@import url('https://fonts.googleapis.com/css?family=Space+Mono');

/* quick reset so all our padding is the right size */
* {
  box-sizing: border-box;
}

.calculator{
    max-width:320px;
    background: #eee;
}
.calculator-buttons{
    display:grid;
    grid-template-columns: repeat(4,1fr);
    border:0;
}
.calc-numbers{
    font-family: 'Space Mono', serif;
    background: black;
    color: white;
    font-size: 2em;
    border:0;
    padding: 0.3em;
    text-align: right;
    width: 100%;
    height: 100px;
}
.span-2{
    grid-column: span 2;
}
.span-3{
    grid-column: span 3;
}
.btn{
    font-size:1em;
    height: 65px;
    border:1px solid black;
}
.btn:hover{
    background: #fff;
}
.orange{
    background-color:orange;
}