style.css

body{
    background: #000; 
    color: yellow;
    font-family: 'Trebuchet MS', 'Lucida Sans Unicode', 'Lucida Grande', 'Lucida Sans', Arial, sans-serif;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 14px;
}

h1{
    font-family: monospace;
    font-weight: 200;
    font-size: 3rem;
    margin-bottom: -10px;
    color: rgb(216, 204, 31);
}

h2{
    font-family: monospace;
    font-weight: 50;
    font-size: 1.7rem;
    margin-bottom: -25px;
    color: rgb(216, 204, 31);
}

h3{
    font-family: monospace;
    font-weight: 50;
    font-size: 1rem;
    margin-bottom: 2px;
    color: rgb(216, 204, 31);
}

label{
    font-size: 1.2rem;
    font-weight: 600;
}

input{
    max-width: 350px;
    width: 90%;
    height: 30px;
    border-radius: 20px;
    background: #575508;
    padding: 5px;
    font-size: 1.7rem;
    font-family: sans-serif;
    color: rgb(36, 35, 34);
    text-align: center;
}

img{
    width: 90%;
    max-width: 350px;
    margin-top: 30px;
    border-radius: 10px;
}

/* CSS */
.button-85 {
    padding: 0.6em 2em;
    border: none;
    outline: none;
    color: rgb(255, 255, 255);
    background: #111;
    cursor: pointer;
    position: relative;
    z-index: 0;
    border-radius: 10px;
    user-select: none;
    -webkit-user-select: none;
    touch-action: manipulation;
}

.button-85: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);
    -webkit-filter: blur(5px);
    width: calc(100% + 4px);
    height: calc(100% + 4px);
    animation: glowing-button-85 20s linear infinite;
    transition: opacity 0.3s ease-in-out;
    border-radius: 10px;
}

@keyframes glowing-button-85 {
    0% {
    background-position: 0 0;
    }
    50% {
    background-position: 400% 0;
    }
    100% {
    background-position: 0 0;
    }
}

.button-85:after {
    z-index: -1;
    content: "";
    position: absolute;
    width: 100%;
    height: 100%;
    background: #222;
    left: 0;
    top: 0;
    border-radius: 10px;
}