:root {
  --eb-blue: #4168e6;
  --eb-blue-soft: #eef5ff;
  --eb-green: #45c779;
  --eb-text: #1f2a44;
  --eb-soft: #586680;
  --eb-card: rgba(255,255,255,.92);
  --eb-line: rgba(214,232,252,.96);
  --eb-radius: 24px;
  --eb-radius-lg: 34px;
  --eb-shadow: 0 24px 60px rgba(49,120,210,.14);
}

.eb-hidden {
  display: none !important;
}

.eb-section {
  margin-top: 26px;
}

/* ===== 类型 tab ===== */
.eb-type-tabs {
  display: flex;
  gap: 12px;
  margin-bottom: 20px;
}

.eb-type-tab {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 22px;
  border: 2px solid var(--eb-line);
  border-radius: 16px;
  background: linear-gradient(135deg, #fff, #f7fbff);
  color: var(--eb-soft);
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  transition: all .2s;
}

.eb-type-tab.active {
  border-color: var(--eb-blue);
  background: linear-gradient(135deg, var(--eb-blue), #6e88ff);
  color: #fff;
  box-shadow: 0 6px 20px rgba(65,104,230,.25);
}

.eb-type-icon {
  font-size: 1.3em;
}

/* ===== 主布局 ===== */
.eb-layout {
  display: grid;
  grid-template-columns: 130px minmax(0, 1fr);
  gap: 24px;
  align-items: flex-start;
  min-height: 480px;
  padding: 30px;
  border-radius: var(--eb-radius-lg);
  background:
    radial-gradient(circle at 10% 10%, rgba(255,255,255,.96), transparent 28%),
    radial-gradient(circle at 92% 8%, rgba(255,232,146,.24), transparent 24%),
    linear-gradient(135deg, rgba(255,255,255,.94), rgba(238,247,255,.90));
  border: 1px solid rgba(255,255,255,.86);
  box-shadow: var(--eb-shadow);
}

/* ===== 左侧级别 ===== */
.eb-levels {
  position: sticky;
  top: 114px;
  display: grid;
  gap: 10px;
  padding: 14px;
  border-radius: 26px;
  background: rgba(255,255,255,.70);
  border: 1px solid rgba(255,255,255,.88);
  box-shadow: 0 16px 34px rgba(70,122,195,.10);
}

.eb-level-btn {
  min-height: 50px;
  padding: 0 10px;
  border: 2px solid rgba(218,234,255,.96);
  border-radius: 18px;
  background: linear-gradient(135deg, #fff, #f7fbff);
  color: #36527d;
  font-size: 15px;
  font-weight: 800;
  cursor: pointer;
  transition: transform .18s, box-shadow .18s, border-color .18s, background .18s;
  text-align: center;
}

.eb-level-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(65,104,230,.15);
}

.eb-level-btn.active {
  border-color: var(--eb-blue);
  background: linear-gradient(135deg, var(--eb-blue), #6e88ff);
  color: #fff;
  box-shadow: 0 8px 22px rgba(65,104,230,.28);
}

/* ===== 三级分类栏 ===== */
.eb-thirds-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 16px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--eb-line);
}

.eb-third-btn {
  padding: 6px 16px;
  border: 1.5px solid var(--eb-line);
  border-radius: 10px;
  background: transparent;
  color: var(--eb-soft);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all .18s;
}

.eb-third-btn.active {
  border-color: var(--eb-green);
  background: var(--eb-green);
  color: #fff;
}

/* ===== 绘本网格 ===== */
.eb-book-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  gap: 14px;
}

.eb-book-card {
  border-radius: 14px;
  overflow: hidden;
  background: var(--eb-card);
  box-shadow: 0 4px 12px rgba(0,0,0,.06);
  cursor: pointer;
  transition: transform .2s, box-shadow .2s;
  position: relative;
}

.eb-book-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(0,0,0,.12);
}

.eb-book-card.active {
  outline: 3px solid var(--eb-blue);
  outline-offset: -1px;
}

.eb-book-card.disabled {
  opacity: 0.4;
  pointer-events: none;
  filter: grayscale(0.6);
}

.eb-book-cover {
  width: 100%;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  display: block;
  background: #eee;
}

.eb-book-name {
  padding: 6px 8px;
  font-size: 12px;
  font-weight: 600;
  text-align: center;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  color: var(--eb-text);
}

.eb-lock-badge {
  position: absolute;
  top: 6px;
  right: 6px;
  background: rgba(0,0,0,.5);
  color: #fff;
  font-size: 11px;
  padding: 2px 6px;
  border-radius: 4px;
}

/* ===== 朗读页 ===== */
.eb-reader-section {
  position: fixed;
  inset: 0;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  max-width: none;
  margin: 0;
  padding: 0;
  height: 100vh;
  height: 100dvh;
  background: linear-gradient(180deg, #87CEEB 0%, #b5e8f7 35%, #d4f0d4 50%, #5a9e3e 50%, #4a8c2e 100%);
  overflow: hidden;
}

.eb-reader-section::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    /* 太阳 */
    radial-gradient(circle 40px at 88% 8%, #ffe066 0%, #ffcc00 40%, transparent 60%),
    radial-gradient(circle 60px at 88% 8%, rgba(255,224,102,.25) 0%, transparent 70%),
    /* 白云 */
    radial-gradient(ellipse 70px 30px at 15% 12%, rgba(255,255,255,.85) 0%, transparent 100%),
    radial-gradient(ellipse 50px 22px at 12% 14%, rgba(255,255,255,.8) 0%, transparent 100%),
    radial-gradient(ellipse 60px 26px at 18% 11%, rgba(255,255,255,.8) 0%, transparent 100%),
    radial-gradient(ellipse 80px 32px at 45% 8%, rgba(255,255,255,.8) 0%, transparent 100%),
    radial-gradient(ellipse 55px 24px at 42% 10%, rgba(255,255,255,.75) 0%, transparent 100%),
    radial-gradient(ellipse 65px 28px at 48% 7%, rgba(255,255,255,.75) 0%, transparent 100%),
    /* 远处小山丘 */
    radial-gradient(ellipse 300px 60px at 20% 52%, #6aad45 0%, transparent 100%),
    radial-gradient(ellipse 250px 50px at 75% 51%, #5fa03a 0%, transparent 100%),
    /* 草地纹理 */
    radial-gradient(ellipse 8px 20px at 5% 95%, #3d7a1e 0%, transparent 100%),
    radial-gradient(ellipse 6px 18px at 10% 92%, #4a8c2e 0%, transparent 100%),
    radial-gradient(ellipse 7px 22px at 20% 97%, #3d7a1e 0%, transparent 100%),
    radial-gradient(ellipse 8px 16px at 30% 93%, #4a8c2e 0%, transparent 100%),
    radial-gradient(ellipse 6px 20px at 45% 96%, #3d7a1e 0%, transparent 100%),
    radial-gradient(ellipse 7px 18px at 55% 94%, #4a8c2e 0%, transparent 100%),
    radial-gradient(ellipse 8px 22px at 65% 98%, #3d7a1e 0%, transparent 100%),
    radial-gradient(ellipse 6px 16px at 75% 92%, #4a8c2e 0%, transparent 100%),
    radial-gradient(ellipse 7px 20px at 85% 95%, #3d7a1e 0%, transparent 100%),
    radial-gradient(ellipse 8px 18px at 95% 93%, #4a8c2e 0%, transparent 100%),
    /* 小花朵 */
    radial-gradient(circle 4px at 8% 88%, #ff6b8a 0%, transparent 100%),
    radial-gradient(circle 3px at 9% 87%, #ff6b8a 0%, transparent 100%),
    radial-gradient(circle 3px at 7% 87%, #ff6b8a 0%, transparent 100%),
    radial-gradient(circle 2px at 8% 87.5%, #ffeb3b 0%, transparent 100%),
    radial-gradient(circle 4px at 25% 91%, #ff9ccc 0%, transparent 100%),
    radial-gradient(circle 3px at 26% 90%, #ff9ccc 0%, transparent 100%),
    radial-gradient(circle 3px at 24% 90%, #ff9ccc 0%, transparent 100%),
    radial-gradient(circle 2px at 25% 90.5%, #ffeb3b 0%, transparent 100%),
    radial-gradient(circle 4px at 70% 89%, #fff176 0%, transparent 100%),
    radial-gradient(circle 3px at 71% 88%, #fff176 0%, transparent 100%),
    radial-gradient(circle 3px at 69% 88%, #fff176 0%, transparent 100%),
    radial-gradient(circle 2px at 70% 88.5%, #ff9800 0%, transparent 100%),
    radial-gradient(circle 4px at 90% 92%, #ce93d8 0%, transparent 100%),
    radial-gradient(circle 3px at 91% 91%, #ce93d8 0%, transparent 100%),
    radial-gradient(circle 3px at 89% 91%, #ce93d8 0%, transparent 100%),
    radial-gradient(circle 2px at 90% 91.5%, #ffeb3b 0%, transparent 100%),
    /* 小树 */
    radial-gradient(ellipse 30px 40px at 3% 78%, #2e7d32 0%, transparent 100%),
    radial-gradient(ellipse 25px 35px at 5% 76%, #388e3c 0%, transparent 100%),
    radial-gradient(ellipse 6px 20px at 4% 88%, #5d4037 0%, transparent 100%),
    radial-gradient(ellipse 35px 45px at 96% 76%, #2e7d32 0%, transparent 100%),
    radial-gradient(ellipse 28px 38px at 98% 74%, #388e3c 0%, transparent 100%),
    radial-gradient(ellipse 6px 20px at 97% 86%, #5d4037 0%, transparent 100%);
}

.eb-reader-section > * {
  position: relative;
  z-index: 1;
}

.eb-reader-toolbar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: rgba(255,255,255,.75);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(0,0,0,.06);
  flex-shrink: 0;
}

.eb-back-btn {
  background: none;
  border: none;
  color: var(--eb-blue);
  font-size: 18px;
  font-weight: 700;
  cursor: pointer;
  padding: 4px 8px;
  line-height: 1;
}

.eb-reader-title {
  font-weight: 700;
  font-size: 14px;
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  color: var(--eb-text);
}

.eb-page-indicator {
  font-size: 12px;
  color: #888;
  white-space: nowrap;
}

.eb-tool-btn {
  width: 32px;
  height: 32px;
  border: 1.5px solid rgba(0,0,0,.1);
  border-radius: 8px;
  background: rgba(255,255,255,.5);
  color: var(--eb-blue);
  font-size: 18px;
  font-weight: 700;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all .18s;
  flex-shrink: 0;
  line-height: 1;
}

.eb-tool-btn:hover:not(:disabled) {
  background: rgba(255,255,255,.8);
}

.eb-tool-btn:disabled {
  opacity: 0.25;
  cursor: not-allowed;
}

.eb-mode-switch {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 12px;
  cursor: pointer;
  white-space: nowrap;
  color: var(--eb-soft);
  flex-shrink: 0;
}

.eb-reader-stage {
  display: flex;
  justify-content: center;
  align-items: center;
  flex: 1;
  min-height: 0;
  padding: 12px;
  cursor: pointer;
  overflow: hidden;
  position: relative;
  -webkit-user-select: none;
  user-select: none;
  -webkit-touch-callout: none;
}

.eb-reader-stage::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 2;
}

.eb-page-image {
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  display: block;
  border-radius: 8px;
  box-shadow: 0 8px 30px rgba(0,0,0,.12);
  pointer-events: none;
  -webkit-user-drag: none;
  user-drag: none;
}

/* ===== 响应式 ===== */
@media (max-width: 640px) {
  .eb-type-tabs {
    flex-direction: column;
    gap: 8px;
  }

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

  .eb-levels {
    position: static;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    padding: 10px;
  }

  .eb-level-btn {
    min-height: 40px;
    padding: 0 14px;
    font-size: 13px;
  }

  .eb-book-grid {
    grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
    gap: 10px;
  }

  .eb-reader-stage {
    padding: 8px;
  }
}