H5页面文字和按钮在不同设备上位置偏移：如何解决？

.share {
  width: 100%;
  height: 100%;
  background: url("./img/bg.png") no-repeat;
  overflow: hidden;
  background-size: 100% 100%; 
  image-rendering: -moz-crisp-edges; /* Firefox */
  image-rendering: -o-crisp-edges; /* Opera */
  image-rendering: -webkit-optimize-contrast; /*Webkit (non-standard naming)*/
  image-rendering: crisp-edges;
  -ms-interpolation-mode: nearest-neighbor;
  position: relative;
}
.title {
  position: absolute;
  left: 50%;
  bottom: 24%;
  transform: translate(-50%, -50%);
  width: 100%;
  font-size: 1rem;
  font-weight: 700;
  color: #333;
  text-align: center;
  letter-spacing: 1px;
}
.btn {
  position: absolute;
  left: 50%;
  bottom: 15%;
  transform: translate(-50%, -50%);
  background: #fd4a08;
  height: 36px;
  display: flex;
  align-items: center;
  border-radius: 20px;
  font-size: .16rem;
  color: #fff;
  width: 40%; /* 问题所在 */
}
.btn img {
  width: 40px;
  height: 20px;
  padding-left: 14px;
}
.btn .app {
  padding-left: 10px;
}
.btn .open {
  padding-left: 3px;
}