@import url('https://fonts.googleapis.com/css2?family=Fredoka:wght@300..700&display=swap');

*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Fredoka", sans-serif;

    font-optical-sizing: auto;
    font-weight: 400;
    font-style: normal;
    font-variation-settings: "wdth" 100;
    color: var(--black);
}

:root{
    --bege-retro: #fcf6e6;
    --black: #2f352d;
    --highlight1: #6bb593;
}

body{
    background: rgb(107,181,147);
    background: radial-gradient(circle, rgba(107,181,147,1) 0%, rgba(252,246,230,1) 100%);
}

.app{
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

.calculator{
    background-color: var(--bege-retro);
    width: 100%;
    max-width: 375px;
    min-height: 640px;
    display: flex;
    flex-direction: column;
    border-radius: 1.5rem;
    overflow: hidden;
    box-shadow: 8px 8px 0px 0px var(--black);
    border: 4px solid var(--black);
}

.display{
    min-height: 200px;
    padding: 1.5rem;
    display: flex;
    justify-content: flex-end;
    align-items: flex-end;
    flex: 1 1 0%;
}

.display .input{
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
}

.display .output{
    width: 100%;
    max-width: 100%;
    overflow: auto;
    font-size: 3rem;
    font-weight: 500;
}

.display .operator,
.display .brackets,
.display .percent{
    color: var(--highlight1);
}

.btns{
    background-color: var(--highlight1);
    padding: 1.5rem;
    border-radius: 1.5rem 1.5rem 0 0;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-template-rows: repeat(5, 1fr);
    grid-gap: 1rem;
}

.btns .btn{
    position: relative;
    height: 0;
    padding-top: 100%;
    background-color: var(--bege-retro);
    border-radius: 1rem;
    transition: 0.2s;
    user-select: none;
    box-shadow: 4px 4px 0px 0px var(--black);
}

.btns .btn span{
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 1.5rem;
}

.btns .btn:active{
    box-shadow: inset 0 0 3px var(--black);
}