:root {
    /* App canvas background. Defaults to the dark theme base (TetPalette.Ink900,
       --bg-base) — the app's default theme. The inline head script in index.html
       flips it to the light base when the user has saved the light theme, so
       collapsing the mobile keyboard never flashes white behind the Compose canvas. */
    --app-bg: #110D20;
}

html, body {
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
    overflow: hidden;
    background-color: var(--app-bg);
}

body {
    position: fixed;
    top: 0;
    left: 0;
}