Calculator.css

button {
   display: inline-block;
   padding: 15px 25px;
   font-size: 24px;
   cursor: pointer;
   text-align: center;
   text-decoration: none;
   outline: none;
   color: #fff;
   background-color: #C52233;
   border: none;
   border-radius: 15px;
   box-shadow: 0 9px #999;
}
button:hover {
    background-color: #802731
}

button:active {
   background-color: #C52233;
   box-shadow: 0 5px #666;
   transform: translateY(4px);
}

input[type=text] {
    display: inline-block;
    -webkit-box-sizing: content-box;
    -moz-box-sizing: content-box;
    box-sizing: content-box;
    padding: 10px 0px;
    border: 1px solid #b7b7b7;
    -webkit-border-radius: 3px;
    border-radius: 3px;
    font: normal 20px/normal "baumans", Helvetica, sans-serif;
    color: rgba(255,255,255,1);
    -o-text-overflow: clip;
    text-overflow: clip;
    background: #c52233;
    -webkit-box-shadow: 2px 2px 2px 0 rgba(0,0,0,0.2) inset;
    box-shadow: 2px 2px 2px 0 rgba(0,0,0,0.2) inset;
    text-shadow: 1px 1px 0 rgba(43,5,12,0.66) ;
    -webkit-transition: all 200ms cubic-bezier(0.42, 0, 0.58, 1);
    -moz-transition: all 200ms cubic-bezier(0.42, 0, 0.58, 1);
    -o-transition: all 200ms cubic-bezier(0.42, 0, 0.58, 1);
    transition: all 200ms cubic-bezier(0.42, 0, 0.58, 1);
}