@font-face {
  font-family: 'manga';
  src: url('Fonts/manga-font/Manga-4vx6.ttf') format('truetype');
}

nav a{
    text-decoration: none;
}

.button-black {
    padding: 10px;
    margin-block: 10px;
    border: none;
    outline: none;
    color: #fff;
    background: #111;
    cursor: pointer;
    position: relative;
    z-index: 0;
    border-radius: 10px;
    font-family: 'manga';
    font-weight: 100;
    font-size: 25px;
}

.button-black:hover {
    background: rgb(116, 221, 213);
    color: #00FFFF;
    
}

.button-black:before {
    content: '';
    /* background: linear-gradient(45deg, #ff0000, #ff7300, #fffb00, #48ff00, #00ffd5, #002bff, #7a00ff, #ff00c8, #ff0000);  */
    position: absolute;
    top: -2px;
    left:-2px;
    background-size: 400%;
    z-index: -1;
    filter: blur(5px);
    width: calc(100% + 4px);
    height: calc(100% + 4px);
    /*animation: glowing 20s linear infinite;*/
    opacity: 0;
    transition: opacity .3s ease-in-out;
    border-radius: 10px;
}

.button-black:active {
    color: #000
}

.button-black:active:after {
    background: transparent;
}

.button-black:hover:before {
    opacity: 1;
}

.button-black:after {
    z-index: -1;
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background: #111;
    left: 0;
    top: 0;
    border-radius: 10px;
}

@keyframes glowing {
    0% { background-position: 0 0; }
    50% { background-position: 400% 0; }
    100% { background-position: 0 0; }
}