.pdf-container {
  max-width: 1000px;
  margin: 0 auto;
  padding: 20px;
}

.pdf-card {
  background: #fff;
  border-radius: 12px;
  padding: 24px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
}

.pdf-title {
  font-size: 22px;
  font-weight: 700;
  color: #222;
  margin: 0 0 16px 0;
  line-height: 1.4;
}

.pdf-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  margin-bottom: 16px;
  padding-bottom: 16px;
  border-bottom: 1px solid #f0f0f0;
}

.pdf-meta .meta-item {
  font-size: 14px;
  color: #555;
  line-height: 1.8;
}

.pdf-meta .meta-item label {
  color: #999;
  margin-right: 4px;
}

.pdf-meta .meta-item label::after {
  content: '：';
}

/* PDF封面+下载区域 */
.pdf-download-section {
  display: flex;
  gap: 24px;
  margin-bottom: 24px;
  padding-bottom: 24px;
  border-bottom: 1px solid #f0f0f0;
}

.pdf-cover {
  width: 380px;
  flex-shrink: 0;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  background: #f5f5f5;
}

.pdf-cover img {
  width: 110%;
  display: block;
}

.pdf-download-info {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 12px;
}

.pdf-file-info {
  background: #f8f9fa;
  border-radius: 8px;
  padding: 14px 16px;
}

.file-info-row {
  font-size: 14px;
  color: #555;
  line-height: 2;
  display: flex;
}

.info-label {
  color: #999;
  width: 70px;
  flex-shrink: 0;
}

.info-value {
  color: #333;
}

.pdf-download-btn {
  display: inline-block;
  padding: 14px 32px;
  background: linear-gradient(135deg, #409eff, #337ecc);
  color: #fff;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  text-align: center;
  transition: all 0.3s;
  box-shadow: 0 4px 12px rgba(64,158,255,0.3);
}

.pdf-download-btn:hover {
  background: linear-gradient(135deg, #337ecc, #2d6bb5);
  box-shadow: 0 6px 16px rgba(64,158,255,0.4);
  transform: translateY(-1px);
  color: #fff;
}

.download-tip {
  font-size: 12px;
  color: #bbb;
  margin: 0;
  text-align: center;
}

/* 内容介绍 */
.pdf-intro {
  margin-bottom: 24px;
  padding-bottom: 24px;
  border-bottom: 1px solid #f0f0f0;
}

.intro-body p {
  font-size: 14px;
  color: #555;
  line-height: 1.8;
  margin: 0 0 12px 0;
}

.intro-body p:last-child {
  margin-bottom: 0;
}

/* 目录 */
.pdf-toc {
  margin-bottom: 24px;
  padding-bottom: 24px;
  border-bottom: 1px solid #f0f0f0;
}

.toc-body {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.toc-part h4 {
  font-size: 14px;
  font-weight: 600;
  color: #409eff;
  margin: 0 0 10px 0;
  padding-left: 10px;
  border-left: 3px solid #409eff;
}

.toc-part ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.toc-part li {
  font-size: 13px;
  color: #666;
  line-height: 2;
  padding-left: 10px;
  position: relative;
}

.toc-part li::before {
  content: '•';
  color: #409eff;
  position: absolute;
  left: -2px;
}

/* 图片展示 - 纵向滚动 */
.pdf-gallery {
  margin-bottom: 24px;
  padding-bottom: 24px;
  border-bottom: 1px solid #f0f0f0;
}

.gallery-list {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}

.gallery-item {
  width: 100%;
  max-width: 800px;
  border-radius: 8px;
  overflow: hidden;
  background: #f5f5f5;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.gallery-item img {
  width: 100%;
  height: auto;
  display: block;
}

.gallery-item .page-label {
  text-align: center;
  padding: 8px;
  font-size: 13px;
  color: #999;
  background: #fafafa;
  border-top: 1px solid #f0f0f0;
}

/* ===== 上下篇导航 ===== */
.pdf-nav {
  display: flex;
  justify-content: space-between;
  align-items: stretch;
  margin-top: 20px;
  gap: 16px;
}

.pdf-nav a {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 16px 20px;
  background: #fff;
  border: 1px solid #e8e8e8;
  border-radius: 10px;
  font-size: 14px;
  color: #555;
  text-decoration: none;
  transition: all 0.25s;
  min-width: 0;
}

.pdf-nav a:hover {
  border-color: #409eff;
  background: #f8fbff;
  box-shadow: 0 2px 12px rgba(64,158,255,0.1);
}

.pdf-nav .nav-prev {
  text-align: left;
}

.pdf-nav .nav-next {
  text-align: right;
}

.pdf-nav .nav-label {
  font-size: 12px;
  color: #bbb;
  margin-bottom: 4px;
}

.pdf-nav .nav-title {
  font-size: 14px;
  color: #333;
  font-weight: 500;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.pdf-nav a:hover .nav-title {
  color: #409eff;
}

.pdf-nav .nav-disabled {
  opacity: 0.4;
  cursor: default;
  pointer-events: none;
}

/* 响应式 */
@media (max-width: 768px) {
  .pdf-container {
    padding: 12px;
  }

  .pdf-card {
    padding: 16px;
  }

  .pdf-title {
    font-size: 18px;
  }

  .pdf-meta {
    gap: 6px 14px;
  }

  .pdf-meta .meta-item {
    font-size: 13px;
  }

  .pdf-download-section {
    flex-direction: column;
    gap: 16px;
  }

  .pdf-cover {
    width: 160px;
    margin: 0 auto;
  }

  .pdf-download-btn {
    font-size: 15px;
    padding: 12px 24px;
  }

  .toc-body {
    grid-template-columns: 1fr;
    gap: 16px;
  }
}

@media (max-width: 480px) {
  .pdf-card {
    padding: 12px;
  }

  .pdf-title {
    font-size: 17px;
  }

  .pdf-cover {
    width: 140px;
  }

  .pdf-download-btn {
    font-size: 14px;
    padding: 10px 20px;
  }

  .file-info-row {
    font-size: 13px;
    flex-wrap: wrap;
  }

  .gallery-item {
    max-width: 100%;
  }

  .pdf-nav {
    flex-direction: column;
    gap: 10px;
  }
}