app.css

/* Here goes the common css for all the pages */



@font-face {
    font-family: Neonblitz;
    font-style: normal;
    font-weight: 400;
    src: local('Neonblitz'), url(https://fonts.cdnfonts.com/s/54108/Neonblitz-Yzg8O.woff) format('woff')
}

* {
    --slide-animation-time: 500ms;
}

body {
    font-size: 18px;
    background-color: #010a01;
    margin: 0;
}

.header {
    font-family: Neonblitz, sans-serif;
    display: flex;
    gap: 20px;
    background-color: rgb(33, 37, 41);
    padding: 15px;
    position: sticky;
    z-index: 1;
}

.header a {
    text-decoration: none;
    color: #ccc;
}

.nav-options {
    display: flex;
    gap: 20px;
}

.header a:hover {
    color: #fff;
}


#three-bars {
    display: none;
    color: #888;
    transform: scale(2);
    right: 0;
    position: absolute;
    margin-right: 30px;
    border-radius: 2px;
    padding: 1px 3px;
    border: 1px solid #88888870;
}

#three-bars:hover {
    border: 1px solid #888888;
    outline: 0;
    cursor: pointer;
}

@media only screen and (max-width: 990px) {
    #three-bars {
        display: block;
    }

    .nav-options {
        top: 50px;
        position: absolute;
        background-color: inherit;
        width: 100%;
        left: 0;
        transition: height var(--slide-animation-time);
        height: 0;
        flex-direction: column;
        overflow: hidden;
    }

    .nav-options a{
        margin-left: 15px;
    }
}


#cards-grid{
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    max-width: 1050px;
    justify-content: center;
}

.card{
    width: 200px;
    height: 200px;
    background-color: #ddd;
    transition: transform 500ms;
    font-family: Verdana, Geneva, Tahoma, sans-serif;
    text-align: center;
}

.card_signal{
    transition: transform 500ms;
    transform-style: preserve-3d;
    width: 100%;
    height: 100%;
}

.card:hover .card_signal{
    transform: rotateY(180deg);
}

.card_front, .card_back{
    position: absolute;
    backface-visibility: hidden;
    display: flex;
    justify-content: center;
    flex-direction: column;
    align-items: center;
    width: 100%;
    height: 100%;
}

.card_back{
    transform: rotateY(180deg);
}


.card_front span, .card_front img, .card_back span, .card_back img{
    display: block;
}