body {
    font-family: Arial, sans-serif;
    margin: 20px;
}

nav a {
    margin-right: 10px;
    text-decoration: none;
    color: blue;
}

nav a:hover {
    text-decoration: underline;

}

#sim-area {
    position: relative;
    width: 400px;
    height: 200px;
    margin: 20px auto;
    border: 2px solid #000;
    background-image: 
    linear-gradient(0deg, transparent 24%, #ddd 25%, #ddd 26%, transparent 27%),
    linear-gradient(90deg, transparent 24%, #ddd 25%, #ddd 26%, transparent 27%);
    background-size: 20px 20px;
    overflow: hidden;
}

#axis-x, #axis-y {
    position: absolute;
    background: blue;
}

#axis-x {
    top: 50%;
    left: 0;
    width: 100%;
    height: 2px;
}

#axis-y {
    left: 50%;
    top: 0;
    width: 2px;
    height: 100%;
}

.box {
    width: 20px;
    height: 20px;
    background: red;
    border-radius: 50%;
    position: absolute;
    left: 190px;
    top: 190px;
    cursor: grab;
    /* transition: left 0.3s; */
}

#coords {
    text-align: center;
    font-size: 1.2em;
    margin-top: 10px;
}