html {
  font-size: 50%;
}
.calc {
  border: 1px solid #ccc;
height: 350px;
  width: 300px;
}
button{
  height: 60px;
  width: 60px;
  background-color: white;
  font-size:20


}
.d{
  background-color: black;
  width: 250px;
  height: 50px;
  font-size:30px;
  color: white;
  text-align: right;

}
.AC{
  background-color: red;
}
.uguale{
  background-color: #2e86c0;
   border-color: #337cac;
   color: #fff;
   /*height: 50%;*/


}