styles.css

@import url('https://fonts.googleapis.com/css?family=Roboto:300,400,500,700,900&display=swap');

html {
    height: 100vh;
}

body {
    font-family: 'Roboto', sans-serif;
    max-width: 700px;
    margin: auto;
    background-image: url("dan-gold-E6HjQaB7UEA-unsplash.jpg");
    background-size: 100%;
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: center;
    height: 100vh;
    background-position: center center;
    background-size: cover;
}


.calculator-container {
    background-color: rgb(155, 168, 159, 0.7);
    height: 400px;
    width: 400px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    border-radius: 20px;
}

.data-for-calculator{
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 0px 50px 10px 50px;
}

.data-for-calculator input {
    margin: 10px;
    display: flex;
    text-align: center;
    font-family: 'Roboto', sans-serif;
    font-size: 18px;
    border: 1px solid #7a8388;
    box-shadow: 2px 2px 2px 0px rgba(0,0,0,0.31);
}

.title h1 {
    display: flex;
    justify-content: center;
    font-size: 40px;
    font-weight: 500;
    color: #ecae35;
}

h1 {
    margin: 0 10px 10px 10px;
}

.button-flex {
    display: flex;
    flex-direction: row;
    justify-content: center;
}

#calculate-button, #reset-button {
    margin: 0 15px 10px 20px;
    font-family: 'Roboto', sans-serif;
    font-size: 20px;
    background-color: #fabc2b;
    color: #ffffff;
    border: none;
    border-radius: 10px;
}

#reset-button {
    padding: 3px 20px;
}

.calculate-result {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 0 50px 0 50px;
}

.calculate-result p {
    margin: 5px 0;
    color: #ffffff;
    font-size: 20px;
    font-weight: bold;
}

.result {
    display: flex;
    flex-direction: row;
}

.result > p:first-child {
    margin-right: 10px;
}

.result > p:last-child {
    font-size: 20px;
}

@media (max-width: 1000px) {
    body {
        background-image: url("dan-gold-E6HjQaB7UEA-unsplash_vertical.jpg");
        background-repeat: no-repeat;
    }
}