; font-size: 10px; }
  .chapter-level-title { font-size: 11px; line-height: 15px; }
  .chapter-level-chevron { display: none; }
  .chapter-level-status { padding: 3px 4px; font-size: 8px; gap: 2px; }
  .chapter-level-status svg { width: 10px; height: 10px; }
  .chapter-status-dot { width: 4px; height: 4px; }
}