@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@100;300;500;600&display=swap');

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Poppins', sans-serif;
    letter-spacing: 1px;
}

main {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100vw;
    height: 100vh;
    background-image: linear-gradient(140deg, #00ec00, #0a66c2);
}

.calculadora {
    position: relative;
    padding: 20px;
    min-width: 400px;
    max-width: 90vw;
    background: #121214;
    border-radius: 20px;
    box-shadow: 0px 0px 6px 2px rgba(0, 0, 0, 0.5);
}

.display-box {
    position: relative;
    display: flex;
    justify-content: right;
    align-items: center;
    width: 100%;
    height: 15%;
    padding: 10px 15px;
    border-radius: 10px;
    color: #fff;
    font-size: 4rem;
    background: #222;
    box-shadow: inset 0px 0px 4px 4px rgba(0, 0, 0, 0.2);
}

#display {
    overflow: hidden;
    white-space: nowrap;
}

.btn-box {
    position: relative;
    padding: 12px 8px 0 0;
    width: 100%;
    height: 85%;
}

.btn {
    cursor: pointer;
    position: relative;
    width: 100%;
    height: 80px;
    margin: 4px;
    font-size: 150%;
    font-weight: 600;
    border: none;
    border-radius: 10px;
    color: #fff;
    background: #222;
    transition: 0.2s;
}

.btn:hover {
    background: #000;
}

.btn-igual {
    height: 94%;
}

@media (max-width: 768px) {
    .calculadora {
        min-width: 70vw !important;
        height: 90vw;
    }
    .display-box {
        font-size: 8vw;
    }
    .btn-box {
        position: relative;
        padding: 2% 3% 0 0;
        width: 100%;
        height: 85%;
    }
    .btn {
        cursor: pointer;
        position: relative;
        width: 100%;
        height: 80%;
        font-size: 150%;
        font-weight: 600;
        border: none;
        border-radius: 10px;
        color: #fff;
        background: #222;
        transition: 0.2s;
    }
    .btn-igual {
        height: 94%;
    }
}