/* Reset & Base Styles */
    * {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
    }
    body {
        font-family: 'Segoe UI', sans-serif;
        background-color: #1e1e2f;
        color: #fff;
        display: flex;
        flex-direction: column;
        align-items: center;
        min-height: 100vh;
        padding: 2rem;
        transition: background-color 0.3s ease;
    }
    
    header {
        text-align: center;
        margin-bottom: 2rem;
    }
    
    h1 {
        font-size: 2.5rem;
        margin-bottom: 0.5rem;
    }
    
    p {
        font-size: 1.1rem;
        opacity: 0.8;
    }
    
    footer {
        margin-top: auto;
        padding-top: 2rem;
        font-size: 0.9rem;
        opacity: 0.6;
    }
    
    /* Game Container */
    .game-container {
        width: 100%;
        max-width: 400px;
        display: flex;
        flex-direction: column;
        gap: 2rem;
    }

    /* Instructions Button */
    .btn-how-to-play {
        padding: 0.5rem 1rem;
        font-size: 1rem;
        cursor: pointer;
        background-color: #4CAF50;
        color: white;
        border: none;
        border-radius: 5px;
        transition: background-color 0.2s;
    }
    
    .btn-how-to-play:hover {
        background-color: #3e8e41;
    }
    
    /* Game Board */
    #level-display {
        text-align: center;
        font-size: 1.2rem;
        margin-bottom: 1rem;
        min-height: 1.5rem;
        font-weight: bold;
    }
    
    .grid {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: 1rem;
        margin-bottom: 1rem;
    }
    
    .tile {
        width: 150px;
        height: 150px;
        border: none;
        border-radius: 20%;
        opacity: 0.7;
        transition: transform 0.2s, opacity 0.2s, box-shadow 0.2s;
        cursor: pointer;
    }
    
    .tile:disabled {
        cursor: not-allowed;
        opacity: 0.5;
    }
    
    .green { background-color: #60bd68; }
    .red { background-color: #ff5b5b; }
    .yellow { background-color: #ffee33; }
    .blue { background-color: #42aaf5; }
    
    .tile.pressed {
        transform: scale(0.95);
        opacity: 1;
        box-shadow: 0 0 15px rgba(255, 255, 255, 0.8);
    }
    
    /* Start Button */
    #btn-start {
        display: block;
        margin: 0 auto;
        padding: 0.75rem 1.5rem;
        font-size: 1rem;
        background-color: #333;
        color: white;
        border: none;
        border-radius: 5px;
        cursor: pointer;
        transition: background-color 0.2s;
    }
    
    #btn-start:hover {
        background-color: #555;
    }
     /* i used Deepseek to optimize Displaying the content of the instructions */
    /* Modal */
    .modal {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background-color: rgba(0, 0, 0, 0.8);
        display: flex;
        justify-content: center;
        align-items: center;
        z-index: 1000;
    }
    
    .modal.hidden {
        display: none;
    }
    
    .modal-content {
        background-color: #2c2c3d;
        padding: 2rem;
        border-radius: 10px;
        position: relative;
        max-width: 300px;
        text-align: center;
    }
    
    .modal-content h2 {
        margin-bottom: 1rem;
    }
    
    .modal-content ol {
        text-align: left;
        margin-left: 1rem;
        line-height: 1.6;
    }
    
    .modal-content li {
        margin-bottom: 0.5rem;
    }
    
    .close-modal {
        position: absolute;
        top: 10px;
        right: 15px;
        font-size: 1.5rem;
        cursor: pointer;
        transition: color 0.2s;
    }
    
    .close-modal:hover {
        color: #ff5b5b;
    }
    /* here is the end of the instruction section */
    /* Game Over State */
    .game-over {
        background-color: #ff4d4d;
    }
    
    /* Status Messages */
    .status-message {
        text-align: center;
        font-size: 1rem;
        min-height: 1.5rem;
        margin-bottom: 1rem;
        opacity: 0.8;
    }
    
    /* Responsive */
    @media (max-width: 480px) {
        .tile {
            width: 120px;
            height: 120px;
        }
    
        #level-display {
            font-size: 1rem;
        }
    
        h1 {
            font-size: 2rem;
        }
    }