@font-face {
  font-family: 'MyCustomFont';
  src: url('./font/fontdownload.woff2') format('woff2'), /* 最优先级 */
       url('./font/fontdownload.woff') format('woff'),   /* 其次优先级 */
       url('./font/fontdownload.ttf') format('truetype'); /* 最后优先级，兼容旧浏览器 */
}