:before和:after的作用就是在指定的元素内容（而不是元素本身）之前或者之后插入一个包含content属性指定内容的行内元素，最基本的用法如下：
#example:before { content: "#"; color: red;} #example:after { content: "$"; color: red;}这段代码会在#example元素内容之前插入一个'#'，以及在内容之后添加一个'$'，插入的行内元素是作为#example的子元素.效果为 #Here is the example content$ 需要注意的是如果没有content属性，伪类元素将没有任何作用。但是可以指定content为空，同时正如前面所说，插入的内容默认是一个行内元素，并且在HTML源代码中无法看到，这就是为什么称之为伪类元素的理由，所以也就无法通过DOM对其进行操作。
#example:before { content: ""; display: block; width: 100px; height: 100px;}最后附上2个:befroe 和：after的 例子①八卦图
<!doctype html><html><head> <title></title> <style> .yin-yang { width: 96px; height: 48px; background: #eee; border-color: red; border-style: solid; border-width: 2px 2px 50px 2px; border-radius: 100%; position: relative; } #yin-yang:before { content: ""; position: absolute; top: 50%; left: 0; background: #eee; border: 18px solid red; border-radius: 100%; width: 12px; height: 12px; } #yin-yang:after { content: ""; position: absolute; top: 50%; left: 50%; background: red; border: 18px solid #eee; border-radius: 100%; width: 12px; height: 12px; } </style></head><body> <div class="yin-yang" id="yin-yang"></div></body></html> ②
烤肉图
<!doctype html><html><head> <title></title> <meta charset="utf-8" /> <link rel="stylesheet" href="" media="screen" type="text/css" /> <style> :before, :after { content: ''; } .BBQ { border-radius: 50%/20% 70%; box-shadow: 40px 48px 0 #333, -32px -49.6px 0 #333, -40px 25.6px 0 #333, 28.8px -36.8px 0 #333, 8px 80px #333, -64px 72px #333, 88px 19.2px #333, -104px 25.6px #333, -88px -25.6px #333, -96px 104px #333, -40px 128px #333, 24px 128px #333, 80px 96px #333, -16px 40px 0 120px #C33, -16px 40px 0 140px #333; position: relative; width: 40px; height: 40px; margin: 100px auto; background: #333; } .BBQ:before, .BBQ:after { box-shadow: 18.4px 0 0 #999, 36.8px 0 0 #999, 55.2px 0 0 #999, 73.6px 0 0 #999, 92px 0 0 #999, 110.4px 0 0 #999, 128.8px 0 0 #999, 147.2px 0 0 #999, 165.6px 0 0 #999, 184px 0 0 #999, 202.4px 0 0 #999, 220.8px 0 0 #999, 239.2px 0 0 #999, 257.6px 0 0 #999; display: block; position: absolute; top: -90px; left: -130px; width: 5px; height: 300px; background: #999; } .BBQ:after { -ms-transform: rotate(90deg); -webkit-transform: rotate(90deg); transform: rotate(90deg); top: -220px; left: 0; } .BBQ .meat { border-radius: 50%/30% 70% 25% 50%; box-shadow: 0 0 0 6px rgba(255, 255, 255, 0.3) inset, 0 0 6px rgba(33, 33, 33, 0.3); position: absolute; top: 70px; left: 40px; width: 80px; height: 80px; background: #B45227; z-index: 1; } .BBQ .meat:before, .BBQ .meat:after { border-radius: 45%; box-shadow: 15px 0 0 0 rgba(33, 33, 33, 0.2), 30px 0 0 0 rgba(33, 33, 33, 0.2); position: absolute; display: block; width: 4px; height: 60%; background: rgba(33, 33, 33, 0.2); } .BBQ .meat:before { -ms-transform: rotate(30deg); -webkit-transform: rotate(30deg); transform: rotate(30deg); top: 9px; left: 24px; } .BBQ .meat:after { -ms-transform: rotate(-60deg); -webkit-transform: rotate(-60deg); transform: rotate(-60deg); top: 30px; left: 30px; } .BBQ .sausage { border-radius: 10px; box-shadow: -6px 0 8px 0 rgba(92, 0, 0, 0.8) inset, 2px 0 2px 0 rgba(33, 33, 33, 0.5), 0 0 5px rgba(33, 33, 33, 0.5); position: absolute; top: 60px; left: -52px; width: 25px; height: 100px; background: #A00; z-index: 1; } .BBQ .sausage:before { box-shadow: -1px 2px 2px 0 rgba(33, 33, 33, 0.5) inset; position: relative; top: 100%; display: block; margin: 0 auto; width: 5px; height: 30px; background: #F2E6CA; } .BBQ .sausage:after { border-radius: 0 25px 25px 0; filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=30); opacity: 0.3; box-shadow: 1px -1px 0 1px rgba(33, 0, 0, 0.7), 0 22px 0 0 #632121, 1px 21px 0 1px rgba(33, 0, 0, 0.7), 0 44px 0 0 #632121, 1px 43px 0 1px rgba(33, 0, 0, 0.7); position: absolute; top: 22%; left: 0; display: block; width: 55%; height: 7px; background: #632121; } .BBQ .corn { border-radius: 9px; box-shadow: 4px -2px 4px rgba(99, 33, 99, 0.3) inset, -10px -2px 10px rgba(99, 33, 99, 0.5) inset, 0 0 5px rgba(33, 33, 33, 0.3); position: absolute; top: 60px; left: -12px; width: 35px; height: 100px; background: #F2D204; z-index: 1; } .BBQ .corn:before { box-shadow: -1px 2px 2px 0 rgba(33, 33, 33, 0.5) inset; position: relative; top: 100%; display: block; margin: 0 auto; width: 5px; height: 30px; background: #F2E6CA; } .BBQ .corn:after { border-radius: 2px; filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=20); opacity: 0.2; box-shadow: 1px 1px 0 rgba(33, 33, 33, 0.3), 8px 0 0 #F2D204, 9px 1px 0 rgba(33, 33, 33, 0.5), 16px 0 0 #F2D204, 17px 1px 0 rgba(33, 33, 33, 0.5), 24px 0 0 #F2D204, 25px 1px 0 rgba(33, 33, 33, 0.2), 0 8px 0 #F2D204, 1px 9px 0 rgba(33, 33, 33, 0.3), 8px 8px 0 #F2D204, 9px 9px 0 rgba(33, 33, 33, 0.5), 16px 8px 0 #F2D204, 17px 9px 0 rgba(33, 33, 33, 0.5), 24px 8px 0 #F2D204, 25px 9px 0 rgba(33, 33, 33, 0.2), 0 16px 0 #F2D204, 1px 17px 0 rgba(33, 33, 33, 0.3), 8px 16px 0 #F2D204, 9px 17px 0 rgba(33, 33, 33, 0.5), 16px 16px 0 #F2D204, 17px 17px 0 rgba(33, 33, 33, 0.5), 24px 16px 0 #F2D204, 25px 17px 0 rgba(33, 33, 33, 0.2), 0 24px 0 #F2D204, 1px 25px 0 rgba(33, 33, 33, 0.3), 8px 24px 0 #F2D204, 9px 25px 0 rgba(33, 33, 33, 0.5), 16px 24px 0 #F2D204, 17px 25px 0 rgba(33, 33, 33, 0.5), 24px 24px 0 #F2D204, 25px 25px 0 rgba(33, 33, 33, 0.2), 0 32px 0 #F2D204, 1px 33px 0 rgba(33, 33, 33, 0.3), 8px 32px 0 #F2D204, 9px 33px 0 rgba(33, 33, 33, 0.5), 16px 32px 0 #F2D204, 17px 33px 0 rgba(33, 33, 33, 0.5), 24px 32px 0 #F2D204, 25px 33px 0 rgba(33, 33, 33, 0.2), 0 40px 0 #F2D204, 1px 41px 0 rgba(33, 33, 33, 0.3), 8px 40px 0 #F2D204, 9px 41px 0 rgba(33, 33, 33, 0.5), 16px 40px 0 #F2D204, 17px 41px 0 rgba(33, 33, 33, 0.5), 24px 40px 0 #F2D204, 25px 41px 0 rgba(33, 33, 33, 0.2), 0 48px 0 #F2D204, 1px 49px 0 rgba(33, 33, 33, 0.3), 8px 48px 0 #F2D204, 9px 49px 0 rgba(33, 33, 33, 0.5), 16px 48px 0 #F2D204, 17px 49px 0 rgba(33, 33, 33, 0.5), 24px 48px 0 #F2D204, 25px 49px 0 rgba(33, 33, 33, 0.2), 0 56px 0 #F2D204, 1px 57px 0 rgba(33, 33, 33, 0.3), 8px 56px 0 #F2D204, 9px 57px 0 rgba(33, 33, 33, 0.5), 16px 56px 0 #F2D204, 17px 57px 0 rgba(33, 33, 33, 0.5), 24px 56px 0 #F2D204, 25px 57px 0 rgba(33, 33, 33, 0.2), 0 64px 0 #F2D204, 1px 65px 0 rgba(33, 33, 33, 0.3), 8px 64px 0 #F2D204, 9px 65px 0 rgba(33, 33, 33, 0.5), 16px 64px 0 #F2D204, 17px 65px 0 rgba(33, 33, 33, 0.5), 24px 64px 0 #F2D204, 25px 65px 0 rgba(33, 33, 33, 0.2), 0 72px 0 #F2D204, 1px 73px 0 rgba(33, 33, 33, 0.3), 8px 72px 0 #F2D204, 9px 73px 0 rgba(33, 33, 33, 0.5), 16px 72px 0 #F2D204, 17px 73px 0 rgba(33, 33, 33, 0.5), 24px 72px 0 #F2D204, 25px 73px 0 rgba(33, 33, 33, 0.2), 0 80px 0 #F2D204, 1px 81px 0 rgba(33, 33, 33, 0.3), 8px 80px 0 #F2D204, 9px 81px 0 rgba(33, 33, 33, 0.5), 16px 80px 0 #F2D204, 17px 81px 0 rgba(33, 33, 33, 0.5), 24px 80px 0 #F2D204, 25px 81px 0 rgba(33, 33, 33, 0.2), 0 88px 0 #F2D204, 1px 89px 0 rgba(33, 33, 33, 0.3), 8px 88px 0 #F2D204, 9px 89px 0 rgba(33, 33, 33, 0.5), 16px 88px 0 #F2D204, 17px 89px 0 rgba(33, 33, 33, 0.5), 24px 88px 0 #F2D204, 25px 89px 0 rgba(33, 33, 33, 0.2); position: absolute; top: 2px; left: 0; display: block; width: 22%; height: 6%; } .BBQ .waterbamboo { background-image: -webkit-linear-gradient(bottom, #ffffff 0%, #96c56f 30%); background-image: linear-gradient(to top, #ffffff 0%, #96c56f 30%); box-shadow: -5px 0 5px rgba(33, 33, 33, 0.4) inset, 0 0 3px rgba(33, 33, 33, 0.3); border-radius: 70%/60% 10% 0 0; position: absolute; top: 30px; left: -95px; display: block; width: 25px; height: 170px; border-top: 0; z-index: 1; } .BBQ .waterbamboo:before { background-image: -webkit-linear-gradient(bottom, rgba(0, 0, 0, 0) 0%, #428c42 50%); background-image: linear-gradient(to top, rgba(0, 0, 0, 0) 0%, #428c42 50%); box-shadow: -1px -1px 1px 0 rgba(33, 66, 33, 0.2); border-radius: 35% 15% 0 0/70% 30% 0 0; position: absolute; top: -5px; right: 0; display: block; width: 16px; height: 70%; } .BBQ .shrimp { border-radius: 60%/30% 40% 10% 70%; background-image: -webkit-radial-gradient(circle at center right, rgba(0, 0, 0, 0) 67%, #cc4a04 68%, #ef6921 74%, #ef6921 85%, rgba(33, 33, 33, 0.2) 86%, rgba(0, 0, 0, 0) 90%); background-image: radial-gradient(circle at center right, rgba(0, 0, 0, 0) 67%, #cc4a04 68%, #ef6921 74%, #ef6921 85%, rgba(33, 33, 33, 0.2) 86%, rgba(0, 0, 0, 0) 90%); position: absolute; top: -35px; left: -10px; display: block; width: 86px; height: 70px; z-index: 1; } .BBQ .shrimp:before { -ms-transform: rotate(24deg); -webkit-transform: rotate(24deg); transform: rotate(24deg); border-radius: 85% 85% 50% 50%/120% 120% 50% 50%; box-shadow: 1px -35px 0 -7px #EF6921, 0 -36px 1px -7px rgba(33, 33, 33, 0.2), 5px -23px 0 -8px #EF6921, 5px -23px 1px -7px rgba(33, 33, 33, 0.2), 0 -2px 0 0 rgba(222, 222, 222, 0.3) inset, -2px 1px 2px rgba(33, 33, 33, 0.2); position: absolute; top: -24px; left: 15px; display: block; width: 18px; height: 45px; background: #EF6921; } .BBQ .shrimp:after { border-radius: 50%; background-image: -webkit-radial-gradient(circle at top center, #ef6921 35%, rgba(0, 0, 0, 0) 36%), -webkit-radial-gradient(circle at center left, #ef6921 27%, #cc4a04 37%, rgba(0, 0, 0, 0) 38%); background-image: -webkit-radial-gradient(top center, circle, #ef6921 35%, rgba(0, 0, 0, 0) 36%), -webkit-radial-gradient(circle at center left, #ef6921 27%, #cc4a04 37%, rgba(0, 0, 0, 0) 38%); background-image: radial-gradient(circle at top center, #ef6921 35%, rgba(0, 0, 0, 0) 36%), radial-gradient(circle at center left, #ef6921 27%, #cc4a04 37%, rgba(0, 0, 0, 0) 38%); box-shadow: -13px -86px 0 -9px rgba(222, 222, 222, 0.5), -14px -85px 0 -7px #212121; position: absolute; top: 60px; left: 25px; display: block; width: 22px; height: 22px; } .BBQ .clams { border-radius: 10px 30px 10px 50px; background-image: -webkit-radial-gradient(circle at top right, #c8c8c8 22%, #827909 30%, #212121 35%, #212121 50%, #665a07 65%, #827909 70%, #c8c8c8 72%, #665a07 75%); background-image: -webkit-radial-gradient(top right, circle, #c8c8c8 22%, #827909 30%, #212121 35%, #212121 50%, #665a07 65%, #827909 70%, #c8c8c8 72%, #665a07 75%); background-image: radial-gradient(circle at top right, #c8c8c8 22%, #827909 30%, #212121 35%, #212121 50%, #665a07 65%, #827909 70%, #c8c8c8 72%, #665a07 75%); box-shadow: 0 0 5px rgba(33, 33, 33, 0.3) inset, -1px 1px 5px rgba(33, 33, 33, 0.3); position: absolute; top: -58px; left: -80px; width: 40px; height: 40px; display: block; z-index: 1; } .BBQ .clams:after { border-radius: 10px 30px 10px 50px; background-image: -webkit-radial-gradient(circle at top right, #c8c8c8 22%, #827909 30%, #212121 35%, #212121 50%, #665a07 65%, #827909 70%, #c8c8c8 72%, #665a07 75%); background-image: radial-gradient(circle at top right, #c8c8c8 22%, #827909 30%, #212121 35%, #212121 50%, #665a07 65%, #827909 70%, #c8c8c8 72%, #665a07 75%); box-shadow: 0 0 5px rgba(33, 33, 33, 0.3) inset, -1px 1px 5px rgba(33, 33, 33, 0.3); display: block; position: absolute; top: 130%; left: 40%; width: 100%; height: 100%; } .BBQ .greenpepper { -ms-transform: rotate(180deg); -webkit-transform: rotate(180deg); transform: rotate(180deg); box-shadow: -1px 1px 2px 0 rgba(33, 33, 33, 0.5) inset; position: absolute; top: -60px; left: 75px; width: 5px; height: 120px; background: #F2E6CA; z-index: 1; } .BBQ .greenpepper:before, .BBQ .greenpepper:after { border-radius: 30% 40%/10% 20%; background-image: -webkit-linear-gradient(45deg, rgba(0, 0, 0, 0) 20%, rgba(33, 99, 33, 0.3) 50%, rgba(0, 0, 0, 0) 75%), -webkit-linear-gradient(330deg, rgba(0, 0, 0, 0) 0%, rgba(33, 120, 33, 0.6) 40%, rgba(0, 0, 0, 0) 65%, rgba(33, 99, 33, 0.5) 100%), -webkit-linear-gradient(45deg, #299a0b 45%, rgba(33, 99, 33, 0.3) 55%, #299a0b 75%), -webkit-linear-gradient(bottom, #299a0b 0%, #299a0b 100%); background-image: linear-gradient(45deg, rgba(0, 0, 0, 0) 20%, rgba(33, 99, 33, 0.3) 50%, rgba(0, 0, 0, 0) 75%), linear-gradient(120deg, rgba(0, 0, 0, 0) 0%, rgba(33, 120, 33, 0.6) 40%, rgba(0, 0, 0, 0) 65%, rgba(33, 99, 33, 0.5) 100%), linear-gradient(45deg, #299a0b 45%, rgba(33, 99, 33, 0.3) 55%, #299a0b 75%), linear-gradient(to top, #299a0b 0%, #299a0b 100%); box-shadow: 2px 2px 1px rgba(33, 33, 33, 0.3) inset, 0 0 3px rgba(33, 33, 33, 0.3); position: relative; display: block; left: -25px; margin-top: 6px; width: 50px; height: 35px; } .BBQ .smoke { border-radius: 50%; -webkit-animation: roastSmoke 5s ease-in-out infinite; animation: roastSmoke 5s ease-in-out infinite; background-image: -webkit-radial-gradient(ellipse at center center, rgba(33, 33, 33, 0.3) 0%, rgba(0, 0, 0, 0) 50%); background-image: -webkit-radial-gradient(center center, ellipse, rgba(33, 33, 33, 0.3) 0%, rgba(0, 0, 0, 0) 50%); background-image: radial-gradient(ellipse at center center, rgba(33, 33, 33, 0.3) 0%, rgba(0, 0, 0, 0) 50%); position: absolute; top: 0; left: 0; width: 100px; height: 60px; z-index: 2; } .BBQ .smoke:before { border-radius: 50%; -ms-transform: scale(1.6); -webkit-transform: scale(1.6); transform: scale(1.6); background-image: -webkit-radial-gradient(ellipse at center center, rgba(33, 33, 33, 0.3) 0%, rgba(0, 0, 0, 0) 50%); background-image: -webkit-radial-gradient(center center, ellipse, rgba(33, 33, 33, 0.3) 0%, rgba(0, 0, 0, 0) 50%); background-image: radial-gradient(ellipse at center center, rgba(33, 33, 33, 0.3) 0%, rgba(0, 0, 0, 0) 50%); position: absolute; top: -90px; left: 0; display: block; width: 100px; height: 60px; } @-webkit-keyframes roastSmoke { 0% { -ms-transform: scale(0.2) translateY(0); -webkit-transform: scale(0.2) translateY(0); transform: scale(0.2) translateY(0); filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=0); opacity: 0; } 30% { filter: progid:DXImageTransform.Microsoft.Alpha(enabled=false); opacity: 1; } 100% { -ms-transform: scale(1) translateY(-200px); -webkit-transform: scale(1) translateY(-200px); transform: scale(1) translateY(-200px); filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=0); opacity: 0; } } @keyframes roastSmoke { 0% { -ms-transform: scale(0.2) translateY(0); -webkit-transform: scale(0.2) translateY(0); transform: scale(0.2) translateY(0); filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=0); opacity: 0; } 30% { filter: progid:DXImageTransform.Microsoft.Alpha(enabled=false); opacity: 1; } 100% { -ms-transform: scale(1) translateY(-200px); -webkit-transform: scale(1) translateY(-200px); transform: scale(1) translateY(-200px); filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=0); opacity: 0; } } </style></head><body> <div class="BBQ"> <div class="meat"></div> <div class="sausage"></div> <div class="corn"></div> <div class="waterbamboo"></div> <div class="shrimp"></div> <div class="clams"></div> <div class="greenpepper"></div> <div class="smoke"></div> </div></body></html> ③
古典磁带
html文件
<!DOCTYPE html><html><head> <title>demo</title> <link rel="stylesheet" type="text/css" href="demo.css" /> <!--引用外部样式-->> <style></style></head><body style="background-color:#8b392e;"> <div class="cassette"> <div class="screws"> <div class="screw"> <div class="screw-inner"></div> </div> <div class="screw"> <div class="screw-inner"></div> </div> <div class="screw"> <div class="screw-inner"></div> </div> <div class="screw"> <div class="screw-inner"></div> </div> </div> <div class="outer-sticker"> <div class="sticker"> <div class="sticker-header"> <!-- /.sticker-header statr --> <div class="side">A</div> <div class="notes"> <!--A右边的3根线 --> <hr /> <hr /> <hr /> </div> </div><!-- /.sticker-header end --> <div class="sticker-center"> <!-- /.sticker-center statr--> <div class="stripe-a"></div> <!--褐色和蓝色的粗条纹，夹住2个小圆孔--> <div class="stripe-b"></div> <div class="cassete-center"> <div class="circle"> <!--左边的小圆孔--> <i></i> <!--6个小指针--> <i></i> <i></i> <i></i> <i></i> <i></i> </div> <div class="circle"> <!--右边的小圆孔--> <i></i> <i></i> <i></i> <i></i> <i></i> <i></i> </div> <div class="window"> <div class="reel"></div> <div class="reel"></div> </div> </div> </div> <!-- /.sticker-center end--> <div class="sticker-bottom"> <hr> <h5 id="音乐播放器">音乐播放器</h5> <hr> </div> <!-- /.sticker-bottom--> </div> <!-- /.sticker --> </div> <!-- /.outer-sticker --> </div> <!-- /.cassette --> <script> var box = new Date(0); alert(box); </script></body></html>
css文件
.cassette { position: relative; margin: 70px auto; background-color: #d55e40; border-radius: 20px; width: 534px; height: 335px; } .cassette:before { position: absolute; content: ""; z-index: 50; bottom: 20px; left: -3px; height: 90px; border-right: #d55e40 solid 5px; border-top: transparent solid 10px; border-bottom: transparent solid 10px; } .cassette:after { position: absolute; content: ""; z-index: 50; bottom: 20px; right: -3px; height: 90px; border-left: #d55e40 solid 5px; border-top: transparent solid 10px; border-bottom: transparent solid 10px; } .screw { position: absolute; display: block; width: 22px; height: 22px; background: #8b392e; border-radius: 50%; } .screw-inner { position: absolute; display: block; width: 16px; height: 16px; border-radius: 50%; top: 3px; left: 3px; transform: rotate(50deg); } .screw-inner:before, .screw-inner:after { content: ""; position: absolute; z-index: 2; background: #449ba2; width: 5px; border-radius: 2px; } .screw-inner:before { left: 50%; width: 40%; margin-left: -20%; height: 100%; } .screw-inner:after { top: 50%; height: 40%; margin-top: -20%; width: 100%; } .screws .screw:nth-child(1) { top: 5px; left: 10px; } .screws .screw:nth-child(2) { top: 5px; right: 10px; } .screws .screw:nth-child(3) { left: 10px; bottom: 5px; } .screws .screw:nth-child(4) { right: 10px; bottom: 5px; } .outer-sticker { background: #8b392e; width: 474px; height: 210px; position: relative; left: 50%; margin-left: -237px; border-radius: 16px; position: relative; margin-top: 25px; display: inline-block; } .sticker { background: #f3ae53; margin: 0 auto; width: 466px; height: 200px; border-radius: 16px; position: relative; margin-top: 5px; } .sticker-header { float: left; padding: 10px 20px 0px; width: 100%; } .sticker-header .side { font-weight: 700; font-size: 30px; color: #f3ae53; padding: 0 5px 1px; line-height: 32px; margin-top: 10px; background: #d55e40; float: left; -moz-border-radius: 5px; -webkit-border-radius: 5px; border-radius: 5px; } .sticker-header .notes { float: left; margin-left: 15px; width: 374px; } .sticker-header .notes hr { border: 0; height: 3px; background: #756046; margin-bottom: 15px; } .sticker-center { position:relative; display:inline-block; width:100%; } .sticker-center .stripe-a { background: #8b392e; display: inline-block; width: 100%; height: 30px; } .sticker-center .stripe-b { background: #449ba2; display: inline-block; width: 100%; height: 30px; margin-top: 30px; } .sticker-center .cassete-center { background: #d55e40; margin: 0 auto; width: 318px; height: 92px; -moz-border-radius: 16px; -webkit-border-radius: 16px; border-radius: 16px; position: absolute; top: 0; left: 50%; margin-left: -159px; } .sticker-center .cassete-center .circle { border-radius: 50%; width: 65px; height: 65px; background: #fff; position: absolute; top: 12px; -moz-animation: spin 0.8s infinite linear; -webkit-animation: spin 0.8s infinite linear; animation: spin 0.8s infinite linear; } .sticker-center .cassete-center .circle:nth-child(1) { left: 15px; } .sticker-center .cassete-center .circle:nth-child(2) { right: 15px; } .sticker-center .cassete-center .circle i { display: block; position: absolute; width: 5%; height: 55%; left: 45%; top: -5%; border-top: solid 15px #d55e40; transform-origin: 55% 70%; /*旋转原点的位置，也就是O点的位置哦*/ z-index: 999; } .sticker-center .cassete-center .circle i:nth-child(1) { transform: rotate(30deg); } .sticker-center .cassete-center .circle i:nth-child(2) { transform: rotate(90deg); } .sticker-center .cassete-center .circle i:nth-child(3) { transform: rotate(150deg); } .sticker-center .cassete-center .circle i:nth-child(4) { transform: rotate(210deg); } .sticker-center .cassete-center .circle i:nth-child(5) { transform: rotate(270deg); } .sticker-center .cassete-center .circle i:nth-child(6) { transform: rotate(330deg); } .sticker-center .cassete-center .window { position: absolute; overflow: hidden; background: white; width: 122px; height: 60px; left: 50%; margin-left: -61px; margin-top: 15px; -moz-border-radius: 5px; -webkit-border-radius: 5px; border-radius: 5px; } .sticker-center .cassete-center .window .reel { border-radius: 50%; width: 190px; height: 190px; background: #8b392e; position: absolute; top: -60px; -moz-animation: spin 0.8s infinite linear; -webkit-animation: spin 0.8s infinite linear; animation: spin 0.8s infinite linear; } .sticker-center .cassete-center .window .reel:nth-child(1) { left: -150px; } .sticker-center .cassete-center .window .reel:nth-child(2) { right: -150px; } @-webkit-keyframes spin { 0% { -webkit-transform: rotate(0deg); transform: rotate(0deg); } 100% { -webkit-transform: rotate(180deg); transform: rotate(180deg); } } .sticker-bottom { margin: 5px 5px; overflow: auto; } .sticker-bottom hr { border: 0; height: 3px; background: #363844; width: 170px; } .sticker-bottom hr:nth-child(1) { float: left; } .sticker-bottom hr:nth-child(3) { float: right; } .sticker-bottom h5 { font-size: 12px; float: left; line-height: 19px; padding-left: 27px; margin:0px; } 部分代码摘自
http://www.hulufei.com/post/about-before-and-after-pseudo-element
http://www.html5tricks.com/
初次写博文，都是拿别人的过来自己学习的。
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