body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #f5f5f5;
}
header {
  background: #7B98C0;
  color: #fff;
  text-align: center;
  padding: 1em 0;
  font-size: 1.5em;
}
main {
  max-width: 900px;
  margin: 2em auto;
  background: #fff;
  padding: 2em;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}
section {
  margin-bottom: 2em;
}
input[type="file"] {
  margin-right: 1em;
}
button {
  font-size: 1em;
  padding: 0.5em 1.2em;
  border: none;
  border-radius: 4px;
  background: #1976d2;
  color: #fff;
  margin: 0 0.3em;
}
table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1em;
}
th, td {
  border: 1px solid #ddd;
  padding: 0.7em 0.5em;
  text-align: left;
}
th {
  background: #f0f0f0;
}

/* 文字居中样式 */
.text-center {
  text-align: center;
}

.admin-content {
  text-align: center;
}

.admin-content > * {
  text-align: center;
}

/* PDF操作按钮组 */
.pdf-actions {
  display: flex;
  flex-direction: column;
  gap: 12px;
  align-items: center;
  width: 100%;
  margin-top: 0.5em;
  justify-content: center;
}

/* 统一按钮基础样式 */
.btn-share, .btn-delete, .btn-copy {
  width: 100%;
  height: 44px;
  line-height: 44px;
  font-size: 1.08em;
  border-radius: 6px;
  padding: 0 0.5em;
  display: block;
  margin: 0;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-align: center;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: all 0.2s ease;
  box-sizing: border-box;
}

/* 上传表单按钮 */
#choose-file-btn,
#upload-form button {
  height: 44px;
  line-height: 44px;
  font-size: 1.08em;
  border-radius: 6px;
  padding: 0 0.5em;
  display: block;
  margin: 0 0 12px 0;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-align: center;
}

/* View按钮样式 */
.btn-share {
  background: #10b981;
  color: #fff;
}

.btn-share:hover {
  background: #059669;
}

/* 复制按钮样式 */
.btn-copy {
  background: #3b82f6;
  color: #fff;
}

.btn-copy:hover {
  background: #2563eb;
}

/* 删除按钮样式 */
.btn-delete {
  background: #ef4444;
  color: #fff;
}

.btn-delete:hover {
  background: #dc2626;
}

/* 移除多余间距，按钮组内最后一个按钮无下边距 */
.pdf-actions .btn-delete:last-child,
.pdf-actions .btn-copy:last-child,
.pdf-actions .btn-share:last-child,
#upload-form button:last-child {
  margin-bottom: 0;
}