@font-face {
    font-family: 'DS-Digital-Bold';
    src: url('./fonts/DS-DIGIB.TTF');
}

:root {
    --calc-container: #333;
    --calc-display: #ccc;
}

* {
    margin: 0;
    padding: 0;
}

h1,
button {
    font-family: 'DS-Digital-Bold';

}

main {
    max-width: 100vw;
    min-height: 100vh;
    position: absolute;
    display: inline-flex;
    left: 50%;
    transform: translateX(-50%);
    align-items: center;
}

#calc-container {
    position: relative;
    background-color: var(--calc-container);
    max-width: 100%;
    width: 400px;
    height: 600px;
    max-height: 100%;
    border-radius: 2rem;
}

#calc-display {
    position: absolute;
    display: flex;
    align-items: center;
    margin: 10% 5%;
    padding: 0 5%;
    background-color: var(--calc-display);
    width: 80%;
    height: 10%;
    border-radius: 1rem;

}

#buttons {
    position: absolute;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-template-rows: repeat(5, 1fr);
    width: 90%;
    height: 60%;
    bottom: 5%;
    text-align: center;
    margin-left: 50%;
    transform: translateX(-50%);
}

.btn-calc {
    position: relative;
    margin: .2rem;
    width: 90%;
    height: 3rem;
    font-size: 30px;
}

#equal {
    height: 7.5rem;
    grid-column-start: 4;
    grid-row-start: 4;
    grid-row-end: 6;
}

#zero {
    width: 95%;
    grid-column-start: 1;
    grid-column-end: 3;
    grid-row-start: 5;
}

.btn-calc span {
    position: absolute;
    font-size: 15px;
}