body {
    background-image: linear-gradient(60deg, red, pink, rgb(255, 200, 240));
    color: black;
}

#first-paragraph {
    background-color: #ff0000;
    height: 100px;
    width: 450px;
    /* Can be combined */
    border-color: #000;
    border-width: 10px;
    border-style: double;
    border-radius: 20px;
    /* border: 10px solid double */
    margin: auto;
    border-top-style: solid;
    border-top-right-radius: 100px;
    border-bottom-left-radius: 100px;
    margin-bottom: 20px;
    padding: 20px;
    /* So the text doesn't overflow */
}

.card {
    display: table;
    top: 50px;
    position: relative;
    height: 450px;
    width: 50%;
    max-width: 300px;
    background-color: rgb(57, 52, 52);
    color: white;
    margin: auto;
    border-radius: 20px;
    transition: 1s;
}

.card::after {
    /*adds an rgb background behind the card*/
    --neg-border-width: -5px;
    position: absolute;
    top: var(--neg-border-width);
    bottom: var(--neg-border-width);
    left: var(--neg-border-width);
    right: var(--neg-border-width);
    background: linear-gradient(60deg, red, orange, blue, indigo, violet);
    content: '';
    /*this is important*/
    z-index: -1;
    border-radius: 25px;
    box-shadow: 0px 0px 100px 2px red;
    animation: rgb 4s infinite;
    transition: 1s;
    background-size: 200% 200%;
    background-position: 0% 50%;
    transition-timing-function: cubic-bezier(0.075, 0.82, 0.165, 1);
}

.wrapper {
    transition: 1s;
}

.wrapper:hover {
    scale: 1.1;
    margin-top: 50px;
    margin-bottom: 50px;
}

.card:hover::after {
    animation: rgb 4s infinite, rotate-bg 2s infinite;
    rotate: 15deg;
}

@keyframes rotate-bg {
    0% {
        background-position: 0% 50%;
    }

    50% {
        background-position: 100% 50%;
    }

    100% {
        background-position: 0% 50%;
    }
}

@keyframes rgb {
    0% {
        box-shadow: 0px 0px 100px 2px red;
    }

    20% {
        box-shadow: 0px 0px 100px 2px orange;
    }

    40% {
        box-shadow: 0px 0px 100px 2px blue;
    }

    60% {
        box-shadow: 0px 0px 100px 2px indigo;
    }

    80% {
        box-shadow: 0px 0px 100px 2px violet;
    }
}

.vertically-center {
    display: table-cell;
    text-align: center;
    vertical-align: middle;
}

div.background {
    width:fit-content;
    background-image: url(https://source.unsplash.com/featured/450x100);
    display: table;
    margin:auto;
}

#secondpara {
    font-size: x-large;
    mix-blend-mode: difference;
    background-color: rgb(0, 0, 0);
    color: rgb(255, 255, 255);
    height: 100px;
    width: 450px;
}

#thirdPara {
    text-align: center;
    font-size: x-large;
    height: 500px;
    background-image: url(https://source.unsplash.com/featured/100x100);
    /* try removing each of the below rules to see their effect */
    background-repeat: no-repeat;
    background-position: center center;
    background-size: 100%;
}