body {
    font-family: sans-serif;
    background-color: #f4f4f9;
    color: #333;
    margin: 0;
    padding: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
}

header {
    width: 100%;
    max-width: 800px;
    background: white;
    padding: 1rem 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    margin-bottom: 20px;
}

#auth-container {
    display: flex;
    gap: 1rem;
    align-items: center;
}

main {
    width: 100%;
    max-width: 800px;
}

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

#shuffle-button {
    padding: 10px 20px;
    font-size: 1rem;
    color: white;
    background-color: #5a67d8;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s;
}

#shuffle-button:hover {
    background-color: #434190;
}

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

#seat-chart-container {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

#seat-chart {
    position: relative;
    width: 100%;
    height: 400px; /* Adjust as needed */
    border: 1px solid #ddd;
    border-radius: 5px;
    margin-top: 1rem;
    background-color: #fafafa;
}

.seat {
    position: absolute;
    width: 80px;
    height: 50px;
    border: 1px solid #aaa;
    border-radius: 4px;
    background: #e0e0e0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    font-size: 0.8rem;
    padding: 4px;
    box-sizing: border-box;
}

.seat .seat-id {
    font-weight: bold;
    color: #555;
}

.seat .student-name {
    color: #0056b3;
}