Usando gradientes con CSS

CSS3 posee soporte para nuevos tipos de gradientes  en las propiedades CSS. Usarlos en un segundo plano, permite mostrar transiciones suaves entre dos o más colores especificados, evitando así el uso de imágenes para estos efectos, lo que reduce el tiempo de descarga y el uso de ancho de banda. Además, debido a que el gradiente es generado por el navegador, los objetos degradados se ven mejor cuando se hace un acercamiento, y el ajuste de diseño es mucho más flexible.

Los navegadores soportan dos tipos de gradientes: lineal, definido con la función linear-gradient, y radial, definido con radial-gradient.

Gradiente lineal

Para crear un gradiente lineal, se establece un punto de partida y una dirección (indicada por un ángulo) a lo largo de la cual se aplica el efecto. You also define color stops. Color stops are the colors you want Gecko to render smooth transitions among, and you must specify at least two of them, but can specify more to create more complex gradient effects.

Simple linear gradients

Here's a linear gradient that starts at the center (horizontally) and top (vertically), and starts blue, transitioning to white.

Screen Shot	Live Demo

/* The old syntax, deprecated, but still needed, prefixed, for Opera and WebKit-based browsers */
background: -prefix-linear-gradient(top, blue, white); 

/* The new syntax needed by standard-compliant browsers (IE 10 and Firefox 10 onwards), without prefix */
background: linear-gradient(to bottom, blue, white);

Changing the same gradient to run from left to right:

Screen Shot	Live Demo

/* The old syntax, deprecated, but still needed, prefixed, for Opera and WebKit-based browsers */
background: -prefix-linear-gradient(left, blue, white); 

/* The new syntax needed by standard-compliant browsers (IE 10 and Firefox 10 onwards), without prefix */
background: linear-gradient(to right, blue, white);

You can make the gradient run diagonally by specifying both the horizontal and vertical starting positions. For example:

Screen Shot	Live Demo

/* The old syntax, deprecated, but still needed, prefixed, for Opera and WebKit-based browsers */
background: -prefix-linear-gradient(left top, blue, white); 

/* The new syntax needed by standard-compliant browsers (IE 10 and Firefox 10 onwards), without prefix */
background: linear-gradient(to bottom right, blue, white);

Using angles

If you don't specify an angle, one is determined automatically based on the given direction. If you'd like more control over the direction of the gradient, you can set the angle specifically.

For example, here are two gradients, the first one with a direction of towards the right, and the second one has an angle of 70 degrees.

The one on the right uses CSS like this:

background: linear-gradient(70deg, black, white);

The angle is specified as an angle between a horizontal line and the gradient line, going counter-clockwise. In other words, 0deg creates a vertical gradient from the bottom to the top, while 90deg generates a left to right horizontal gradient :

background: linear-gradient(<angle>, red, white);

Color stops

Color stops are points along the gradient line that will have a specific color at that location. The location can be specified as either a percentage of the length of the line, or as an absolute length. You may specify as many color stops as you like in order to achieve the desired effect.

If you specify the location as a percentage, 0% represents the starting point, while 100% represents the ending point; however, you can use values outside that range if necessary to get the effect you want.

Example: Three color stops

This example specifies three color stops:

Screen Shot	Live Demo

/* The old syntax, deprecated, but still needed, prefixed, for Opera and WebKit-based browsers */
background: -prefix-linear-gradient(top, blue, white 80%, orange);

/* The new syntax needed by standard-compliant browsers (IE 10 and Firefox 10 onwards), without prefix */
background: linear-gradient(to bottom, blue, white 80%, orange);

Note that the first and last color stops don't specify a location; because of that, values of 0% and 100% are assigned automatically. The middle color stop specifies a location of 80%, putting it most of the way toward the bottom.

Example: Evenly spaced color stops

Here's an example using a wide variety of colors, all evenly spaced:

Screen Shot	Live Demo

/* The old syntax, deprecated, but still needed, prefixed, for Opera and WebKit-based browsers */
background: -prefix-linear-gradient(left, red, orange, yellow, green, blue);

/* The new syntax needed by standard-compliant browsers (IE 10 and Firefox 10 onwards), without prefix */
background: linear-gradient(to right, red, orange, yellow, green, blue);

Notice that the color stops are automatically spaced evenly when no locations are specified.

Transparency and gradients

Gradients support transparency. You can use this, for example, when stacking multiple backgrounds, to create fading effects on background images. For example:

/* The old syntax, deprecated, but still needed, prefixed, for Opera and WebKit-based browsers */ 
background: linear-gradient(left, rgba(255,255,255,0), rgba(255,255,255,1)), url(https://foo.com/image.jpg);

/* The new syntax needed by standard-compliant browsers (IE 10 and Firefox 10 onwards), without prefix */  
background: linear-gradient(to right, rgba(255,255,255,0), rgba(255,255,255,1)), url(https://foo.com/image.jpg);

The backgrounds are stacked with the first specified background on top, and each successive background farther away. By stacking backgrounds this way, you can create very creative effects as seen above.

Radial gradients

Radial gradients are specified using the radial-gradient functional notation. The syntax is similar to that for linear gradients, except you can specify the gradient's ending shape (whether it should be a circle or ellipse) as well as its size. By default, the ending shape is an ellipse with the same proportions than the container's box.

Color stops

You specify color stops the same way as for linear gradients. The gradient line extends out from the starting position in all directions.

Example: Evenly spaced color stops

By default, as with linear gradients, the color stops are evenly spaced:

Screen Shot	Live Demo

background: radial-gradient(red, yellow, rgb(30, 144, 255));

Example: Explicitly spaced color stops

Here we specify specific locations for the color stops:

Screen Shot	Live Demo

background: radial-gradient(red 5%, yellow 25%, #1E90FF 50%);

Size

This is one of the areas in which radial gradients differ from linear gradients. You can provide a size value that specifies the point that defines the size of the circle or ellipse. See this description of the size constants for specifics.

Example: closest-side for ellipses

This ellipse uses the closest-side size value, which means the size is set by the distance from the starting point (the center) to the closest side of the enclosing box.

Screen Shot	Live Demo

background: radial-gradient(ellipse closest-side, red, yellow 10%, #1E90FF 50%, white);

Example: farthest-corner for ellipses

This example is similar to the previous one, except that its size is specified as farthest-corner, which sets the size of the gradient by the distance from the starting point to the farthest corner of the enclosing box from the starting point.

Screen Shot	Live Demo

background: radial-gradient(ellipse farthest-corner, red, yellow 10%, #1E90FF 50%, white);

Example: closest-side for circles

This example uses closest-side, which determines the circle's size as the distance between the start point (the center) and the closest side.

Screen Shot	Live Demo

background: radial-gradient(circle closest-side, red, yellow 10%, #1E90FF 50%, white);

Here, the circle's radius is half the height of the box, since the top and bottom edges are equidistant from the start point and are closer than the left and right edges.

Repeating gradients

The linear-gradient and radial-gradient properties don't support automatically repeating the color stops. However, the repeating-linear-gradient and repeating-radial-gradient properties are available to offer this functionality.

Examples: Repeating linear gradient

This example uses repeating-linear-gradient to create a gradient:

Screen Shot	Live Demo

background: repeating-linear-gradient(-45deg, red, red 5px, white 5px, white 10px);

Another example using the repeating-linear-gradient property.

background-color: #000;
background-image: repeating-linear-gradient(90deg, transparent, transparent 50px,
      rgba(255, 127, 0, 0.25) 50px, rgba(255, 127, 0, 0.25) 56px, transparent 56px, transparent 63px,
      rgba(255, 127, 0, 0.25) 63px, rgba(255, 127, 0, 0.25) 69px, transparent 69px, transparent 116px,
      rgba(255, 206, 0, 0.25) 116px, rgba(255, 206, 0, 0.25) 166px),
repeating-linear-gradient(0deg, transparent, transparent 50px, rgba(255, 127, 0, 0.25) 50px,
      rgba(255, 127, 0, 0.25) 56px, transparent 56px, transparent 63px, rgba(255, 127, 0, 0.25) 63px,
      rgba(255, 127, 0, 0.25) 69px, transparent 69px, transparent 116px, rgba(255, 206, 0, 0.25) 116px,
      rgba(255, 206, 0, 0.25) 166px),
repeating-linear-gradient(-45deg, transparent, transparent 5px, rgba(143, 77, 63, 0.25) 5px,
      rgba(143, 77, 63, 0.25) 10px),
repeating-linear-gradient(45deg, transparent, transparent 5px, rgba(143, 77, 63, 0.25) 5px,
      rgba(143, 77, 63, 0.25) 10px);

Example: Repeating radial gradient

This example uses repeating-radial-gradient to create a gradient:

Screen Shot	Live Demo

background: repeating-radial-gradient(black, black 5px, white 5px, white 10px);

See also

• Gradient-related reference articles: <image>, <gradient>, linear-gradient, radial-gradient, repeating-linear-gradient, repeating-radial-gradient.