CSS Effects Tools

box-shadow applies a shadow to the element's rectangular box (respecting border-radius). filter: drop-shadow() follows the actual rendered shape of the element, including transparent areas in PNG/SVG images. Use box-shadow for UI elements like cards and buttons. Use drop-shadow for images with transparency, icons, or irregularly shaped elements where you want the shadow to trace the content outline.

Neumorphism requires three things: a background color that matches the parent container, a light shadow offset toward the light source (typically top-left, using white or a lighter shade), and a dark shadow offset away from the light source (bottom-right, using a darker shade). The blur radius should be moderate. Example: `box-shadow: 8px 8px 16px #d1d1d1, -8px -8px 16px #ffffff` on a `#e8e8e8` background.

Box shadows are GPU-composited in modern browsers and perform well for typical usage. However, large blur radii (50px+), many shadow layers (5+), or shadows on hundreds of elements simultaneously can trigger expensive repaints. Avoid animating box-shadow directly — instead, animate `opacity` on a pseudo-element that already has the shadow applied, which allows the browser to composite rather than repaint.

Yes. Separate each shadow declaration with a comma in the box-shadow property. Shadows render in stack order — the first shadow is painted on top. This technique is essential for realistic depth: combine a small, sharp shadow (close definition) with a larger, blurred shadow (ambient light) and optionally an inset shadow for inner highlight.