@keyframes bouncing {
  0% {
    top: 0px;
  }
  25% {
    top: -2px;
  }
  50% {
    top: 0px;
  }
  75% {
    top: 2px;
  }
  100% {
    top: 0px;
  }
}

/* Default za telefon (mobile-first) */
.scroll_to_top img {
  width: 20px;
  height: 20px;
}
.scroll_to_top {
  display: flex;
  justify-content: center;
  align-items: center;
  position: fixed;
  top: 70%;
  left: 80%;

  padding: 18px;

  background-color: #f4eade;
  box-sizing: border-box;
  border: 2px solid #faf9f8;

  border-radius: 100%;

  cursor: pointer;
  z-index: 50;

  opacity: 0;
  pointer-events: none;
  transition: 0.4s all;
}

.scroll_to_top:active img {
  position: relative;
  animation: bouncing 0.5s linear infinite;
  transform: scale(1.1);
}
.show_btn {
  opacity: 1;
  pointer-events: auto;
  top: 85%;
}

/* Veći ekran (npr. tablet) */
@media (min-width: 768px) {
  .scroll_to_top img {
    width: 30px;
    height: 30px;
  }
  .scroll_to_top {
    left: 90%;

    padding: 20px;

    border: 3px solid #faf9f8;
  }

  .show_btn {
    top: 75%;
  }
}

/* Još veći ekran (npr. desktop) */
@media (min-width: 1200px) {
  .scroll_to_top img {
    width: 40px;
    height: 40px;
  }
  .scroll_to_top {
    padding: 20px;
    border: 5px solid #faf9f8;
  }

  .scroll_to_top:active img {
    position: relative;
    animation: bouncing 0.5s linear infinite;
    transform: scale(1.1);
  }
  .show_btn {
    opacity: 1;
    pointer-events: auto;
    top: 85%;
  }
}