*, *::before, *::after {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family:cursive;
    height: 100vh;
    font-size: 1.5rem;
    display: flex;
    flex-direction: column;
    background-image: linear-gradient(rgb(103, 103, 103), black);
}

.heading {
    font-size: 2rem;
    color: rgb(255, 183, 183);
    font-family: "Bungee Spice", sans-serif;
    font-weight: 400;
    text-align: center;
    text-shadow: 5px 5px 6px rgb(43, 43, 43);
}

.calculator-body {
    border: 6px solid rgb(52, 52, 52);
    background-image: linear-gradient(rgb(37, 37, 37), rgb(68, 68, 68));
    padding: 16px 8px;
    margin: 0 auto;
    color: rgb(255, 202, 202);
    box-shadow: 10px 10px 5px rgba(0, 0, 0, 50%);
}

.display {
    padding: 0 .3em;
    border: 6px solid rgb(52, 52, 52);
    background-color: rgb(191, 255, 64);
    color: black;
    font-size: 1.7rem;
    margin: 0 10px;
    height: 3em;
    display: flex;
    align-items:center;
    justify-content: flex-end;
}

.calculator-buttons {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    margin-top: 10px;
    gap: 11px;
}

.btn {
    width: 3.5em;
    height: 3.5em;
    font-size: 1.2rem;
    border: 0px;
    border-radius: 100px;
}

.function-btn {
    background-color: rgb(255, 152, 27);
}

.number-btn {
    background-color: rgb(255, 183, 183);
}

.equals {
    background-color: rgb(255, 0, 0);
}

.btn:hover,
.btn.focus {
    background-color: rgb(90, 0, 0);
    color: white;
    transition: .8s;
}