Default CSS for the sync buttons and pop-ups. Click here to check the default layout.

<style>
  .lvs-dialog {
    position: fixed;
    bottom: 0;
    left: 0;
    font-size: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    animation: showBox 0.3s;
  }
  @keyframes showBox {
    from {
      opacity: 0;
    }
    to {
      opacity: 1;
    }
  }

  // mobile

  .lvs-sync-btn {
    display: inline-block;
    width: 64vw;
    height: 40px;
    background: linear-gradient(45deg, #ff607f 20%, #fe2588 100%);
    color: #fff;
    font-size: 14px;
    line-height: 40px;
    text-align: center;
    box-shadow: 0 4px 10px -3px rgba(215, 0, 114, 0.5);
    border-radius: 6px;
  }

  .lvs-box-content {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 373px;
    text-align: center;
    background-color: #fff;
    animation: lvsshowContent 0.3s;
    border-radius: 18px 18px 0 0;
    overflow: hidden;
  }
  @keyframes lvsshowContent {
    from {
      height: 0;
    }
    to {
      height: 373px;
    }
  }
  .lvs-close-box {
    position: absolute;
    right: 20px;
    top: 20px;
    width: 18px;
    height: 18px;
  }
  .lvs-box-title {
    margin-top: 40px;
    font-size: 17px;
    font-weight: 600;
    color: #333;
    line-height: 22px;
  }
  .lvs-remote-box {
    display: block;
    margin-top: 30px;
    margin-left: 50%;
    text-align: center;
    transform: translateX(-50%);
  }
  .lvs-remote-icon {
    width: 50px;
    height: 50px;
  }
  .lvs-remote-title {
    font-size: 14px;
    font-weight: 600;
    margin-top: 8px;
    margin-bottom: 20px;
    line-height: 17px;
  }
  .lvs-success-icon {
    display: block;
    margin-left: 50%;
    margin-top: 30px;
    width: 84px;
    height: 84px;
    transform: translateX(-50%);
  }
  .lvs-toys-tips {
    width: 100%;
    padding: 0 44px;
    margin-top: 20px;
    font-size: 15px;
    color: #333;
    box-sizing: border-box;
  }
  .lvs-unsync-btn {
    margin-top: 16px;
    margin-left: 50%;
    width: 200px;
    line-height: 40px;
    color: #fff;
    font-size: 14px;
    font-weight: 600;
    background: linear-gradient(45deg, #ff607f 20%, #fe2588 100%);
    box-shadow: 0 8px 20px -6px rgba(215, 0, 114, 0.5);
    border-radius: 6px;
    overflow: hidden;
    transform: translateX(-50%);
  }
  .lvs-go-back {
    width: 100%;
    margin-top: 30px;
    font-size: 12px;
    line-height: 14px;
    color: #333;
    text-decoration: underline;
  }

  // pc

  .lvs-pc-box-content {
    position: fixed;
    top: 50%;
    left: 50%;
    width: 400px;
    height: 404px;
    text-align: center;
    background-color: #fff;
    animation: lvspcshowContent 0.3s;
    transform: translate(-50%, -50%);
    border-radius: 8px;
    overflow: hidden;
  }
  @keyframes lvspcshowContent {
    from {
      transform: translate(-50%, -50%) scale(0);
    }
    to {
      transform: translate(-50%, -50%) scale(1);
    }
  }
  .lvs-pc-close-box {
    position: absolute;
    right: 20px;
    top: 20px;
    width: 18px;
    height: 18px;
    cursor: pointer;
  }
  .lvs-pc-close-box:hover {
    opacity: 0.6;
  }
  .lvs-pc-box-title {
    margin-top: 40px;
    line-height: 24px;
    font-size: 18px;
    color: #333;
    font-weight: 600;
  }
  .lvs-pc-success-icon {
    display: block;
    margin-top: 32px;
    margin-left: 50%;
    width: 120px;
    height: 120px;
    transform: translateX(-50%);
  }
  .lvs-pc-toys-tips {
    margin-top: 24px;
    font-size: 14px;
    color: #333;
    line-height: 20px;
  }
  .lvs-pc-unsync-btn {
    margin-top: 12px;
    margin-left: 50%;
    width: 160px;
    line-height: 36px;
    color: #fff;
    font-size: 14px;
    font-weight: 600;
    background: linear-gradient(45deg, #ff607f 20%, #fe2588 100%);
    box-shadow: 0 8px 20px -6px rgba(215, 0, 114, 0.5);
    border-radius: 8px;
    overflow: hidden;
    transform: translateX(-50%);
    cursor: pointer;
  }
  .lvs-pc-unsync-btn:hover {
    opacity: 0.6;
  }
  .lvs-pc-go-back {
    width: 100%;
    margin-top: 58px;
    font-size: 12px;
    color: #333;
    text-decoration: underline;
    cursor: pointer;
  }
  .lvs-pc-go-back:hover {
    opacity: 0.6;
  }
  .lvs-pc-title {
    margin-top: 32px;
    font-size: 14px;
    color: #333;
    line-height: 20px;

    span {
      font-weight: 600;
    }
  }
  .lvs-pc-qrcodebox {
    width: 100%;
    margin-top: 34px;
    display: flex;
    justify-content: center;
    align-items: center;
  }
  .lvs-pc-qrcode {
    margin: 0 16px;
    width: 120px;
    height: 120px;
  }
  .lvs-pc-phone {
    margin: 0 16px;
    width: 128px;
    height: 182px;
  }
  .lvs-pc-sync-btn {
    display: inline-block;
    width: 270px;
    height: 44px;
    background: linear-gradient(45deg, #ff607f 20%, #fe2588 100%);
    color: #fff;
    font-size: 16px;
    line-height: 44px;
    text-align: center;
    box-shadow: 0 4px 10px -3px rgba(215, 0, 114, 0.5);
    cursor: pointer;
  }
  .lvs-pc-sync-btn:hover {
    opacity: 0.6;
  }

  // If you want to use icons instead of buttons to trigger the sync function, please use the code below, and change the icon as desired.
  
  // mobile
  .lvs-sync-btn {
    position: relative;
    display: inline-block;
    width: 30px;
    height: 30px;
    font-size: 0;
    background: none;
    background-image: url("https://cdn.lovense.com/resources/img/app_logo.png");
    background-size: 100% 100%;
    box-shadow: none;
    cursor: pointer;
  }

  .lvs-sync-btn::after {
    content: "SYNC";
    position: absolute;
    top: 0;
    right: 0;
    padding: 3px 8px;
    line-height: 13px;
    font-size: 10px;
    color: #fff;
    text-align: center;
    background: #ff2d89;
    border-radius: 13.5px;
    transform: translate(50%, -50%);
  }

  .lvs-sync-btn.lvs-synced::after {
    content: "UNSYNC";
    position: absolute;
    top: 0;
    right: 0;
    padding: 3px 8px;
    line-height: 13px;
    font-size: 10px;
    color: #fff;
    text-align: center;
    background: #ff2d89;
    border-radius: 13.5px;
    transform: translate(50%, -50%);
  }

  // pc

  .lvs-pc-sync-btn {
    position: relative;
    display: inline-block;
    width: 30px;
    height: 30px;
    font-size: 0;
    background: none;
    background-image: url("https://cdn.lovense.com/resources/img/app_logo.png");
    background-size: 100% 100%;
    box-shadow: none;
    cursor: pointer;
  }

  .lvs-pc-sync-btn::after {
    content: "SYNC";
    position: absolute;
    top: 0;
    right: 0;
    padding: 3px 8px;
    line-height: 13px;
    font-size: 10px;
    color: #fff;
    text-align: center;
    background: #ff2d89;
    border-radius: 13.5px;
    transform: translate(50%, -50%);
  }

  .lvs-pc-sync-btn.lvs-synced::after {
    content: "UNSYNC";
    position: absolute;
    top: 0;
    right: 0;
    padding: 3px 8px;
    line-height: 13px;
    font-size: 10px;
    color: #fff;
    text-align: center;
    background: #ff2d89;
    border-radius: 13.5px;
    transform: translate(50%, -50%);
  }
</style>