@import url('https://fonts.googleapis.com/css2?family=Concert+One&display=swap');
@import url('https://fonts.googleapis.com/css2?family=Righteous&display=swap');

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

html,
body {
    height: 100%;
    background-color: #f2675b;
}

a { text-decoration: none; }

.container {
    padding: 100px;
}

.calc-body {
    position: relative;
    width: 400px;
    min-height: 510px;
    margin: auto;
    background-color: #4b4b4b;
    border-radius: 50px;
    box-shadow: inset 13px 8px 0px 5px #2b2b2b;
    padding-left: 20px;
    z-index: 2;
}

.calc-body-shadow {
    position: relative;
    bottom: 224px;
    left: 540px ;
    width: 400px;
    height: 200px;
    background-color: #b8574f;
    border-radius: 50px;
    transform: skew(50deg, -7deg);
    z-index: 1;
}

.calc-screen {
    padding: 50px 25px 30px 30px;
    text-align: center;
    min-height: 100px;
}

.calc-operation {
    width: 320px;
    min-height: 80px;
    background-color: #b5c3b3;
    padding: 10px 26px 0;
    font-size: 50px;
    font-family: 'Concert One', cursive;
    color: #1b263b;
    text-align: right;
    box-shadow:
        inset 0px -8px 0px -3px #939e94,
        inset -7px 0px 0px 0px #6a726b;
}

.calc-history {
    width: 320px;
    height: 39px;
    background-color: #b5c3b3;
    padding: 20px 26px 0;
    font-size: 16px;
    font-family: 'Concert One', cursive;
    color: #646c7a;
    text-align: right;
    box-shadow: inset -7px 0px 0px 0px #6a726b;
}

.calc-buttons {
    display: grid; 
    grid-template-columns: 1fr 1fr 1fr 1fr; 
    grid-template-rows: 1fr 1fr 1fr 1fr 1fr; 
    gap: 10px 10px; 
    grid-template-areas: 
      ". . . ."
      ". . . ."
      ". . . ."
      ". . . ."
      ". . equals equals";
    padding: 0 40px;
}

.equals {
    grid-area: equals; 
    background-color: #dca86e;
    box-shadow: -4px -2px 0px 1px #aa8156;
}

.equals:active {
    box-shadow: -2px -2px 0px 1px #aa8156;
}

button {
    height: 45px;
    background-color: #cdcdcd;
    font-family: 'Righteous', cursive;
    font-size: 18px;
    color: #575757;
    border: 0;
    outline: 0;
    border-radius: 10px;
    cursor: pointer;
    box-shadow: -4px -2px 0px 1px #9d9d9d;
}

button:active {
    transform: translateX(-2px);
    box-shadow: -2px -2px 0px 1px #9d9d9d;
}

.red-btn {
    background-color: #de524b;
    color: #E0E0E0;
    box-shadow: -4px -2px 0px 1px #a93f3a;
}

.red-btn:active {
    box-shadow: -2px -2px 0px 1px #a93f3a;
}