:root {
    --hi-color: purple;
    --fg-color: lightgrey;
    --bg-color: white;
}

body {
    background-color: var(--bg-color);
    animation-name: fadein;
    animation-duration: 1s;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
}

#game {
    display: flex;
    flex-direction: row;
}

div.vertex {
    padding: 1em;
    background-color: var(--hi-color);
    border-radius: 50%;
}

div.vertex.off {
    background-color: var(--fg-color);
}

section#optionsScreen {
    display: flex;
    flex-direction: column;
    /* align-items: center; */
    justify-content: space-between;
}

section.screen {
    animation: fadein 1s linear;
}

section.screen.inactive {
    display: none;
}

button {
    background-color: var(--hi-color);
    color: var(--fg-color);
    padding: 2em 3em;
    border: none;
}

button:hover {
    filter: brightness(120%);
}

button:focus {
    outline: none;
}

@keyframes fadein {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}