* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    transition: background 0.5s ease;
}

body div#a{
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100vw;
    height: 100vh;
}

input {
    outline: none;
    border: 1px solid #ccc;
    padding: 5px;
    transition: font-size 0.5s ease-in-out;
    border-radius: 5px;
    opacity: 0.8;
}

input#b{
    color: #979595;
    font-size: 1rem;
}

/* Class to be added via JavaScript */
.special-bg {
  background-image: url('https://static.wikia.nocookie.net/duelmasters/images/b/b4/Terror_Pit.jpg/');
  background-size: cover;
  background-position: center;/* Makes the image fill the whole area without stretching */
  background-size: cover; 
  
  /* Keeps the image in the center so the edges get cropped evenly */
  background-position: center; 
  
  /* Stops the image from repeating if it's too small */
  background-repeat: no-repeat; 
  
  /* Keeps the image still when you scroll (optional, but looks pro) */
  background-attachment: fixed;
}