style.css

body{
    display:flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height:90vh;
    font-family:monospace;
}
.grid{
    width: 300px;
    height: 300px;
    border: solid black 1px;
    display: flex;
    flex-wrap: wrap;
}

.grid div{
    height:20px;
    width:20px;
}

.invader{
    background-color: purple;
    border-radius:50%;
}
.shooter{
    background-color: green;
}

.laser{
    background-color:orange;
}

.alienLaser{
    background-color:red;
}

.boom{
    background-color:rgb(255, 94, 0);
}
.instructions{
    margin-top: 50px;
    font-size: larger;
    font-weight: bold;
}

#levels{
    display: flex;
    margin: 40px 0;
}

#levels button{
    /* margin: 0 10px;
    background: orange;
    border: 5px solid blue;
    box-shadow: 5px 5px 5px blue; */
    margin:0 10px;
}