web前端入门到实战：超酷的 CSS3 loading 预加载动画特效

给大家介绍一款超酷CSS3 loading预加载动画特效。

该loading特效共有4种不同的效果，分别通过不同的CSS3 keyframes帧动画来完成。

HTML结构

4种loading预加载动画的HTML结构分别如下：

对web前端这门技术感兴趣的小伙伴可以加入到我们的学习圈来，正因为我不是211，985，只是个普通的本科生，英语不是特别好，数学不是特别好。所以我选择了前端。工作第六个年头了，我庆幸自己选择了这条路。767-273-102 秋裙。与大家分享一些学习方法，实战开发需要注意的细节。从零基础开始怎么样学好前端。都是一群有梦想的人，我们可能在不同的城市，但我们会一起结伴同行前端前端前端
CSS样式

然后分别为它们添加下面的CSS样式。

/* KEYFRAMES */
 
@keyframes spin {
  from {
    transform: rotate(0);
  }
  to{
    transform: rotate(359deg);
  }
}
 
@keyframes configure-clockwise {
  0% {
    transform: rotate(0);
  }
  25% {
    transform: rotate(90deg);
  }
  50% {
    transform: rotate(180deg);
  }
  75% {
    transform: rotate(270deg);
  }
  100% {
    transform: rotate(359deg);
  }
}
 
@keyframes configure-xclockwise {
  0% {
    transform: rotate(45deg);
  }
  25% {
    transform: rotate(-45deg);
  }
  50% {
    transform: rotate(-135deg);
  }
  75% {
    transform: rotate(-215deg);
  }
  100% {
    transform: rotate(-305deg);
  }
}
 
@keyframes pulse {
  from {
    opacity: 1;
    transform: scale(1);
  }
  to {
    opacity: .25;
    transform: scale(.75);
  }
}
 
/* GRID STYLING */
 
* {
  box-sizing: border-box;
}
 
body {
  min-height: 100vh;
  background-color: #37474f;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  align-items: flex-start;
}
 
.spinner-box {
  width: 300px;
  height: 300px;
  display: flex;
  justify-content: center;
  align-items: center;
  background-color: transparent;
}
 
/* SPINNING CIRCLE */
 
.circle-border {
  width: 150px;
  height: 150px;
  padding: 3px;
  display: flex;
  justify-content: center;
  align-items: center;
  border-radius: 50%;
  background: rgb(63,249,220);
  background: linear-gradient(0deg, rgba(63,249,220,0.1) 33%, rgba(63,249,220,1) 100%);
  animation: spin .8s linear 0s infinite;
}
 
.circle-core {
  width: 100%;
  height: 100%;
  background-color: #37474f;
  border-radius: 50%;
}
 
/* X-ROTATING BOXES */
 
.configure-border-1 {
  width: 115px;
  height: 115px;
  padding: 3px;
  position: absolute;
  display: flex;
  justify-content: center;
  align-items: center;
  background: #ffab91;
  animation: configure-clockwise 3s ease-in-out 0s infinite alternate;
}
 
.configure-border-2 {
  width: 115px;
  height: 115px;
  padding: 3px;
  left: -115px;
  display: flex;
  justify-content: center;
  align-items: center;
  background: rgb(63,249,220);
  transform: rotate(45deg);
  animation: configure-xclockwise 3s ease-in-out 0s infinite alternate;
}
 
.configure-core {
  width: 100%;
  height: 100%;
  background-color: #37474f;
}
 
/* PULSE BUBBLES */
 
.pulse-container {
  width: 120px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
 
.pulse-bubble {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background-color: #3ff9dc;
}
 
.pulse-bubble-1 {
    animation: pulse .4s ease 0s infinite alternate;
}
.pulse-bubble-2 {
    animation: pulse .4s ease .2s infinite alternate;
}
.pulse-bubble-3 {
    animation: pulse .4s ease .4s infinite alternate;
}
 
/* SOLAR SYSTEM */
 
.solar-system {
  width: 250px;
  height: 250px;
  display: flex;
  justify-content: center;
  align-items: center;
}
 
.orbit {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    border: 1px solid #ffffffa5;
    border-radius: 50%;
}
 
.earth-orbit {
    width: 165px;
    height: 165px;
  -webkit-animation: spin 12s linear 0s infinite;
}
 
.venus-orbit {
    width: 120px;
    height: 120px;
  -webkit-animation: spin 7.4s linear 0s infinite;
}
 
.mercury-orbit {
    width: 90px;
    height: 90px;
  -webkit-animation: spin 3s linear 0s infinite;
}
 
.planet {
    position: absolute;
    top: -5px;
  width: 10px;
  height: 10px;
    border-radius: 50%;
  background-color: #3ff9dc;
}
 
.sun {
    width: 35px;
    height: 35px;
    border-radius: 50%;
    background-color: #ffab91;
}