Click or tap anywhere on the screen and a firework rises from that spot. The more you keep pressing, the more bloom at once. Use the Color, Motion, Shape, and Environment panels to fine-tune how your fireworks look.
Drag the heading at the top of a panel to move it wherever you like. In the Environment panel you can toggle auto-launch and the starry sky. From the Output panel, you can save your finished fireworks as PNG or SVG images or a WebM video.
Double-click a panel title to switch how the panels are laid out. In the movable layout you drag panels wherever you like and keep several open at once; in the fixed layout a single panel sits in the top right.