#calcModal{
  position:fixed;
  top:0; left:0; right:0; bottom:0;
  background:rgba(0,0,0,.4);
  display:flex;
  align-items:center;
  justify-content:center;
  z-index:9999;
}
.calc-box{
  background:#fff;
  padding:15px;
  border-radius:8px;
  width:220px;
}
.calc-box input{
  width:100%;
  font-size:20px;
  text-align:right;
  margin-bottom:10px;
}
.calc-keys button{
  width:23%;
  margin:2px;
}
.calc-actions{
  margin-top:10px;
  text-align:right;
}