#intro_banner {
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    min-height: 100vh;
    color: #aaa;
}
body {
    margin: 0;
    font-family: Arial, Helvetica, sans-serif;
}
.topnav {
    overflow: hidden;
}
.topnav > a {
    /* float: left; */
    color: #f2f2f2;
    text-align: center;
    padding: 14px 16px;
    text-decoration: none;
    font-size: 17px;
}
.topnav > a:hover {
    text-decoration: none;
    color: rgba(255, 255, 255, 0.979);
    text-shadow: 0 0 20px #fff, 0 0 40px silver, 0 0 60px silver,
        0 0 80px silver, 0 0 90px silver, 0 0 100px silver, 0 0 120px silver;
}

.imgs {
    display: grid;
    grid-template-columns: 25% 25% 25% 25%;
    justify-content: center;
    height: auto;
}
div.img {
    display: flex;
    flex-direction: column;
    width: 100%;
}
img {
    display: flex;
    flex-direction: column;
    width: 100%;
}