/* base.css — 全局重置、字体、基础容器与可访问性基线 */
  *{margin:0;padding:0;box-sizing:border-box}
  body{
    font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
    background:#f5f7fb;color:#0f172a;-webkit-font-smoothing:antialiased;
    line-height:1.6;
  }
  a{text-decoration:none;color:inherit}
  button{font-family:inherit}
  button, a, [role="button"]{ -webkit-tap-highlight-color:transparent; }
  :focus-visible{ outline:2px solid #2563eb; outline-offset:2px; border-radius:8px; }
  .container{max-width:1080px;margin:0 auto;padding:0 20px}
  [hidden]{display:none!important}