body{
text-align: center;
}

h1{
  text-align: center;


}

.center {
  margin: auto;
  width: 50%;
  border: 3px solid green;
  padding: 10px;
}
.canvas{
  border: 1px dotted green;
  margin: 15px auto 15px auto;
}
button{
  margin: 10px;
}
input{
  width: 40px;
}
.goGreen{
  background-color: green;
}
.goRed{
  background-color: red;
}