body {
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100vh;
}
 
h1 {
    font-size: 6em;
    margin-bottom: 20px;
}
 
.bingo-card {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    grid-template-rows: repeat(5, 1fr);
    gap: 5px;
    width: 90vw;
    max-width: 800px;
    height: 90vw;
    max-height: 400px;
    border: 2px solid black;
    padding: 5px;
    box-sizing: border-box;
}
 
.bingo-column {
    display: flex;
    flex-direction: column;
}
 
.bingo-cell {
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid black;
    cursor: pointer;
    font-size: 4em;
    width: calc(100% - 1px);
    height: calc(100% - 1px);
}
 
.bingo-cell.center {
    background-color: lightgreen;
}
 
.marked {
    background-color: pink;
}