body {
    font-family: 'Press Start 2P', cursive, monospace; /* Retro arcade font style */
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    background-color: #2c3e50; /* Dark blue background */
    color: #ecf0f1;
}

#game-container {
    background-color: #34495e;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.5);
    text-align: center;
    max-width: 450px;
    width: 90%;
}

h1 {
    color: #f1c40f; /* Yellow title */
    margin-bottom: 25px;
}

#status-area {
    font-size: 0.9em;
    font-weight: bold;
    margin-bottom: 30px;
    color: #bdc3c7;
}

/* --- Button Grid --- */
#button-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    width: 300px;
    height: 300px;
    margin: 0 auto;
    margin-bottom: 30px;
}

.game-button {
    height: 100%;
    font-size: 2.5em;
    font-weight: bold;
    border: 5px solid #2c3e50;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.1s ease-in;
    color: white;
}

/* Initial Colors (Simulated off-state) */
.game-button[data-id="1"] { background-color: #e74c3c; } /* Red */
.game-button[data-id="2"] { background-color: #2ecc71; } /* Green */
.game-button[data-id="3"] { background-color: #3498db; } /* Blue */
.game-button[data-id="4"] { background-color: #f39c12; } /* Orange */

/* --- The Active (Lit Up) State --- */
.game-button.active {
    /* Brighter version of the color */
    box-shadow: 0 0 25px 5px rgba(255, 255, 255, 0.8), 0 0 10px rgba(255, 255, 255, 0.5);
    transform: scale(1.05);
}

.game-button[data-id="1"].active { background-color: #ff6b6b; } 
.game-button[data-id="2"].active { background-color: #4cd964; }
.game-button[data-id="3"].active { background-color: #5d9cec; }
.game-button[data-id="4"].active { background-color: #ffae19; }

.game-button:disabled {
    cursor: not-allowed;
    opacity: 0.5;
}

/* --- Controls and Feedback --- */
#feedback-message {
    min-height: 20px;
    margin-bottom: 20px;
}

#start-button {
    padding: 12px 25px;
    font-size: 1.1em;
    font-weight: bold;
    background-color: #9b59b6; /* Purple */
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.2s;
}

#start-button:hover {
    background-color: #8e44ad;
}