body {
    margin: 0;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    font-family: 'Press Start 2P', cursive;
    text-rendering: optimizeLegibility;
    overflow: hidden;
    color: #00ffff;
}

#background-svg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
}

#game-container {
    background-color: rgba(0, 0, 0, 0.7);
    padding: 30px;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 10px 25px rgba(255,255,255,0.2);
    color: #00ffff;
    border: 3px solid #00ffff;
    position: relative;
    z-index: 10;
}

h1 {
    text-transform: uppercase;
    letter-spacing: 3px;
    text-shadow: 2px 2px 4px #00ffff;
    color: #00ffff;
}

.number-box {
    display: inline-block;
    width: 80px;
    height: 60px;
    margin: 10px;
    background-color: #001a33;
    color: #00ffff;
    line-height: 60px;
    font-size: 24px;
    border-radius: 5px;
    cursor: pointer;
    transition: transform 0.3s, box-shadow 0.3s;
    border: 2px solid #00ffff;
}

.number-box:hover {
    transform: scale(1.1);
    box-shadow: 0 0 15px #00ffff;
}

.number-box.selected {
    background-color: #003366;
    box-shadow: 0 0 10px #00ffff;
}

#checkButton, #resetButton {
    margin: 10px;
    padding: 10px 20px;
    background-color: #001a33;
    color: #00ffff;
    border: 2px solid #00ffff;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s;
    font-family: 'Press Start 2P', cursive;
    text-transform: uppercase;
}

#checkButton:hover, #resetButton:hover {
    background-color: #003366;
    box-shadow: 0 0 15px #00ffff;
    transform: scale(1.05);
}

#game-instructions {
    margin-bottom: 20px;
    font-style: italic;
    color: #00ffff;
    padding: 10px;
    background-color: rgba(0, 0, 0, 0.7);
    border-radius: 10px;
    border: 1px solid #00ffff;
}

#result-message {
    font-family: 'Press Start 2P', cursive;
    margin: 15px 0;
    text-transform: uppercase;
    color: #00ffff;
}