body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    font-family: Arial, sans-serif;
    background-color: #f4f4f9;
}

.container {
    text-align: center;
    background-color: #fff;
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0px 4px 10px rgba(0, 0, 0, 0.1);
}

h1 {
    font-size: 2rem;
    color: #333;
}

.coin {
    width: 120px;
    height: 120px;
    background-color: #f1c40f;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
    color: #333;
    margin: 20px auto;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    position: relative;
    transform-style: preserve-3d;
}

.coin div {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 50%;
}

.heads {
    background-color: #f1c40f;
    transform: rotateY(0deg);
}

.tails {
    background-color: #b0b0b0;
    transform: rotateY(180deg);
}

.flip {
    animation: flip 1s ease-out;
}

@keyframes flip {
    0% { transform: rotateY(0deg); }
    50% { transform: rotateY(720deg); }
    100% { transform: rotateY(720deg); }
}

button {
    padding: 10px 20px;
    font-size: 1.2rem;
    background-color: #3498db;
    color: #fff;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

button:hover {
    background-color: #2980b9;
}