js/app-homepage/iframe/app.css

:root {
    --background-color: #18191b;
}

body {
    background-color: var(--background-color);
    color: var(--text-color);
    font-family: var(--font-family);
}

#container {
    display: flex;
    flex-direction: column;
}

h1 {
    margin-bottom: 20px;
    align-self: flex-start;
}

li {
    margin-bottom: 4px;
}

#teammate-list {
    display: flex;
    flex-direction: column;
    align-items: stretch;
}

#authorize-button {
    align-self: center;

    background-color: var(--ui-control-fill-color);
    color: white;

    height: 32px;

    border: 1px solid transparent;
    border-radius: 4px;
    box-shadow: rgba(255, 255, 255, .4) 0 1px 0 0 inset;
    box-sizing: border-box;
    cursor: pointer;
    display: inline-block;
    font-size: 15px;
    font-weight: normal;
    line-height: 30px;
    margin: 0;
    outline: none;
    padding: 0px 16px;
    position: relative;
    text-align: center;
    text-decoration: none;
    user-select: none;
    -webkit-user-select: none;
    touch-action: manipulation;
    vertical-align: baseline;
    white-space: nowrap;
    transition: color 200ms ease 0s, border-color 200ms ease 0s, background-color 200ms ease 0s;
}

#authorize-button:hover
#authorize-button:focus {
    background-color: #07c;
}

#authorize-button:focus {
    box-shadow: 0 0 0 4px rgba(0, 149, 255, .15);
}

#authorize-button:active {
    box-shadow: none;
}