body {
    font-family: 'Poppins', sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    background-color: #f0f4f8;
    color: #2c3e50;
}

#game-container {
    background-color: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
    text-align: center;
    max-width: 450px;
    width: 90%;
}

h1 {
    color: #3498db;
    margin-bottom: 20px;
}

#status-area {
    font-size: 1.2em;
    font-weight: 600;
    margin-bottom: 20px;
}

/* --- Timer Bar --- */
#timer-bar-container {
    width: 100%;
    height: 15px;
    background-color: #ecf0f1;
    border-radius: 8px;
    margin-bottom: 25px;
    overflow: hidden;
}

#timer-bar {
    height: 100%;
    width: 100%; /* Starts full */
    background-color: #2ecc71; /* Green */
    transition: width linear; /* Smooth transition */
}

/* --- Problem Display --- */
#problem-box {
    background-color: #34495e; /* Dark background */
    color: white;
    padding: 20px 10px;
    border-radius: 8px;
    margin-bottom: 25px;
}

#problem-display {
    font-size: 2.5em;
    font-weight: bold;
    margin: 0;
}

/* --- Options Container --- */
#options-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    margin-bottom: 25px;
}

.answer-button {
    padding: 15px 10px;
    font-size: 1.3em;
    font-weight: bold;
    background-color: #f1c40f; /* Yellow */
    color: #333;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.1s, transform 0.1s;
}

.answer-button:hover:not(:disabled) {
    background-color: #f39c12;
    transform: translateY(-2px);
}

.answer-button:disabled {
    cursor: not-allowed;
    opacity: 0.7;
}

/* Feedback Styles */
.correct {
    background-color: #2ecc71 !important; /* Green */
    color: white;
}

.incorrect {
    background-color: #e74c3c !important; /* Red */
    color: white;
}

/* --- Controls --- */
#feedback-message {
    min-height: 1.5em;
    font-weight: bold;
    margin-bottom: 15px;
}

#start-button {
    padding: 12px 25px;
    font-size: 1.2em;
    font-weight: bold;
    background-color: #3498db;
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.2s;
}

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