style.css

::-webkit-inner-spin-button {
    display: none;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    color: #5051fb;
    user-select: none;
}

body {
    width: 100vw;
    height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;

}

#info-container {
    width: 80%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 10px;
}

#settings-button {
    width: 25px;
    height: 100%;
    fill: #5051fb;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

#settings-button:hover #settings-container {
    transform: scale(1);
}

#settings-container {
    top: 100%;
    left: 0;
    width: 200px;
    height: 300px;
    position: absolute;
    padding: 15px;
    transform-origin: top left;
    transform: scale(0);
    transition: 0.5s;
}

#settings-container label {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 15px;
}

#settings-container label input {
    width: 15%;
    border: none;
    border-bottom: 1px solid #5051fb;
    outline: none;
}


#start-game {
    padding: 5px 10px;
    border-radius: 15px;
    background-color: #5051fb;
    border: none;
    outline: none;
    color: white;
    cursor: pointer;
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
}

#game-container {
    width: 80%;
    height: 80%;
    display: flex;
    flex-wrap: wrap;
    border: 1px solid #5051fb;
}

#game-container>div {
    --width: calc(100% / var(--columnCount));
    --height: calc(100% / var(--rowCount));
    width: clamp(var(--width), var(--width), var(--width));
    height: clamp(var(--height), var(--height), var(--height));
    display: block;
}

.container {
    border-radius: 10px;
    box-shadow: rgba(0, 0, 0, 0.16) 0px 10px 36px 0px, rgba(0, 0, 0, 0.06) 0px 0px 0px 1px;
    background-color: white;
    overflow: hidden;
}