用css3实现惊艳面试官的背景即背景动画(高级附源码)

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我们传统的前端更多的是用javascript实现各种复杂动画,自从有了Css3 transition和animation以来,前端开发在动画这一块有了更高的自由度和格局,对动画的开发也越来越容易。这篇文章就让我们汇总一下使用Css3实现的各种特效。这篇文章参考《css揭秘》这本书,并作出了自己的总结,希望能让大家更有收获,也强烈推荐大家看看这本书,你值得拥有。

我们将学到

  • Css3
  • outline
  • radial-gradient
  • linear-gradient
  • box-shadow

程序员必读

Css3编码技巧

1.实现内部虚线边框

知识点:outline

核心代码

.dash-border{
  width: 200px;
  height: 100px;
  line-height: 100px;
  outline: 1px dashed #fff;
  outline-offset: -10px;
}

2.边框内圆角的实现

知识点:box-shadow

核心代码

.radius-border{
  margin-top: 20px;
  width: 180px;
  height: 80px;
  box-shadow: 0 0 0 10px gray;
}

3.实现条纹背景与进度条

知识点:linear-gradient,repeating-linear-gradient

核心代码

/* 上 */
background: linear-gradient(to right,#fb3 50%,#58a 0);
background-size: 40px 100%;
box-shadow: inset 0 0 3px #555;

/* 中 */
background: linear-gradient(45deg,#fb3 25%,#58a 0,#58a 50%,#fb3 0,#fb3 75%,#58a 0);
background-size: 40px 40px;

/* 下 (可以实现任意角度的渐变,45°时显示效果最好) */
background: repeating-linear-gradient(60deg,#fb3,#fb3 15px,#58a 0,#58a 30px);

4.复杂的背景图案

知识点:linear-gradient,repeating-linear-gradient,radial-gradient

由于第二个图会有复杂的随机动画,建议大家可以亲自尝试看看效果,核心代码

<style>
.bg-grid{
  margin-top: 20px;
  width: 200px;
  height: 200px;
  background-image: linear-gradient(rgba(255,255,255,1) 2px,transparent 0),
  linear-gradient(to right,rgba(255,255,255,1) 2px,transparent 0),
  linear-gradient(rgba(255,255,255,.2) 1px,transparent 0),
  linear-gradient(to right,rgba(255,255,255,.2) 1px,transparent 0);
  background-position: -50px -50px;
  background-size: 100px 100px,100px 100px, 100% 10px, 10px 100%;
}
.animate-grid{
  animation: move-grid 6s linear infinite;
}
@keyframes move-grid{
  0%{
    background-position: -50px -50px;
  }
  30%{
    background-position: -100px -100px;
  }
  60%{
    background-position: -100px -150px;
  }
  100%{
    background-position: -50px -50px;
  }
}
</style>
<div class="bg-grid black-theme"></div>
<div class="bg-grid black-theme animate-grid"></div>

红绿灯以及红路灯随机运动动画

利用css3多背景和position实现红绿灯和背景色块移动

核心代码

<style>
.bg-dot{
  margin-top: 20px;
  width: 200px;
  height: 50px;
  background-image: radial-gradient(circle,#0cf 15px,transparent),
                    radial-gradient(circle,red 15px,transparent),
                    radial-gradient(circle,yellow 15px,transparent),
                    radial-gradient(circle,green 15px,transparent);
  background-repeat: no-repeat;
  background-position: 0 0, 50px 0, 100px 0, 150px 0, 200px 0;
  background-size: 50px 50px;
}
.animate-dot{
  animation: move-dot 8s linear infinite;
}
.animate-dot2{
  animation: move-dot2 6s linear infinite;
}
@keyframes move-dot{
  0%{
    background-position: 0 0, 50px 0, 100px 0, 150px 0;
  }
  30%{
    background-position: 50px 0, 0 0, 100px 0, 150px 0;
  }
  60%{
    background-position: 50px 0, 100px 0, 0 0, 150px 0;
  }
  100%{
    background-position: 50px 0, 100px 0, 150px 0, 0 0;
  }
}
@keyframes move-dot2{
  0%{
    background-image: radial-gradient(circle,#0cf 15px,transparent),
                    radial-gradient(circle,gray 15px,transparent),
                    radial-gradient(circle,gray 15px,transparent),
                    radial-gradient(circle,gray 15px,transparent);
  }
  30%{
    background-image: radial-gradient(circle,gray 15px,transparent),
                    radial-gradient(circle,red 15px,transparent),
                    radial-gradient(circle,gray 15px,transparent),
                    radial-gradient(circle,gray 15px,transparent);
  }
  60%{
    background-image: radial-gradient(circle,gray 15px,transparent),
                    radial-gradient(circle,gray 15px,transparent),
                    radial-gradient(circle,yellow 15px,transparent),
                    radial-gradient(circle,gray 15px,transparent);
  }
  100%{
    background-image: radial-gradient(circle,gray 15px,transparent),
                    radial-gradient(circle,gray 15px,transparent),
                    radial-gradient(circle,gray 15px,transparent),
                    radial-gradient(circle,green 15px,transparent);
  }
}
</style>
<div class="bg-dot black-theme animate-dot"></div>
<div class="bg-dot black-theme animate-dot2"></div>

棋盘背景以及棋盘背景随机动画

利用背景渐变实现棋盘图案

核心代码

<style>
.bg-qi{
  margin-top: 20px;
  width: 200px;
  height: 200px;
  background-color: #eee;
  background-image: linear-gradient(45deg,rgba(0,0,0,.25) 25%,transparent 0,transparent 75%,rgba(0,0,0,.25) 0),
  linear-gradient(45deg,rgba(0,0,0,.25) 25%,transparent 0,transparent 75%,rgba(0,0,0,.25) 0);
  background-position: 0 0, 20px 20px;
  background-size: 40px 40px;
  box-shadow: 2px 2px 4px rgba(0,0,0,.4);
}

</style>
<div class="bg-qi black-theme"></div>

伪随机背景

利用背景渐变,keyframe动画,实现复杂的伪随机动画

核心代码

<style>
.bg-line-rand{
  margin-top: 20px;
  width: 480px;
  height: 60px;
  background-color: #eee;
  background-image: linear-gradient(90deg,#fb3 11px, transparent 0),
                    linear-gradient(90deg,#ab4 23px, transparent 0),
                    linear-gradient(90deg,#655 41px, transparent 0);
  background-size: 41px 100%, 61px 100%, 83px 100%;
  box-shadow: 2px 2px 4px rgba(0,0,0,.4);
}
.bg-dot-rand{
  margin-top: 20px;
  width: 200px;
  height: 200px;
  background-color: #eee;
  background-image: radial-gradient(circle,#fb3 5px, transparent 0),
                    radial-gradient(circle,#ab4 13px, transparent 0),
                    radial-gradient(circle,#655 31px, transparent 0);
  background-repeat: no-repeat;
  background-size: 101px 203px, 147px 60px, 373px 201px;
  box-shadow: 2px 2px 4px rgba(0,0,0,.4);
}
.animate1{
  animation: move 4s linear infinite;
}
.animate2{
  animation: move2 4s linear infinite;
}
@keyframes move{
  0%{
    background-position: 0 0, 0 0, 0 0;
  }
  50%{
    background-position: -10px 0, 20px 0, 30px 0;
  }
  100%{
    background-position: 0 0, 30px 0, 10px 0;
  }
}
@keyframes move2{
  0%{
    background-position: 0 0, 0 0, 0 0;
  }
  50%{
    background-position: -10px 30px, 20px 0, -40px 80px;
  }
  100%{
    background-position: 0 20px, 60px -20px, 10px 30px;
  }
}
</style>
<div class="bg-line-rand black-theme"></div>
<div class="bg-line-rand black-theme animate1"></div>
<div class="bg-dot-rand black-theme animate2"></div>

5.折角效果

知识点:linear-gradient

核心代码

<style>
.fold{
  margin-left: auto;
  margin-right: auto;
  margin-bottom: 20px;
  width: 200px;
  height: 80px;
  color: #fff;
  line-height: 80px;
  text-align: center;
  background: linear-gradient(to left bottom,transparent 50%,rgba(0,0,0,.5) 0) no-repeat 100% 0 / 2em 2em,
              linear-gradient(-135deg,transparent 1.4em,#06c 0);
}
.linear{
  background: linear-gradient(to left bottom,transparent 50%,rgba(0,0,0,.5)) no-repeat 100% 0 / 2em 2em,
              linear-gradient(-135deg,transparent 1.4em,#06c);
}
</style>
<div class="fold">折角效果哦</div>
<div class="fold linear">折角效果哦</div>

2.内阴影圆折角效果

核心代码

<style>
.fold-1{
  margin-left: auto;
  margin-right: auto;
  margin-bottom: 20px;
  position: relative;
  width: 200px;
  height: 80px;
  border-radius: .5em;
  color: #fff;
  line-height: 80px;
  text-align: center;
  background: linear-gradient(-150deg,transparent 1.5em, #58a 0);
}
.fold-1::before{
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  background: linear-gradient(to left bottom,transparent 50%,rgba(0,0,0,.2) 0,rgba(0,0,0,.4)) 100% 0 no-repeat;
  width: 1.73em;
  height: 3em;
  transform: translateY(-1.3em) rotate(-30deg);
  transform-origin: bottom right;
  border-bottom-left-radius: inherit;
  box-shadow: -.2em .2em .3em -.1em rgba(0,0,0,.15);
}

</style>
<div class="fold-1">折角效果哦</div>

6.自适应文本的条纹背景

知识点:linear-gradient,line-height,background-origin

核心代码

<style>
.stripe-bg{
  padding: .5em;
  line-height: 1.5em;
  background: beige;
  background-size: auto 3em;
  background-origin: content-box;
  background-image: linear-gradient(rgba(0,0,0,.2) 50%, transparent 0);
}
.stripe-bg > p{
  margin: 0;
}
</style>
<div class="stripe-bg">
  <p>hello you</p>
  <p>hello you</p>
  <p>hello you</p>
  <p>hello you</p>
  <p>hello you</p>
</div>

7.自定义的下划线实现

知识点linear-gridient

小伙伴们注意到了吗?默认的下划线会将文字穿过,而上面的不会呦!

核心代码

<style>
.my-line{
  line-height: 1.4em;
  background: linear-gradient(gray,gray) no-repeat;
  background-size: 100% 1px;
  background-position: 0 1.15em;
  text-shadow: .05em 0 #fff, -.05em 0 #fff;
}
</style>
<div class=""><span class="my-line">i have your big apple.you have a too? hi hi hi.</span></div>

最后

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  • 后台Node+Koa+redis+JsonSchema
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