Backgrounds¶

Slide backgrounds map to reveal.js data-background-* attributes. You do not need background classes for typical use; pass plain values to bg().

Plain values (preferred)¶

from pyreveal import BackgroundSize, BackgroundType, Presentation, Slide

# Color string
slide = Slide()
slide.title = "Colored"
slide.bg("#2d3436")

# Image path
slide.bg("photos/bg.jpg")

# Image with options
slide.bg(image="bg.jpg", size=BackgroundSize.COVER, opacity=0.6)

# Explicit type via enum
slide.bg(type=BackgroundType.GRADIENT, gradient="linear-gradient(to bottom, #283b95, #17b2c3)")

# Video
slide.bg(type=BackgroundType.VIDEO, video="assets/loop.mp4")

# Iframe
slide.bg(
    type=BackgroundType.IFRAME,
    iframe="https://example.com",
    interactive=True,
)

Deck default background¶

Apply a background to every slide that does not set its own:

deck = Presentation("Talk")
deck.bg("#1a1a2e", opacity=0.9)
# or
deck.bg("default-bg.jpg")

Shared options¶

All background types accept optional opacity, position, repeat, transition, and parallax.

slide.bg(image="bg.jpg", size=BackgroundSize.COVER, opacity=0.6, position="center")
slide.bg(image="bg.jpg", parallax="2")  # per-slide parallax multiplier

Deck-wide parallax background¶

For a single large background that scrolls as you move through the deck, use Presentation.parallax_background():

deck = Presentation("Talk")
deck.parallax_background(
    "assets/parallax.jpg",
    size="2100px 900px",
    horizontal=200,
    vertical=50,
)

This maps to reveal.js parallaxBackground* config options. See reveal.js parallax backgrounds.

Video with multiple formats¶

slide.bg(
    type=BackgroundType.VIDEO,
    sources=["clip.mp4", "clip.webm"],
    preload=True,
)

Advanced: background classes¶

For fine-grained control, background classes remain available:

from pyreveal import ColorBackground, GradientBackground, ImageBackground

slide.bg(ColorBackground("#2d3436"))
slide.bg(ImageBackground("bg.jpg", size="cover"))

Factory helper¶

from pyreveal import BackgroundFactory, BackgroundType

bg = BackgroundFactory.create_background(BackgroundType.COLOR, "#1a1a2e")
bg = BackgroundFactory.create_background(BackgroundType.IMAGE, "bg.jpg", size="cover")