html {
    box-sizing: border-box;
}
  
*, *:before, *:after {
    box-sizing: inherit;
}
  
 body {
    min-height: 100vh;
    margin: 0; /* Important! */
    font-family: sans-serif;
    background: url(https://w0.pngwave.com/png/395/324/train-heartnet-black-cat-anime-manga-anime-cat-png-clip-art.png);
    background-size: cover
 }
  
.wrapper {
    margin: 0 auto;
    max-width: 500px;
    font-size: 20px;
    line-height: 2;
    position: relative;
}
  
a {
    text-decoration: none;
    color: black;
    background: rgba(0,0,0,0.05);
    border-radius: 20px;
}
  
.highlight {
    transition: all 0.2s;
    border-bottom: 2px solid white;
    position: absolute;
    top: 0;
    background: white;
    left: 0;
    z-index: -1;
    border-radius: 20px;
    display: block;
    box-shadow: 0 0 10px rgba(0,0,0,0.2);
}
  
.menu {
    padding: 0;
    display: flex;
    list-style: none;
    justify-content: center;
    margin:100px 0;
}
  
.menu a {
    display: inline-block;
    padding: 5px;
    margin: 0 20px;
    color: black;
}