* {
    margin: 0;
    padding: 0;
    font-family: Arial, Helvetica, sans-serif;
    text-align: center;
    color: rgb(255, 255, 255);
    font-size: 30px;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    background-color: rgb(121, 251, 255);
}

.outer-div {
    background-color: rgb(172, 220, 221);
    height: 800px;
    width: 450px;
    margin: 100px auto 0px auto;
    display:flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    row-gap: 10px;
}

h1 {
    display: inline-block;
    margin-top: 20px;
    width: 100%;
    background-color: rgb(28, 57, 66);
}

.calculator {
    width: 90%;
    flex:0.95;
    background-color: black;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    border-radius: 50px;
    border: 5px solid rgb(166, 166, 166);
    overflow: hidden;
}

.screen {
    height: 30%;
    width: 100%;
    position: relative;
}

.output {
    position: absolute;
    right: 20px;
    bottom: 0;
    font-size:50px;
    font-family: 'Franklin Gothic Medium', 'Arial Narrow', Arial, sans-serif;
    overflow-wrap: anywhere;
    user-select: none;
}

.keypad {
    flex: 1;
    width: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    row-gap: 10px;
}

.row {
    width: 100%;
    display: flex;
    justify-content:space-evenly;
    align-items: center;
}
button {
    background-color: #333333;
    height: 85px;
    width: 85px;
    border-radius: 50%;
    border: none;
    cursor: pointer;
}

button:active {
    background-color: rgb(37, 37, 37);
}

.operator{
    background-color: #ff9f0a;
}
.operator:active {
background-color: #da8405;
}

.output-buttons {
    background-color: #727272;
}
.output-buttons:active {
    background-color: #919191;
}
@media screen and (max-width: 430px){
    .outer-div {
        height: 200%;
        width: 100%;
        margin: 0;
    }
    .screen{
        height: 200px;
    }
    .calculator{
        align-self:flex-start;
        width: 100vw;
    }
    .keypad {
        padding-bottom: 40px;
    }
}