style.css

body {
    font-family: poppins, arial, helvetica, sans-serif;
    background-color: rgb(141, 141, 141);
    display: grid;
    place-content: center;
    min-height: 100vh;
}

#grid-container {
    display: grid;
    height: 50vw;
    width: 50vw;
    background-color: white;
    gap: 0.5em;
    padding: 0.5em;
}

#grid-container>div {
    display: grid;
    border: 1px solid blue;
    border-radius: 0.2em;
    place-content: center;
    transition-duration: 0.5s;
}

#grid-container>div:nth-child(1) {
    grid-column: 1/5;
    grid-row: 1/5;
}

#grid-container>div:nth-child(2) {
    grid-column: 5/7;
    grid-row: 1/3;
}

#grid-container>div:nth-child(3) {
    grid-column: 7/9;
    grid-row: 1/3;
}

#grid-container>div:nth-child(4) {
    grid-column: 5/7;
    grid-row: 3/5;
}

#grid-container>div:nth-child(5) {
    grid-column: 7/9;
    grid-row: 3/5;
}

#grid-container>div:nth-child(6) {
    grid-column: 1/3;
    grid-row: 5/7;
}

#grid-container>div:nth-child(7) {
    grid-column: 3/7;
    grid-row: 5/7;
}

#grid-container>div:nth-child(8) {
    grid-column: 7/9;
    grid-row: 5/9;
}

#grid-container>div:nth-child(9) {
    grid-column: 1/5;
    grid-row: 7/9;
}

#grid-container>div:nth-child(10) {
    grid-column: 5/7;
    grid-row: 7/9;
}

#grid-container>div:hover {
    background-color: blue;
    color: white;
    transition-duration: 0.5s;
}