css 判断是iphone4s

/* 兼容iphone4/4s */
@media only screen and (device-width: 320px) and (device-height: 480px) and (-webkit-device-pixel-ratio: 2) {
  .container {
    top: 45%;
  }
}

js判断是否是iphone4s

if (window.screen && window.screen.height === 480 && window.screen.width === 320 && navigator.userAgent.indexOf("iPhone") > -1) {
  // console.log("iPhone4/4s");
}

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