SVG Properties and CSS

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Katherine Kato on (Updated on )

SVG has its own set of elements, attributes and properties to the extent that inline SVG code can get long and complex. By leveraging CSS and some of the forthcoming features of the SVG 2 specification, we can reduce that code for cleaner markup.

There are many Scalable Vector Graphics (SVG), but only certain attributes can be applied as CSS to SVG. Presentation attributes are used to style SVG elements and can be used as CSS properties. Some of these attributes are SVG-only while others are already shared in CSS, such as font-size or opacity.

For example, to change the color of a element to red, use the fill property in CSS. The fill attribute is a presentation attribute, therefore it can be used as a CSS property:

circle {
  fill: red;
}

So, with that, let’s take a deep and thorough dive into all of the SVG elements that are available to us as well as the CSS properties for them. We’ll also look at various styling approaches, including general presentational styles and animations.

SVG Elements by Category

The presentation attributes that can be used as CSS properties can be found below. For reference, supported elements will be classified by category. This does not include deprecated elements.

Element TypeElements
Container elements<a>
<defs>
<g>
<marker>
<mask>
<pattern>
<svg>
<switch>
<symbol>
Filter primitive elements<feBlend>
<feColorMatrix>
<feComponentTransfer>
<feComposite>
<feConvolveMatrix>
<feDiffuseLighting>
<feDisplacementMap>
<feFlood>
<feGaussianBlur>
<feImage>
<feMerge>
<feMorphology>
<feOffset>
<feSpecularLighting>
<feTile>
<feTurbulence>
Gradient elements<linearGradient>
<radialGradient>
<stop>
Graphics elements<circle>
<ellipse>
<image>
<line>
<path>
<polygon>
<polyline>
<rect>
<text>
<use>
Shape elements<circle>
<ellipse>
<line>
<path>
<polygon>
<polyline>
<rect>
Text content elements<text>
<textPath>
<tspan>

Properties shared between CSS and SVG

Font properties

Presentation attributeSupported elements
fontText content elements
font-familyText content elements
font-sizeText content elements
font-size-adjustText content elements
font-stretchText content elements
font-styleText content elements
font-variantText content elements
font-weightText content elements

Text properties

Presentation attributeSupported elements
direction<text>
<tspan>
letter-spacingText content elements
text-decorationText content elements
unicode-bidiText content elements
word-spacingText content elements
writing-mode<text>

Masking properties

Presentation attributeSupported elements
overflow<foreignObject>
<image>
<marker>
<pattern>
<svg>
<symbol>

Interactivity properties

Presentation attributeSupported elements
cursorContainer elements
Graphics elements

Color properties

Presentation attributeSupported elements
colorApplies to elements using:
fill
stroke
stop-color
flood-color
lighting-color

Visibility properties

Presentation attributeSupported elements
displayGraphics elements
Text content elements
<a>
<foreignObject>
<g>
<svg>
<switch>
visibilityGraphics elements
Text content elements

SVG CSS Properties

Text properties

Presentation attributeSupported elements
alignment-baseline<textPath>
<tspan>
baseline-shift<textPath>
<tspan>
dominant-baselineText content elements
glyph-orientation-horizontalText content elements
glyph-orientation-verticalText content elements
kerningText content elements
text-anchorText content elements

Clip properties

Presentation attributeSupported elements
clip<foreignObject>
<image>
<marker>
<pattern>
<svg>
<symbol>
clip-pathContainer elements
Graphics elements
clip-rule<clipPath>

Masking properties

Presentation attributeSupported elements
maskContainer elements
Graphics elements
opacityGraphics elements
<a>
<defs>
<g>
<marker>
<pattern>
<svg>
<switch>
<symbol>

Filter effects

Presentation attributeSupported elements
enable-backgroundContainer elements
filterContainer elements
Graphics elements
flood-color<feFlood>
flood-opacity<feFlood>
lighting-color<feDiffuseLighting>
<feSpecularLighting>

Gradient properties

Presentation attributeSupported elements
stop-color<stop>
stop-opacity<stop>

Interactivity properties

Presentation attributeSupported elements
pointer-eventsGraphics elements

Color properties

Presentation attributeSupported elements
color-profile<image> referring to raster image

Painting properties

Presentation attributeSupported elements
color-interpolationContainer elements
Graphics elements
color-interpolation-filtersFilter primitive elements
color-renderingContainer elements
Graphics elements
fillShape elements
Text content elements
fill-ruleShape elements
Text content elements
fill-opacityShape elements
Text content elements
image-rendering<image>
marker<line>
<path>
<polygon>
<polyline>
marker-start<line>
<path>
<polygon>
<polyline>
marker-mid<line>
<path>
<polygon>
<polyline>
marker-end<line>
<path>
<polygon>
<polyline>
shape-renderingShape elements
strokeShape elements
Text content elements
stroke-dasharrayShape elements
Text content elements
stroke-dashoffsetShape elements
Text content elements
stroke-linecapShape elements
Text content elements
stroke-linejoinShape elements
Text content elements
stroke-miterlimitShape elements
Text content elements
stroke-opacityShape elements
Text content elements
stroke-widthShape elements
Text content elements
text-rendering<text>

SVG 2

While presentation attributes can be used as CSS properties to style SVG, what about controlling the coordinates and dimensions of SVG elements using CSS? SVG 2, which is in Candidate Recommendation at the time of this writing, makes it is possible to style and animate these properties.

The SVG 2 specification states:

Some styling properties can be specified not only in style sheets and ‘style‘ attributes, but also in presentation attributes. These are attributes whose name matches (or is similar to) a given CSS property and whose value is parsed as a value of that property.”

Not only does it mean that SVG properties can be styled using CSS as presentation attributes or in style sheets, but this also can be applied to CSS pseudo-classes such as :hover or :active.

SVG 2 also introduces more presentation attributes that can be used as styling properties. These attributes can be found in SVG 2 specification.

Element-specific properties

It is important to note that not every SVG element will support the same CSS properties. Much like how there are CSS properties that can be applied to certain SVG elements, there are specific properties that are supported by certain SVG elements.

For example, the <circle> or <ellipse> elements support the cxand cyproperties as coordinates of the center of the shape. The element also supports the rx and ry properties as the radius, but the element cannot use these properties.

Geometry properties

In SVG 2, properties such as rx and ry are defined as geometry properties. Geometry properties can be used as CSS properties, just like presentation attributes such as fill or stroke properties. These CSS properties and the corresponding SVG elements include:

SVG ElementGeometry Property
<circle>cx
cy
r
<ellipse>cx
cy
rx
ry
<rect>rx
ry
height
width
x
y
<path>path
<image>height
width
x
y
<foreignObject>height
width
x
y
<svg>height
width
x
y

Positioning SVG elements

SVG 2 also makes it is possible to position SVG elements using CSS. Let’s begin with drawing a rectangle shape having the following SVG:

<svg width="170" height="170">
  <rect x="10" y="10" width="150" height="150" />
</svg>

And the following CSS:

rect {
  fill: #6e40aa;
}

This will produce a rectangle shape with its coordinates set to 10, 10. With SVG 2, x and y can be applied as CSS properties:

/* This will work with SVG 2 */
rect {
  x: 10;
  y: 10;
  ...
}

The SVG code would be reduced to this:

<svg width="170" height="170">
  <rect width="150" height="150" />
</svg>

You can even set the width and height for the <rect> element using CSS like so:

rect {
  ...
  width: 150px;
  height: 150px;
  ...
}

That leaves us with just the following for SVG markup:

<svg width="170" height="170">
  <rect />
</svg>

At the time of writing, the following demos will work in Blink (e.g. Chrome and Opera) and WebKit (e.g. Safari) browsers as these browsers support SVG 2 features. Until then, let’s dive into how to override SVG properties using CSS.

SVG shape morphing

The element can be overridden with CSS to create shape morphing.

The SVG paths that morph one into the other must have the same commands and same number of points or else the morphing will not work.

Let’s start with drawing a element in the shape of a triangle. Using the d property will specify the shape of the element:

<svg height="220" width="300">
  <path d="M150 10 L40 200 L260 200Z" />
</svg>

To get the triangle to morph into a different shape, let’s override the SVG element with the d property with CSS:

path {
  d: path("M150, 10 L40, 200 L260, 200Z");
  fill: #4c6edb;
}

Let’s also add a :active pseudo-class to the property so when the element is clicked, the shape will morph into a square and change its fill color. Let’s also add a transition property to make the shape morphing action appear smooth. Here is the CSS:

path:active {
  d: path("M150, 10 L40, 200 L260, 200 L260, 200Z");
  fill: #4c6edb;
  transition: all 0.35s ease;
}

And the SVG would be:

<svg height="220" width="300">
  <path />
</svg>

Want another demo? Here is a cool demo from Chris Coyier demonstrating SVG shape morphing on hover!

Animating SVG properties

SVG properties can be animated using CSS through CSS animations and transitions.

In this demo, we will draw various SVG elements and create a wave animation. Start by drawing five elements:

<svg width="350" height="250">
  <circle class="shape" />
  <circle class="shape" />
  <circle class="shape" />
  <circle class="shape" />
  <circle class="shape" />
</svg>

We’ll be using CSS variables and :nth-child() CSS pseudo-class to define each .shape class. The .shape class will have a cy of 50 and a r of 20. Each of the .shape classes will have their own cx and fill CSS properties set:

:root {
  --color-1: #6e40aa;
  --color-2: #4c6edb;
  --color-3: #24aad8;
  --color-4: #1ac7c2;
  --color-5: #1ddea3;
}

.shape {
  cy: 50;
  r: 20;
}

.shape:nth-child(1) {
  cx: 60;
  fill: var(--color-1);
}

.shape:nth-child(2) {
  cx: 120;
  fill: var(--color-2);
}

.shape:nth-child(3) {
  cx: 180;
  fill: var(--color-3);
}

.shape:nth-child(4) {
  cx: 240;
  fill: var(--color-4);
}

.shape:nth-child(5) {
  cx: 300;
  fill: var(--color-5);
}

Here is how it should look so far.

Now it’s time to animate! Start by using @keyframes rule to define the moveCircle animation:

@keyframes moveCircle {
  50% {
    cy: 150;
    r: 13;
  }
}

This will get each element to change their cy coordinates from 50 to 150 and r from 20 to 13. Add the following to the CSS to the .shape class get the animation running infinitely:

.shape {
  ...
  animation: moveCircle 1250ms ease-in-out both infinite;
}

Finally, add an animation-delay to each of the .shape classes to the CSS with the exception of .shape:nth-child(1) like this:

.shape:nth-child(2) {
  ...
  animation-delay: 100ms;
}

.shape:nth-child(3) {
  ...
  animation-delay: 200ms;
}

.shape:nth-child(4) {
  ...
  animation-delay: 300ms;
}

.shape:nth-child(5) {
  ...
  animation-delay: 400ms;
}

Shapes in SVG <pattern> elements can also be animated using CSS. Here is a cool demo by Dudley Storey showcasing that!

Wrapping up

As SVG 1.1 is the current standard, few browsers currently support SVG 2 features. It is not recommended to put these techniques into production yet. SVG 2 implementation is currently at Candidate Recommendation stage, thus support for styling SVG geometry properties with CSS should improve in the future.