* {
    box-sizing: border-box
}

:root {
    --main-color: #fff
}

body {
    margin: 0;
    font-family: sans-serif;
    background: linear-gradient(130deg, #5f0dda, #225bde, #079cba, #079cba, #225bde, #5f0dda);
    background-size: 1200% 1200%;
    animation: AnimationName 10s ease-in-out infinite;
    color: var(--main-color);
}

@keyframes AnimationName {
    0% {
        background-position: 0% 51%
    }

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

    100% {
        background-position: 0% 51%
    }
}

.box-area {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    margin: 0;
    z-index: -1;
}

.box-area li {
    position: absolute;
    display: block;
    list-style: none;
    width: 25px;
    height: 25px;
    background: rgba(255, 255, 255, 0.2);
    animation: animate 20s linear infinite;
    bottom: -150px;
}

.box-area li:nth-child(1) {
    left: 86%;
    width: 80px;
    height: 80px;
    animation-delay: 0s;
}

.box-area li:nth-child(2) {
    left: 12%;
    width: 30px;
    height: 30px;
    animation-delay: 1.5s;
    animation-duration: 10s;
}

.box-area li:nth-child(3) {
    left: 70%;
    width: 100px;
    height: 100px;
    animation-delay: 5.5s;
}

.box-area li:nth-child(4) {
    left: 42%;
    width: 150px;
    height: 150px;
    animation-delay: 0s;
    animation-duration: 15s;
}

.box-area li:nth-child(5) {
    left: 65%;
    width: 40px;
    height: 40px;
    animation-delay: 0s;
}

.box-area li:nth-child(6) {
    left: 15%;
    width: 110px;
    height: 110px;
    animation-delay: 3.5s;
}

@keyframes animate {
    0% {
        transform: translateY(0) rotate(0deg);
        opacity: 1;
    }

    100% {
        transform: translateY(-800px) rotate(360deg);
        opacity: 0;
    }
}

.container {
    max-width: 900px;
    margin: 0 auto
}

.text-center {
    text-align: center
}

.mt-4 {
    margin-top: 4rem
}

.main-heading {
    font-size: 3rem
}

.big-block {
    display: flex;
    align-items: center;
    justify-content: space-around
}

#text {
    font-size: 2rem;
    padding: 5px 15px;
    border-radius: 10px;
    border: 2px solid rgba(0, 0, 0, 0.2);
    outline: none
}

#button {
    background-color: rgb(33, 33, 92);
    color: var(--main-color);
    font-size: 2rem;
    padding: 5px 15px;
    border-radius: 10px;
    border-width: 2px;
    border-color: var(--main-color);
    cursor: pointer;
    outline: none
}

ul {
    
    list-style-type: "▶"
}

.list-group {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 5px;
    max-width: 400px;
    margin-block: 1rem;
    padding: 6px 10px
}

.list-group span {
    cursor: pointer;
    text-decoration: underline;
    transition: 0.3s ease-in-out;
    float: right;
}

.list-group span:hover {
    color: #151515;
}