.link-underline {
    border-bottom-width: 0;
    background-image: linear-gradient(transparent, transparent), linear-gradient(#fff, #fff);
    background-size: 0 1px;
    background-position: 0 100%;
    background-repeat: no-repeat;
    transition: background-size .5s ease-in-out;
}

.link-underline-indigo {
    background-image: linear-gradient(transparent, transparent), linear-gradient(#7e22ce, #7e22ce)
}

.link-underline:hover {
    background-size: 100% 2px;
    background-position: 0 100%
}

.image-glow:hover img {
    filter: drop-shadow(0 0 10px rgba(255, 255, 255, 0.8));
}

.image-glow img {
    transition: filter 0.1s ease-in-out;
}

.text-glow:hover {
    text-shadow: 0 0 10px rgba(255, 255, 255, 0.8);
}

.text-glow {
    transition: text-shadow 0.1s ease-in-out;
}

.image-shadow img {
      filter: drop-shadow(0 0 10px rgba(0, 0, 0, 0.8));
}

#scrollToTopBtn {
    display: none;
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 99;
    font-size: 18px;
    border: none;
    outline: none;
    background-color: #555;
    color: white;
    cursor: pointer;
    padding: 15px;
    border-radius: 4px;
    opacity: 0;
    transition: opacity 0.3s ease-in-out;
  }
  
  #scrollToTopBtn:hover {
    background-color: #333;
  }
  
  #scrollToTopBtn.show {
    display: block;
    animation: fadeIn 0.3s ease-in-out forwards;
  }
  
  #scrollToTopBtn.hide {
    animation: fadeOut 0.3s ease-in-out forwards;
  }
  
  @keyframes fadeIn {
    0% {
      opacity: 0;
    }
    100% {
      opacity: 1;
    }
  }
  
  @keyframes fadeOut {
    0% {
      opacity: 1;
    }
    100% {
      opacity: 0;
      display: none;
    }
  }