* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Helvetica;
    color: grey;
}

html, body {
    height: 100%;
}

.main-container {
    width: 100vw;
    height: 100%;
    background-color: #675673;
    display: flex;
    align-items: center;
}

.calculator {
    width: 30vw;
    height: 90vh;
    background-color: #689B8A;
    border: 2px solid #66b0ab;
    border-radius: 20px;
    margin: auto;
    padding: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
}

.calculator-display {
    width: 28vw;
    height: 15vh;
    border: 2px solid #66b0ab;
    border-radius: 20px;
    background-color: #78B9B5;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    padding: 10px;
}

.display-equation {
    font-size: 30px;
}

.calculator-buttons {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

.number-button, .operator-button, .equal-button, .clear-button, .delete-button, .decimal-button, .negative-button {
    background-color: #78B9B5;
    width: 13vh;
    height: 13vh;
    border: 2px solid #66b0ab;
    border-radius: 20px;
    font-size: 25px;
}