blur background css with code examples

Blurring the background of an element in CSS can add a subtle effect that can help draw attention to the foreground content. There are several ways to achieve this effect, but one of the most popular is to use the ::before or ::after pseudo-elements to create a blurred copy of the background, and then use the opacity property to blend it with the original background.

Here's an example of how to create a blurred background for a div element:

<div class="blurred-bg">
  <p>Foreground content</p>
</div>

.blurred-bg {
  position: relative;
}

.blurred-bg::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: url(bg-image.jpg);
  filter: blur(5px);
  opacity: 0.5;
}

In this example, we're using the ::before pseudo-element to create a copy of the background image. We're positioning it absolutely so that it covers the entire div, and then using the filter property with the blur value of 5px to blur the image. Finally, we're using the opacity property to blend the blurred image with the original background image, making it appear more subtle.

You can also use the ::after pseudo-element instead of ::before.

Another way to achieve this effect is by using the backdrop-blur property. This property allows you to apply a blur effect to the background of an element without the need for a pseudo-element.

.blurred-bg {
  backdrop-blur: 10px;
}

This property is supported in most modern browsers, but not all.

You can also use JavaScript to blur the background.

var img = document.getElementById('bg-image');
img.style.filter = "blur(5px)";

In this example, we're using JavaScript to select the background image element by its ID and then applying the blur filter to it.

Overall, there are several ways to achieve a blurred background effect in CSS, each with its own advantages and disadvantages. Experiment with different methods and values to find the one that best fits your needs.

Another technique to create a blurred background is by using the box-shadow property. The box-shadow property allows you to apply a shadow effect to an element, and by using a large spread value and a transparent color, you can create a blurred background effect.

.blurred-bg {
  box-shadow: 0 0 40px 20px rgba(0, 0, 0, 0.5);
}

In this example, we're using the box-shadow property to apply a shadow with a horizontal offset of 0px, a vertical offset of 0px, a blur of 40px, a spread of 20px, and a color of rgba(0, 0, 0, 0.5). This creates a blurred background effect that blends the foreground content with the background.

Another way is by using the background-size and background-position properties to control the placement and size of the background image.

.blurred-bg {
  background: url(bg-image.jpg) no-repeat center center fixed;
  background-size: cover;
  filter: blur(5px);
}

In this example, we're using the background property to set the background image, with the no-repeat, center center and fixed values to control the placement of the image. Then we're using the background-size: cover to make sure that the image covers the entire element. Finally, we're using the filter property with the blur value of 5px to blur the image.

You can also use CSS Blend Modes to blend the background image with the foreground content.

.blurred-bg {
  background-image: url(bg-image.jpg);
  background-blend-mode: blur;
}

In this example, we're using the background-blend-mode property with the blur value to blend the background image with the foreground content. This can also be used with other blend modes like lighten, darken, overlay etc.

In addition, you can use CSS filter property brightness and contrast to change the brightness and contrast of the background image to make it more or less visible.

.blurred-bg {
  background-image: url(bg-image.jpg);
  filter: brightness(50%) contrast(200%);
}

In this example, we're using the filter property with the brightness value of 50% and contrast value of 200% to change the brightness and contrast of the background image.

Overall, there are many ways to achieve a blurred background effect in CSS, and each method has its own advantages and disadvantages. Experiment with different methods and values to find the one that best fits your needs. Keep in mind that some methods may not be supported by all browsers, so be sure to check browser compatibility before using them in production.

Popular questions

1. How can I create a blurred background using CSS?

• One way to create a blurred background using CSS is by using the ::before or ::after pseudo-elements to create a blurred copy of the background, and then using the opacity property to blend it with the original background. Another way is by using the box-shadow, background-size, background-position, background-blend-mode, or filter: blur() properties.

2. How do I use the ::before and ::after pseudo-elements to create a blurred background?

• To use the ::before and ::after pseudo-elements to create a blurred background, you can create a copy of the background image, position it absolutely to cover the entire element, apply a blur effect to the image using the filter property, and then use the opacity property to blend it with the original background.

3. Can I use JavaScript to create a blurred background?

• Yes, you can use JavaScript to create a blurred background by selecting the background image element using the DOM and applying a blur effect to it using the style.filter property.

4. How can I use the box-shadow property to create a blurred background?

• To use the box-shadow property to create a blurred background, you can apply a shadow with a large spread value and a transparent color to the element. This will create a blurred background effect that blends the foreground content with the background.

5. How can I use the background-blend-mode property to create a blurred background?

• To use the background-blend-mode property to create a blurred background, you can set the background image of the element and then use the background-blend-mode property with the blur value to blend the background image with the foreground content. This can also be used with other blend modes like lighten, darken, overlay etc.

Tag

Blur