body {
    font-family: Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background-color: #121212;
    margin: 0;
    color: #FFFFFF;
}

.captcha-container {
    background-color: #1E1E1E;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
    text-align: center;
    width: 300px;
    position: relative;
}

.emoji-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    margin: 20px 0;
}

.emoji {
    font-size: 2rem;
    cursor: pointer;
    transition: transform 0.2s;
}

.emoji:hover {
    transform: scale(1.2);
}

.emoji.selected {
    border: 2px solid #007BFF;
    border-radius: 8px;
    transform: scale(1.2);
}

#verify-button {
    padding: 10px 20px;
    font-size: 1rem;
    cursor: pointer;
    background-color: #007BFF;
    border: none;
    color: #FFF;
    border-radius: 5px;
}

#verify-button:disabled {
    background-color: #555;
}

#result-message {
    margin-top: 10px;
    font-weight: bold;
}

.hidden {
    display: none;
}

#error-message {
    color: red;
    font-weight: bold;
    margin-top: 10px;
}

.difficulty-selector {
    margin-top: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.difficulty-selector label {
    margin-right: 10px;
}

.emoji.correct {
    animation: correctAnimation 0.5s ease-in-out;
}

.emoji.wrong {
    animation: wrongAnimation 0.5s ease-in-out;
}

@keyframes correctAnimation {
    0% { background-color: #4CAF50; }
    100% { background-color: transparent; }
}

@keyframes wrongAnimation {
    0% { background-color: #F44336; }
    100% { background-color: transparent; }
}