body 
{
    margin: 0;
    font-family: Arial, sans-serif;
}

#loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: #fff;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 24px;
    z-index: 1000;
}

#idle-screen, #game-container, #win-screen, #lose-screen {
    display: none;
}

#game-container 
{
    display: none;
    width: 100vw;
    height: 100vh;
    background-size: cover;
    background-position: center;
    position: relative;
}

#cards 
{
    display: grid;
    gap: 10px;
    justify-content: center;
    align-items: center;
    width: 100%;
    height: 100%;
    grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
}

.card 
{
    width: 100px;
    height: 150px;
    background-size: cover;
    background-position: center;
    cursor: pointer;
    perspective: 1000px;
    position: relative;
}

.card .front,
.card .back 
{
    width: 100%;
    height: 100%;
    position: absolute;
    backface-visibility: hidden;
    transition: transform 0.5s ease;
}
.card .back 
{
    transform: rotateY(180deg);
}

.card.flipped .front 
{
    transform: rotateY(180deg);
}

.card.flipped .back 
{
    transform: rotateY(0deg);
}

.hidden 
{
    background-image: url('');
}

.visible
{
    background-color: white;
}

#idle-screen,
#win-screen,
#lose-screen 
{
    width: 100vw;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    position: absolute;
    top: 0;
    left: 0;
}

#idle-screen img,
#win-screen img,
#lose-screen img 
{
    max-width: 100%;
    max-height: 100%;
}