body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    background-color: #f0f2f5;
}

.container { text-align: center; width: 90%; max-width: 600px; }

/* Styles de la carte */
.card {
    height: 300px;
    perspective: 1000px;
    cursor: pointer;
    margin-bottom: 20px;
}

.card-inner {
    position: relative;
    width: 100%;
    height: 100%;
    text-align: center;
    transition: transform 0.6s;
    transform-style: preserve-3d;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    border-radius: 15px;
}

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

.front, .back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    box-sizing: border-box;
    font-size: 1.2rem;
    border-radius: 15px;
    background: white;
}

.back {
    background-color: #3498db;
    color: white;
    transform: rotateY(180deg);
}

.controls { display: flex; justify-content: space-between; align-items: center; }
button {
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    background: #2c3e50;
    color: white;
    cursor: pointer;
}