style.css

@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@100;200;300;400;500;600;700;800&display=swap');
*{
    box-sizing: border-box;
    margin:0;
    padding:0;    
    font-family: 'Poppins', sans-serif;
}
h1{
    top:0;
    text-align: center;
}
body{
    background: #DCDCDC;
}
section{
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    flex-wrap: wrap;
    transform-style: preserve-3d;
}

section .card{
    position: relative;
    width: 320px;
    height: 320px;
    margin: 20px;
    transform-style: preserve-3d;
    perspective: 1000px;
}

section .card .box{
    position: absolute;
    top:0;
    left:0;
    width: 100%;
    height: 100%;
    transform-style:preserve-3d ;
    transition: 1s ease;
}
section .card:hover .box{
    transform: rotateY(180deg);
}
section .card .box .imgBx{
    position: absolute;
    top:0;
    left:0;
    width: 100%;
    height: 100%;
}
section .card .box .imgBx img{
    position: absolute;
    top:0;
    left:0;
    width: 100%;
    height: 100%;
    object-fit: cover;
}
section .card .box .contentBx{
    position: absolute;
    top:0;
    left:0;
    width: 100%;
    height: 100%;
    background: #333;
    backface-visibility: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    transform-style: preserve-3d;
    transform: rotateY(180deg);
}

section .card .box .contentBx div{
    transform-style: preserve-3d;
    padding: 20px;
    background: linear-gradient(45deg,#f30061,#ffeb3b);
    transform: translateZ(240px);
}

section .card .box .contentBx div h2{
    color:#fff;
    font-size: 20px;
    letter-spacing: 1px;
}

section .card .box .contentBx div p{
    color: #fff;
    font-size: 16px;
}