* {
    padding: 0;
    margin: 0;
    box-sizing: border-box;
}
main {
    position: relative;
    margin: 100px;
}
table {
    border-collapse: collapse;
}
table td {
    width: 50px;
    height: 50px;
    border: 1px solid #000;
}
#x-axis {
    position: absolute;
    top: -40px;
}
#x-axis span {
    display: inline-block;
    float: left;
    width: 50px;
    height: 30px;
    text-align: center;
}

#y-axis {
    position: absolute;
    left: -55px;
    top: 15px;
    width: 50px;
}
#y-axis span {
    display: inline-block;
    float: left;
    width: 50px;
    height: 50px;
    text-align: center;
}
#move {
    display: inline-block;
    position: absolute;
    top: 1px;
    left: 1px;
    width: 49px;
    height: 49px;
    border-bottom: 10px solid #266fff;
    background-color: #ff3b5b;
}
#square {
    margin-top: 20px;
}
input {
    width: 306px;
    margin-bottom: 10px;
}