_.css

<style>
    body,
    html {
        height: 100%;
    }

    #editor {
        height: 100%;
    }
    body > div:first-child {
        height: 70%;
        display: flex;
        flex-direction: column;
    }
    body > div:nth-child(2) {
        height: 30%;
        display: flex;
        flex-direction: column;
    }

    nav {
        font-family: "Ubuntu Mono", monospace;
        display: flex;
        justify-content: space-between;
        align-items: center;
    }

    #console {
        height: 100%;
        margin: 0;
        overflow-y: auto;
        font-family: "Ubuntu Mono", monospace;
    }
    [action] {
        cursor: pointer;
    }
    nav > span {
        display: block;
    }
</style>