* {
    margin: 0px;
    padding: 0px;
    box-sizing: border-box;
}

body {
    font-family: 'Poppins', sans-serif;
    background-color: #111;
}
button {
    font-family: 'Poppins', sans-serif;
}

header {
    display: flex;
    width: 90%;
    height: 10vh;
    margin: auto;
    align-items: center;
}

.logo-container,
.nav-links,
.cart {
    display: flex;
}

.logo-container {
    flex: 1;
}
.logo {
    font-weight: 400;
    margin: 5px;
}
nav {
    flex: 2;
}
.nav-links {
    justify-content: space-around;
    list-style: none;
}
.nav-link {
    color: #acacac;
    font-size: 20px;
    font-weight: 900;
    font-family: Arial, Helvetica, sans-serif;
    filter: drop-shadow(0px 0px 0px rgb(255, 0, 128));
    text-decoration: none;
    animation: drop 1.5s ease-in-out;
}
.nav-link::after{
    content: '';
    height: 5px;
    width: 0;
    background: #ff8aef;
    position: absolute;
    left: 0;
    bottom: -5px;
    transition: 0.5s;
}
.nav-link:hover::after{
    width: 100%;
}
.cart {
    flex: 1;
    justify-content: flex-end;
}

.presentation {
    display: flex;
    width: 90%;
    margin: auto;
    min-height: 80vh;
    align-items: center;
}
.introduction {
    flex: 1;
}
#shadowBox {
    background-color: rgb(0, 0, 0);
    /* Fallback color */
    background-color: rgba(0, 0, 0, 0.2);
    /* Black w/opacity/see-through */
    border: 3px solid;
}

.intro-text {
    text-align: center;
    text-decoration: underline;
    font-size: 25px;
    font-family: monospace;
    letter-spacing: 2px;
}
.intro-text {
    background: linear-gradient(to right, #6666ff, #0099ff , #00ff00, #ff3399, #6666ff);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    animation: rainbow_animation 6s ease-in-out infinite;
    background-size: 400% 100%;
}

@keyframes rainbow_animation {
    0%,100% {
        background-position: 0 0;
    }

    50% {
        background-position: 100% 0;
    }
}
.intro-text p {
    margin-top: 5px;
    font-size: 22px;
    color: #585772;
    animation: drop 1.5s ease;
}
.cta {
    padding: 50px 0px 0px 0px;
}
.glow-on-hover {
    width: 300px;
    height: 50px;
    border: none;
    outline: none;
    color: #fff;
    background: #111;
    cursor: pointer;
    position: relative;
    left: 200px;
    z-index: 0;
    border-radius: 10px;
    font-size: 17px;
}

.glow-on-hover: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;
}

.glow-on-hover {
    color: #000
}
.glow-on-hover:before {
    opacity: 1;
}

.glow-on-hover:active {
    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; }
}
.cover {
    flex: 1;
    display: flex;
    justify-content: center;
    height: 60vh;
}
.cover img {
    height: 100%;
    filter: drop-shadow(0px 8px 3px rgb(255, 0, 128));
    animation: drop 1.5s ease;
}

.big-circle {
    position: absolute;
    top: 0px;
    right: 0px;
    z-index: -1;
    height: 80%;
    animation: drop 0.5s ease;
}
.medium-circle {
    position: absolute;
    top: 40%;
    right: 25%;
    z-index: -1;
    height: 60%;
    animation: drop 0.7s ease;
}
.small-circle {
    position: absolute;
    bottom: 0%;
    left: 20%;
    z-index: -1;
    animation: drop 0.8s ease;
}

@keyframes drop {
    0% {
        opacity: 0;
        transform: translateY(-80px);
    }
    100% {
        opacity: 1;
        transform: translateY(0px);
    }
}

@media screen and (max-width: 1024px) {
    .presentation {
        flex-direction: column;
    }
    .introduction {
        margin-top: 5vh;
        text-align: center;
    }
    .intro-text h1 {
        font-size: 30px;
    }
    .intro-text p {
        font-size: 18px;
    }
    .cta {
        padding: 10px 0px 0px 0px;
    }
    .cover img {
        height: 80%;
    }
    .small-circle,
    .medium-circle,
    .big-circle {
        opacity: 0.2;
    }
}