*, *::before, *::after {
    box-sizing: border-box;
    font-family: Arial, Helvetica, sans-serif;
}

:root {
    color-scheme: dark;
}

body {
    background-color: #333;
    color: #fff;
    font-size: 1.1rem;
    min-height: 100vh;
    margin: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

div {
    text-align: center;
}

input, select, button {
    padding: .5em 1em;
    font-size: inherit;
    color: inherit;
    border-radius: 5px;
    outline: none;
    transition: background-color 150ms ease-in-out, border-color 250ms ease-in-out;
}

input, select {
    background-color: #2b2a33;
    border: 3px solid #666;
}

input:hover, input:focus, select:hover, select:focus-visible {
    background-color: #18171c;
}

button {
    background-color: #316b2c;
    border: 2px solid #316b2c;
    cursor: pointer;
}

button:hover, button:focus-visible {
    background-color: #2c6b58;
    border-color: #444;
}

#output {
    font-size: 2em;
    opacity: 1;
    transition: opacity 500ms ease-in-out;
}

@media screen and (max-width: 37.5em) {
    body {
        font-size: 1rem;
    }
}

@media screen and (max-width: 18.75em) {
    body {
        font-size: 0.75rem;
    }
}