CSS (Cascading Style Sheets) is a language used for web design that can control the style and layout in HTML documents. In web development, various visual effects can be achieved using CSS, including circular effects.
There are many ways to achieve a circle, including using the border-radius attribute, using pseudo-elements, and using SVG. Below we will introduce some basic methods to achieve CSS circles.
The border-radius property of CSS can turn a square element into a circle by setting the corner radius of the element to 50%. This will turn the element into a circle. For example, the following code turns a div element into a circle:
.circle { width: 100px; height: 100px; border-radius: 50%; }
This code turns a div element with a width and height of 100 pixels into a circle.
border-radius can also be used to create ellipses by setting the two radius properties to the horizontal and vertical radii respectively.
.ellipse { width: 150px; height: 100px; border-radius: 50% 25% / 50% 25%; }
This code turns a div element with a width of 150 pixels and a height of 100 pixels into an oval. The horizontal radius is 50% and the vertical radius is 25%.
CSS pseudo-elements (::before and ::after) can be used to create a circle and place it somewhere on the element. location. For example, the following code can set a pseudo element to a circle with a radius of 50%:
.circle { position: relative; width: 100px; height: 100px; } .circle::before { content: ""; position: absolute; top: 0; left: 0; width: 100%; height: 100%; border-radius: 50%; }
This code turns a div element with a width and height of 100 pixels into a pseudo element with a circle Element's round shape.
SVG (Scalable Vector Graphics) is a vector graphics format that can be used for web development. Circles can be easily created using SVG while controlling the size and color of the graphic.
The code below shows how to create a circle with a 50 pixel radius using SVG:
<svg viewBox="0 0 100 100"> <circle cx="50" cy="50" r="50"/> </svg>
This code will create an SVG element with a viewbox size of 100×100 that contains a radius A circle of 50 degrees. The cx and cy attributes define the location of the center of the circle.
Unlike CSS, SVG is a vector graphics format and therefore can be scaled without distortion. SVG can also be styled using CSS styles, such as setting the color and shadow of a circle, etc.
Summary:
The above are several ways to use CSS to achieve a circle. In web development, visual effects can be easily created using these methods and can be styled as desired. Different methods are suitable for different scenarios, and developers should choose the method that suits them best.
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