* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html,
body {
   width: 100%;
   height: 100%;
   margin: 0;
   padding: 0;
   font-family: "Trebuchet MS", Helvetica, sans-serif;
   font-size: 28px;
}
body {
   display: flex;
   justify-content: center;
   align-items: center;
   background-color: #f5f5f5;
}
.calculator {
   width: 350px;
   height: 500px;
   border-radius: 10px;
   box-shadow: 0 25px 60px -10px rgba(0,0,0,0.5);
   background-image: url("back.jpg");
   background-size: 160%;
   }
 

form {
  transform: rotateX(-30deg);
}
.container h1 {
  font-size: 60px;
  margin-top: -40%;
  color: beige;
  font-family: 'CursiveFont', cursive;
}

.calculator {
  background-color:33FFFA;
  
  border: 2px solid white;
}

.calculator form input {
  border: 0;
  outline: 0;
  width: 60px;
  height: 60px;
  border-radius: 10px;
  box-shadow: -8px -8px 15px rgb;
  cursor: pointer;
  margin: 10px;
}

form .display {
  display: flex;
  justify-content: flex-end;
  margin: 20px 0;
  
}

form .display input {
  text-align: right;
  flex: 1;
  font-size: 45px;
  box-shadow: none;
  border: 0;
  outline: 0;
  background: none;
  color: #1b1b1b; 
}
.row {
  display: flex;
}

.row input {
  border: 0;
  outline: 0;
  width: 60px;
  height: 60px;
  border-radius: 10px;
  box-shadow: -8px -8px 15px rgba(255, 255, 255, 0.1);
  cursor: pointer;
  margin: 10px;
  font-size: 20px;
  background-color: black;
  color: #fff;
  transition: background-color 0.3s ease;
}

.row input:hover {
  background-color:hsl(180, 63%, 32%);
}

.row input:active {
  background-color: hsl(180, 63%, 32%);
} 
@media only screen and (max-width: 800px) {
  .calculator {
    width: 130%; 
    max-width: none; 
  }

  .calculator form input,
  .row input {
    width: 30%; 
    max-width: none; 
    font-size: 16px; 
  }
}