Applying Drop Shadow to Irregularly Shaped PNG Images Using CSS

The standard approach to applying a drop shadow to a PNG image using -o-box-shadow, -icab-box-shadow, -khtml-box-shadow, -moz-box-shadow, -webkit-box-shadow, or box-shadow properties treats the image as a square. This can result in the shadow not conforming to the actual shape of the image.

To apply a drop shadow that accurately follows the contours of a non-square PNG image, you can use the CSS filter: dropShadow() property. This property syntax is as follows:

filter: drop-shadow(x y blur? color?);

Here, x and y represent the horizontal and vertical offsets of the shadow, respectively, while blur defines the fuzziness of the shadow edges. The optional color parameter sets the shadow color.

This technique can be applied using regular CSS rules:

img {
  -webkit-filter: drop-shadow(5px 5px 5px #222);
  filter: drop-shadow(5px 5px 5px #222);
}

Alternatively, you can specify the filter inline for individual images:

By using the filter: dropShadow() property, you can achieve accurate drop shadows on irregularly shaped PNG images, enhancing their visual appeal and adding depth to your designs.