.fixed-element {
  position: absolute;
  z-index: 10;
}

.hover-switch {
  position: relative;
  display: inline-block;
  width: 111px;
  height: 26px;
}

.hover-switch img {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  transition: opacity .2s ease;
}

.hover-switch .hover {
  opacity: 0;
}

.hover-switch:hover .normal,
.hover-switch:focus .normal {
  opacity: 0;
}

.hover-switch:hover .hover,
.hover-switch:focus .hover {
  opacity: 1;
}

.hover-switch:focus {
  outline: 3px dashed #000;
  outline-offset: 2px;
}

@media (max-width: 600px) {
  .fixed-element {
    position: static;
    margin: 10px auto;
    text-align: center;
  }

  .hover-switch {
    width: 90px;
    height: 22px;
  }
}

    #topButton {
      position: fixed;
      bottom: 20px;
      right: 20px;
      z-index: 100;
      background-color: #333;
      color: white;
      border: none;
      padding: 10px 15px;
      border-radius: 5px;
      cursor: pointer;
      font-size: 18px;
      display: none;
    }

    #topButton:hover {
      background-color: #555;
    }