body {
    font-family: 'Courier New', Courier, monospace;
    background-color: #1a1a1a;
    color: #f2f2f2;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    padding: 0;
}

#timer {
    text-align: center;
    border: 2px solid #4CAF50;
    padding: 20px;
    border-radius: 15px;
    background: rgba(0, 0, 0, 0.8);
    box-shadow: 0 0 20px #4CAF50;
    width: 80%;
    max-width: 500px;
}

#time-display {
    font-size: 5em;
    color: #4CAF50;
    margin-bottom: 0.3em;
    text-shadow: 0 0 10px #4CAF50;
}

#round-display {
    font-size: 1.5em;
    margin-bottom: 1em;
    color: #f2f2f2;
}

button {
    background-color: #333;
    color: #f2f2f2;
    border: none;
    padding: 10px 20px;
    margin: 10px;
    border-radius: 5px;
    font-size: 1em;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.3s;
}

button:hover {
    background-color: #4CAF50;
    transform: scale(1.1);
}

button:active {
    transform: scale(0.9);
}

button:focus {
    outline: none;
}

/* Media query for tablets */
@media (max-width: 768px) {
    #time-display {
        font-size: 3em;
    }

    #round-display {
        font-size: 1.2em;
    }

    button {
        font-size: 0.8em;
        padding: 8px 16px;
    }
}

/* Media query for smaller mobile devices */
@media (max-width: 480px) {
    #time-display {
        font-size: 2em;
    }

    #round-display {
        font-size: 1em;
    }

    button {
        font-size: 0.7em;
        padding: 6px 12px;
    }
}