* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    background-color: #f0f0f0;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.container {
    width: 90%;
    max-width: 800px;
    margin: 20px auto;
}

.controls-top {
    text-align: center;
    margin-bottom: 20px;
}

.controls-top button {
    margin: 0 10px;
}

.flashcard {
    perspective: 1000px;
    height: 400px;
    cursor: pointer;
    margin: 20px 0;
}

.front, .back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    background: white;
    border-radius: 10px;
    padding: 20px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    overflow-y: auto;
}

.back {
    transform: rotateY(180deg);
}

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

.flashcard.flipped .back {
    transform: rotateY(360deg);
}

.front, .back {
    transition: transform 0.6s;
    transform-style: preserve-3d;
}

.front h3, .back h3 {
    color: #333;
    margin-bottom: 20px;
    text-align: center;
}

.front p, .back p {
    font-size: 16px;
    line-height: 1.6;
    margin-bottom: 20px;
}

.metadata {
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid #eee;
}

.controls-bottom {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 20px;
    margin-top: 20px;
}

button {
    padding: 10px 20px;
    background-color: #0070d2;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
}

button:hover {
    background-color: #005fb2;
}

button:disabled {
    background-color: #c9c9c9;
    cursor: not-allowed;
}

#cardCount {
    font-size: 16px;
    color: #666;
}

.metadata a {
    color: #0070d2;
    text-decoration: none;
}

.metadata a:hover {
    text-decoration: underline;
}