.flappy-game {
    overflow: hidden;
    background: #000;
    touch-action: none;
    user-select: none;
    cursor: pointer;
}

/* Stage is 1920×1080 or larger to match the window's shape (sized in flappy.js), then scaled to fill it. */
.tb-stage {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 1920px;
    height: 1080px;
    overflow: hidden;
    background: #12123a;
    transform-origin: center;
}

.tb-background,
.tb-dim,
.tb-canvas {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
}

.tb-background {
    object-fit: cover;
    filter: saturate(0.6) blur(1.5px);
}

.tb-canvas {
    image-rendering: pixelated;
}

/* NIGHT / DAY switch under the splash-screen keys (stage px; the stage is scaled as a whole). */
.tb-theme-toggle {
    position: absolute;
    top: calc(50% + 236px);
    left: 50%;
    display: flex;
    border: 4px solid #eaf3ff;
    transform: translateX(-50%);
}

.tb-theme-toggle[hidden] {
    display: none;
}

.tb-theme-toggle button {
    padding: 0 24px;
    border: 0;
    background: #0b0a1a;
    color: #eaf3ff;
    font: 40px/1.2 "Jersey 10", monospace;
    letter-spacing: 3px;
    cursor: pointer;
}

.tb-theme-toggle button[aria-pressed="true"] {
    background: #eaf3ff;
    color: #0b0a1a;
}

.tb-theme-toggle button:focus-visible {
    outline: 4px solid #e0262f;
    outline-offset: 4px;
}

/* GitHub / X links, top-right corner of the splash screen. Icons are on a 12 px grid, drawn at 4×. */
.tb-social {
    position: absolute;
    top: 48px;
    right: 48px;
    display: flex;
    gap: 16px;
}

.tb-social[hidden] {
    display: none;
}

.tb-social a {
    display: grid;
    place-items: center;
    width: 80px;
    height: 80px;
    border: 4px solid #eaf3ff;
    background: #0b0a1a;
    color: #eaf3ff;
}

.tb-social a:hover {
    background: #eaf3ff;
    color: #0b0a1a;
}

.tb-social a:focus-visible {
    outline: 4px solid #e0262f;
    outline-offset: 4px;
}

.tb-social svg {
    width: 48px;
    height: 48px;
    shape-rendering: crispEdges;
}

.tb-visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip-path: inset(50%);
    white-space: nowrap;
}