body {
  font-family:
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
    "WenQuanYi Micro Hei", "Noto Sans CJK SC", "Source Han Sans SC",
    "Helvetica Neue", Arial, sans-serif, "KaiTi", "楷体";
  font-size: 16px; /* 推荐用 px 而非 pt，更符合网页标准 */
  line-height: 1.6; /* 行高增加可读性 */
  text-rendering: optimizeLegibility; /* 优化字体渲染 */
}