css to achieve animation effects

CSS is a language used to design web page styles. It can not only make web pages more beautiful, but also achieve various animation effects. In this article, I will explain in detail how to use CSS to achieve animation effects.

Basic concepts

Before we start learning CSS animation effects, we must first understand some basic concepts. The more important ones are: animation keyframes, animation duration, animation speed, animation direction and animation fill mode.

Animation key frames

Animation key frames refer to specific key points in the animation. In CSS animation, we can define multiple keyframes, each keyframe defines a state in the animation. By transitioning between these keyframes, a complete animation effect can be formed.

Animation duration

Animation duration refers to the total time from the beginning to the end of the animation. We can use the animation-duration property of CSS to specify the duration of the animation in seconds or milliseconds.

Animation speed

Animation speed refers to the playback speed of animation. In CSS, we can use the animation-timing-function attribute to specify the speed of the animation. Its value can be linear (linear), ease (ease in and ease out), ease-in (ease in), ease-out (exit) Ease) and ease-in-out (enter and exit ease), etc.

Animation direction

The animation direction refers to the playback direction of the animation. In CSS, we can use the animation-direction attribute to specify the direction of the animation. Its value can be normal (forward playback), reverse (reverse playback), alternate (alternative playback) and alternate-reverse (reverse alternate playback). )wait.

Animation fill mode

Animation fill mode refers to the state of the element before the animation starts and after it ends. In CSS, we can use the animation-fill-mode attribute to specify the state before and after the animation starts. Its value can be none (default value, no processing is done), forwards (the final state is the state when the animation ends), backwards (the initial state is the state when the animation starts), and both (both forwards and backwards are applied), etc. .

Implementation method

After understanding the basic concepts of CSS animation, we begin to introduce how to achieve animation effects.

Step 1: Define key frames

First, we need to use the @keyframes keyword to define key frames. For example, the following code defines a keyframe named "slidein" that moves elements from left to right:

@keyframes slidein{

from{ left:-100%; } to{ left:0; }

}

The above code , the name of the keyframe is slidein, which defines two states: from (starting state, the left border of the element is located at the far left side of the browser) and to (end state, the left border of the element is located at the far right side of the browser) ).

We can also use percentages to define the state of keyframes. For example, the following code defines an animation that moves an element from left to right, pauses at 30%, and then continues moving to the right:

@keyframes slidein{

0%{ left:-100%; } 30%{ left:50%; } 100%{ left:0; }

}

Step 2: Apply animation

After defining the keyframes, we need to apply animation to the elements that require animation effects. This function can be achieved using the animation property of CSS. For example, the following code applies an animation named "slidein" to an element and specifies the animation's duration, speed, direction, and fill mode:

.element{

animation-name:slidein; animation-duration:2s; animation-timing-function:ease-in-out; animation-directioin:normal; animation-fill-mode:forwards;

}

In the above code, the name of the animation is "slidein", its duration is 2 seconds, the speed is ease-in and ease-out, the direction is forward playback, and the fill mode is the final state, which is the same as the state at the end of the animation. .

It should be noted that the animation attribute can be abbreviated as animation: animation name or animation: animation name duration speed direction fill mode.

Step 3: Set other animation properties

After applying the animation to the element, we can also set other animation properties, such as animation delay time, etc. We can use the animation-delay property to set the animation delay time in seconds or milliseconds. For example, the following code starts playing the animation after 2 seconds:

.element{

animation-name:slidein; animation-duration:2s; animation-timing-function:ease-in-out; animation-directioin:normal; animation-fill-mode:forwards; animation-delay:2s;

}

Summary

Through the above steps, we can Use CSS to easily achieve various animation effects. It should be noted that different browsers may have slightly different levels of CSS support, so pay attention to testing and adaptation when writing code.

CSS animation can make web pages more vivid and interesting, attract users' attention, and improve user experience. I hope the introduction in this article can help readers better understand CSS animation and make web design more outstanding.

The above is the detailed content of css to achieve animation effects. For more information, please follow other related articles on the PHP Chinese website!