How to 'Resize' Images with CSS

While CSS3 can't "resize" images directly, you can use media query and responsive design principles to make images look resized in the browser.

The concept is to make the image responsive to the viewport size, ensuring that the image does not exceed the edge. If the viewport height is greater than the width, the maximum width must be defined; if the viewport width is greater than the height, the maximum height must be defined.

The following are some sample code and links to more related articles. Please note that the use of img.ri:empty is a structural pseudo-class that only matches elements without child elements (the image should not have any child elements). This is a CSS3 selector, so IE8 and below will not be able to resolve the declaration. empty

@media screen and (orientation: portrait) {
  img.ri { max-width: 90%; }
}

@media screen and (orientation: landscape) {
  img.ri { max-height: 90%; }
}

More information about responsive images, here are some articles with more information on creating responsive centered images, guides on maintaining image aspect ratios using CSS3, and a complete guide on the

properties. background-size

FAQ on CSS Image Size Resolution

How to resize the image in CSS without losing quality?

Resizing the image size in CSS without losing quality requires the correct CSS properties. The image size can be resized using the

and width properties. However, to maintain aspect ratio and prevent deformation, only one of the properties should be specified and the other should be set to height. For example: auto

img {
  width: 100%;
  height: auto;
}

This code will resize the image to fit the width of its container while maintaining its aspect ratio, thus maintaining its mass.

What is the role of the

attribute in CSS image resizing?

The object-fit attribute in the

CSS is used to specify how to resize an image or video to fit its container. It has five possible values:

, object-fit, fill, contain, cover, and none. The scale-down value stretches the image to fit the container, which may deform the image if the aspect ratio of the image is different from that of the container. The fill value resizes the image to fit the container while maintaining its aspect ratio, which may leave some uncovered space in the container. The contain value resizes the image to cover the entire container while maintaining its aspect ratio, which may crop certain parts of the image. The cover value does not resize the image at all. The value of none behaves like scale-down or contain, taking the smaller one. none

How to make images responsive using CSS?

Making the image responsive in CSS requires the use of the

attribute, whose value is max-width. This allows the image to shrink when needed, but never to be enlarged beyond its original size. For example: 100%

img {
  max-width: 100%;
  height: auto;
}

This code will make the image responsive, meaning it will resize itself according to the size of its container, and it will maintain its aspect ratio, thus preventing deformation.

How to resize background image using CSS?

Resize the background image in CSS and use the background-size attribute. It has several possible values, including auto, cover, contain and specific sizes. The auto value resizes the background image to its actual size. The cover value resizes the background image to cover the entire container, even if it has to stretch the image or crop a little from its edge. The contain value resizes the background image to ensure that the image is fully visible. A specific size can be given to adjust the background image to a certain width and height. For example:

@media screen and (orientation: portrait) {
  img.ri { max-width: 90%; }
}

@media screen and (orientation: landscape) {
  img.ri { max-height: 90%; }
}

This code will resize the background image to cover the entire body of the web page.

How to adjust an image to a specific width and height in CSS?

Adjusting the image to a specific width and height in CSS requires the use of width and height properties as well as specific values. However, this may deform the image if the aspect ratio of the image is different from the specified width and height ratio. To prevent deformation, only one of the properties should be specified and the other should be set to auto. For example:

img {
  width: 100%;
  height: auto;
}

This code adjusts the image to 500 pixels wide while maintaining its aspect ratio.

How to center the image after resizing it in CSS?

Center the image after resizing it in CSS. You can use the margin attribute, whose value is auto. This works when the image is displayed as a block-level element and can be specified using the display attribute and block value. For example:

img {
  max-width: 100%;
  height: auto;
}

This code centers the image horizontally within its container.

How to resize the image in CSS without stretching it?

Resize the image in CSS without stretching it, and its aspect ratio needs to be maintained. This can be done by specifying only one of the width and height properties and setting the other property to auto. For example:

body {
  background-image: url("image.jpg");
  background-size: cover;
}

This code resizes the image to fit the width of its container while maintaining its aspect ratio, thus preventing stretching.

How to resize an image in CSS and maintain its aspect ratio?

Resize the image in CSS and maintain its aspect ratio, you need to specify only one of the width and height properties and set the other property to auto. For example:

img {
  width: 500px;
  height: auto;
}

This code resizes the image to fit the width of its container while maintaining its aspect ratio.

How to resize the image in CSS to fit the screen?

Resize the image in CSS to fit the screen, use vw (viewport width) units as the value of the width attribute, and vh (viewport height) units as the value of the height attribute. For example:

img {
  display: block;
  margin: auto;
}

This code will resize the image to fit the entire screen regardless of the screen size.

How to resize the image in CSS to fill its container?

Resize the image in CSS to fill its container, you need to use the object-fit attribute, whose value is fill. For example:

@media screen and (orientation: portrait) {
  img.ri { max-width: 90%; }
}

@media screen and (orientation: landscape) {
  img.ri { max-height: 90%; }
}

This code will stretch the image to fit its container, which may deform the image if the aspect ratio of the image is different from that of the container. To prevent deformation, you can use the object-fit attribute, whose value is cover, which will resize the image to cover the entire container while maintaining its aspect ratio, even if it has to crop certain parts of the image.

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