/**
 * Primary · 全站多终端自适应
 * 国家地理读本课件、作业、游戏、目录页通用
 */
html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  overflow-x: clip;
  min-height: 100dvh;
}

img,
video,
canvas,
iframe {
  max-width: 100%;
  height: auto;
}

/* 课件图片位：按容器缩放，避免 height:auto 把配图撑出相框 */
body:has(> .app) .polaroid,
body:has(> .app) .hero-art,
body:has(> .app) .word-col-art,
body:has(> .app) .story-col--art,
body:has(> .app) .opt-img {
  overflow: hidden;
  min-height: 0;
  max-width: 100%;
}
body:has(> .app) .art-img,
body:has(> .app) .polaroid img {
  max-width: 100%;
  max-height: 100%;
  width: auto;
  height: auto;
  object-fit: contain;
  object-position: center;
}
body:has(> .app) .opt-img .opt-thumb {
  max-width: 100%;
  width: auto;
  height: auto;
  min-height: 0;
  object-fit: contain;
  object-position: center;
}

/* 图标 SVG 只有 viewBox 时，height:auto 会按视口宽度等比撑满整屏 */
svg {
  max-width: 100%;
}

/* ── 目录 / 书籍首页 ── */
.page {
  padding-left: max(1rem, env(safe-area-inset-left));
  padding-right: max(1rem, env(safe-area-inset-right));
}

.page .grid {
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 260px), 1fr));
}

@media (max-width: 520px) {
  .hero {
    flex-direction: column;
    align-items: flex-start;
    text-align: left;
    gap: 0.85rem;
    padding: 1.1rem 1rem;
  }

  .hero-icon {
    width: 64px;
    height: 64px;
  }

  a.card {
    padding: 0.9rem;
    gap: 0.75rem;
  }

  .card-arrow,
  .card-icon {
    flex-shrink: 0;
  }

  .hw-grid {
    grid-template-columns: 1fr;
  }

  .back {
    min-height: 44px;
    display: inline-flex;
    align-items: center;
  }
}

@media (max-width: 400px) {
  .grid {
    grid-template-columns: 1fr !important;
  }

  a.card {
    min-height: auto;
  }

  .logo-row {
    flex-wrap: wrap;
    justify-content: center;
  }
}

/* ── 课件 16:9 舞台：为「← 课程 首页」留顶栏，避免盖住书名 ── */
body:has(> .app) {
  --ng-back-hub-h: 3.35rem;
  padding-top: max(var(--ng-back-hub-h), calc(env(safe-area-inset-top) + 2.75rem));
}
body:has(> .app) > .back-hub {
  position: fixed;
  top: max(8px, env(safe-area-inset-top));
  left: max(12px, env(safe-area-inset-left));
  z-index: 100002;
  max-width: calc(100vw - 24px);
  white-space: nowrap;
}
html.sclass-has-page-nav .back-hub,
html.sclass-has-page-nav a.back-hub {
  display: none !important;
}
html.sclass-has-page-nav body:has(> .app) {
  --ng-back-hub-h: 0px;
  padding-top: 0;
}
body:has(> .app) > .app {
  --ng-stage-h: calc(100dvh - max(var(--ng-back-hub-h, 3.35rem), calc(env(safe-area-inset-top) + 2.75rem)));
  width: min(100vw, calc(var(--ng-stage-h) * 16 / 9));
  height: min(var(--ng-stage-h), calc(100vw * 9 / 16));
  max-width: min(100vw, calc(var(--ng-stage-h) * 16 / 9));
  max-height: min(var(--ng-stage-h), calc(100vw * 9 / 16));
}
@media (pointer: fine) and (min-width: 821px), (min-width: 1025px) {
  body:has(> .app):has(.word-study-wrap) {
    align-items: stretch;
    justify-content: flex-start;
  }
  body:has(> .app):has(.word-study-wrap) > .app {
    width: 100%;
    max-width: none;
    height: var(--ng-stage-h);
    max-height: none;
    aspect-ratio: auto;
    margin: 0;
  }
  html.sclass-has-page-nav body:has(> .app):has(.word-study-wrap) {
    height: 100dvh;
    max-height: 100dvh;
    overflow: hidden;
  }
  html.sclass-has-page-nav body:has(> .app):has(.word-study-wrap) > .app {
    --ng-stage-h: calc(100dvh - var(--sclass-nav-h, 3.15rem) - env(safe-area-inset-top, 0px) - env(safe-area-inset-bottom, 0px));
    flex: 1 1 auto;
    min-height: 0;
    width: 100%;
    height: auto;
    max-height: none;
  }
}

/* ── 国家地理互动课件 · 手机强制纵向长页 ── */
@media (pointer: coarse) and (max-width: 1024px), (max-width: 820px) {
  html.ng-courseware-portrait,
  html:has(> body > .app) {
    height: auto !important;
    max-height: none !important;
    overflow-x: hidden !important;
    overflow-y: auto !important;
  }

  html.ng-courseware-portrait body,
  body:has(> .app) {
    display: block !important;
    padding:
      max(3.75rem, calc(env(safe-area-inset-top) + 3.25rem))
      max(4px, env(safe-area-inset-right))
      max(1.5rem, env(safe-area-inset-bottom))
      max(4px, env(safe-area-inset-left)) !important;
    align-items: stretch !important;
    justify-content: flex-start !important;
    height: auto !important;
    max-height: none !important;
    min-height: 100dvh !important;
    overflow-x: hidden !important;
    overflow-y: auto !important;
    -webkit-overflow-scrolling: touch;
    overscroll-behavior-y: auto;
  }

  html.ng-courseware-portrait body .app,
  body:has(> .app) .app {
    width: 100% !important;
    max-width: 100% !important;
    height: auto !important;
    min-height: calc(100dvh - 3.75rem) !important;
    max-height: none !important;
    aspect-ratio: auto !important;
    overflow: visible !important;
    margin: 0 !important;
    padding: 0.35rem 0.4rem 0.65rem !important;
  }

  html.ng-courseware-portrait body .book-cover,
  body:has(> .app) .book-cover {
    min-height: calc(100dvh - 4.25rem) !important;
    max-height: none !important;
    height: auto !important;
    overflow: visible !important;
  }

  html.ng-courseware-portrait body .book-inner,
  body:has(> .app) .book-inner {
    overflow: visible !important;
    flex: 1 1 auto !important;
    height: auto !important;
    max-height: none !important;
  }

  html.ng-courseware-portrait body .book-main,
  body:has(> .app) .book-main {
    overflow: visible !important;
    flex: 1 1 auto !important;
    min-height: 0 !important;
    height: auto !important;
    max-height: none !important;
  }

  html.ng-courseware-portrait body .book-top,
  body:has(> .app) .book-top {
    gap: 0.4rem 0.6rem;
  }

  html.ng-courseware-portrait body .book-top-left .book-title,
  body:has(> .app) .book-top-left .book-title {
    font-size: clamp(0.95rem, 4.2vw, 1.15rem) !important;
  }

  html.ng-courseware-portrait body .book-top-left .book-sub,
  body:has(> .app) .book-top-left .book-sub {
    font-size: clamp(0.68rem, 2.8vw, 0.78rem) !important;
  }

  html.ng-courseware-portrait body .book-top-right,
  body:has(> .app) .book-top-right {
    width: 100%;
  }

  html.ng-courseware-portrait body .book-top-right .btns,
  body:has(> .app) .book-top-right .btns {
    width: 100%;
    justify-content: stretch;
  }

  html.ng-courseware-portrait body .book-top-right .btn,
  body:has(> .app) .book-top-right .btn {
    flex: 1 1 calc(33.33% - 0.35rem);
    min-height: 44px;
    font-size: clamp(0.72rem, 2.8vw, 0.82rem);
    padding-left: 0.35rem;
    padding-right: 0.35rem;
    white-space: normal;
    line-height: 1.2;
  }

  @supports (zoom: 1) {
    html.ng-courseware-portrait #view-words .view-body--words,
    html.ng-courseware-portrait #view-review > .view-body,
    html.ng-courseware-portrait #view-story .view-body--story,
    body:has(> .app) #view-words .view-body--words,
    body:has(> .app) #view-review > .view-body,
    body:has(> .app) #view-story .view-body--story {
      zoom: 1 !important;
    }
  }

  @supports not (zoom: 1) {
    html.ng-courseware-portrait #view-words .view-body--words,
    html.ng-courseware-portrait #view-review > .view-body,
    html.ng-courseware-portrait #view-story .view-body--story,
    body:has(> .app) #view-words .view-body--words,
    body:has(> .app) #view-review > .view-body,
    body:has(> .app) #view-story .view-body--story {
      transform: none !important;
      width: 100% !important;
      max-width: 100% !important;
      align-self: stretch !important;
    }
  }

  html.ng-courseware-portrait .view-body,
  body:has(> .app) .view-body {
    padding-left: 0.35rem !important;
    padding-right: 0.35rem !important;
  }

  html.ng-courseware-portrait .word-study-wrap,
  body:has(> .app) .word-study-wrap {
    grid-template-columns: 1fr;
    align-items: center;
    justify-items: stretch;
    width: 100%;
    max-width: none;
  }

  html.ng-courseware-portrait .word-col-art,
  body:has(> .app) .word-col-art {
    max-width: 100%;
    flex: 0 0 auto;
    width: 100%;
  }

  html.ng-courseware-portrait .word-col-panel,
  body:has(> .app) .word-col-panel {
    max-width: 100%;
    width: 100%;
  }

  html.ng-courseware-portrait .word-col-art .art-img,
  body:has(> .app) .word-col-art .art-img {
    max-height: min(46dvh, 22rem) !important;
  }

  html.ng-courseware-portrait .view-body--story .story-sentence--xl.story-sentence-row,
  body:has(> .app) .view-body--story .story-sentence--xl.story-sentence-row {
    flex-direction: column;
  }

  html.ng-courseware-portrait .view-body--story .story-col--art,
  body:has(> .app) .view-body--story .story-col--art {
    flex: 0 0 auto;
    max-width: 100%;
  }

  html.ng-courseware-portrait .opt-img,
  body:has(> .app) .opt-img {
    flex: 1 1 100%;
    max-width: 100%;
  }

  html.ng-courseware-portrait .match-cols,
  body:has(> .app) .match-cols {
    grid-template-columns: 1fr !important;
  }

  html.ng-courseware-portrait .jumble .chip,
  body:has(> .app) .jumble .chip {
    font-size: clamp(1rem, 4vw, 1.35rem);
    min-width: 2.75rem;
    min-height: 3rem;
  }

  html.ng-courseware-portrait .view,
  html.ng-courseware-portrait .view.on,
  html.ng-courseware-portrait #view-story,
  html.ng-courseware-portrait .view-body--story,
  html.ng-courseware-portrait .story-slide,
  html.ng-courseware-portrait .story-sentence--xl,
  html.ng-courseware-portrait .story-sentence--xl.story-sentence--pyramid,
  body:has(> .app) .view,
  body:has(> .app) .view.on,
  body:has(> .app) #view-story,
  body:has(> .app) .view-body--story,
  body:has(> .app) .story-slide,
  body:has(> .app) .story-sentence--xl,
  body:has(> .app) .story-sentence--xl.story-sentence--pyramid {
    height: auto !important;
    max-height: none !important;
    overflow: visible !important;
    flex: 0 0 auto !important;
  }

  html.ng-courseware-portrait .view-body--story,
  body:has(> .app) .view-body--story {
    padding-bottom: 2.25rem !important;
  }

  html.ng-courseware-portrait .story-pyramid,
  body:has(> .app) .story-pyramid {
    flex: 0 0 auto !important;
    min-height: auto !important;
    justify-content: flex-start !important;
    overflow: visible !important;
  }

  html.ng-courseware-portrait .story-zh-hold,
  body:has(> .app) .story-zh-hold {
    flex-shrink: 0 !important;
    margin-bottom: 0.35rem !important;
  }

  html.ng-courseware-portrait .view-body--story .story-sentence--pyramid .story-col--text,
  body:has(> .app) .view-body--story .story-sentence--pyramid .story-col--text {
    max-height: none !important;
    overflow: visible !important;
    flex: 0 0 auto !important;
  }

  /* 学单词：手机纵向长页，禁止 flex 压缩 + overflow 裁切 */
  html.ng-courseware-portrait #view-words,
  html.ng-courseware-portrait #view-words.view.on,
  html.ng-courseware-portrait #view-words .view-body,
  html.ng-courseware-portrait #view-words .view-body--words,
  body:has(> .app) #view-words,
  body:has(> .app) #view-words.view.on,
  body:has(> .app) #view-words .view-body,
  body:has(> .app) #view-words .view-body--words {
    flex: 0 0 auto !important;
    min-height: auto !important;
    height: auto !important;
    max-height: none !important;
    overflow: visible !important;
  }

  html.ng-courseware-portrait .word-study-wrap,
  html.ng-courseware-portrait .word-col-art,
  html.ng-courseware-portrait .word-col-art .hero-art,
  html.ng-courseware-portrait .word-col-art .polaroid,
  html.ng-courseware-portrait .word-col-panel,
  body:has(> .app) .word-study-wrap,
  body:has(> .app) .word-col-art,
  body:has(> .app) .word-col-art .hero-art,
  body:has(> .app) .word-col-art .polaroid,
  body:has(> .app) .word-col-panel {
    flex: 0 0 auto !important;
    min-height: auto !important;
    height: auto !important;
    max-height: none !important;
    overflow: visible !important;
  }
}

/* ── 作业 / 听写 / A4 预览 ── */
.page-viewport {
  width: min(210mm, calc(100vw - 24px));
  max-width: 100%;
}

@media screen and (max-width: 720px) {
  .toolbar {
    flex-direction: column;
    align-items: stretch;
    gap: 0.65rem;
  }

  .toolbar-left {
    justify-content: center;
    text-align: center;
  }

  .btn-print,
  .toolbar .btn,
  .toolbar button {
    width: 100%;
    min-height: 44px;
  }

  .page-viewport {
    width: calc(100vw - 16px);
    margin: 12px auto;
  }

  #app {
    width: 100%;
    max-width: 100%;
    padding-left: max(6px, env(safe-area-inset-left));
    padding-right: max(6px, env(safe-area-inset-right));
  }
}

/* ── 复习游戏 / 通用工具栏 ── */
.stage,
.toolbar,
.back-hub {
  max-width: min(52rem, 100%);
}

@media screen and (max-width: 640px) {
  .toolbar {
    padding-left: max(0.65rem, env(safe-area-inset-left));
    padding-right: max(0.65rem, env(safe-area-inset-right));
  }

  .toolbar .btns {
    width: 100%;
    justify-content: stretch;
  }

  .toolbar .btn {
    flex: 1 1 auto;
    min-height: 44px;
  }

  .board {
    grid-template-columns: repeat(2, 1fr) !important;
  }
}

@media screen and (max-width: 380px) {
  .board {
    grid-template-columns: 1fr 1fr !important;
    gap: 0.35rem;
  }
}

/* ── 触控与动效 ── */
@media (hover: none) and (pointer: coarse) {
  a:hover,
  button:hover,
  .btn:hover {
    transform: none;
  }

  a,
  button,
  .btn,
  .card,
  .hw,
  .back-hub {
    touch-action: manipulation;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ── 分级阅读 Level 切换 ── */
.level-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.55rem;
  margin: 1.35rem auto 0;
  max-width: 48rem;
}

.level-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  min-height: 40px;
  padding: 0.4rem 0.95rem;
  border-radius: 999px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  background: rgba(255, 255, 255, 0.05);
  color: #c5cdd8;
  text-decoration: none;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  transition: background 0.25s, border-color 0.25s, color 0.25s, transform 0.25s;
}

.level-pill:hover {
  border-color: rgba(245, 196, 0, 0.45);
  color: #fff;
  transform: translateY(-1px);
}

.level-pill.is-active {
  background: rgba(245, 196, 0, 0.18);
  border-color: rgba(245, 196, 0, 0.55);
  color: #f5c400;
}

.level-pill small {
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0;
  opacity: 0.78;
}

@media print {
  body:has(> .app) .app {
    width: auto !important;
    height: auto !important;
    max-height: none !important;
    padding: 0 !important;
  }

  .page-viewport {
    width: auto !important;
    height: auto !important;
    overflow: visible !important;
  }

  .page-viewport .page,
  .page-viewport .coloring-sheet {
    transform: none !important;
  }
}