如何将'div'塑造为CSS的旗帜

Question

我想在网站上的一些元素上添加标签,并设计一个标签,底部是倒V形切口的旗帜.

到目前为止我有这个:

HTML

<div class="css-shapes"></div>

CSS

.css-shapes{
    border-left: 99px solid #f00fff;
    border-right: 99px solid #f00fff;
    border-bottom: 39px solid transparent;
}

http://jsfiddle.net/yhexkm4u/2/

但是,我需要背景是白色的,并且在紫色和1px的这个形状周围.我试图在这个内部装入相同形状的白色,但是一切都变得混乱,并没有按预期进行.

也许这是一种错误的方法,但我希望最终得到的标签看起来像这样:

Answer 1

使用CSS:

您可以在伪元素上使用CSS变换来创建底部带有透明倒三角形的背景:

body{background:url('http://lorempixel.com/image_output/food-q-c-640-480-1.jpg');background-size:cover;}
p{
  position: relative;
  width: 150px; height: 150px;
  overflow: hidden;
  border-top:3px solid #EF0EFE;
}
p:before, p:after{
  content: '';
  position: absolute;
  top: -3px;
  height: 100%; width: 50%;
  z-index: -1;
  border:2px solid #EF0EFE;
  box-sizing:border-box;
}
p:before{
  left: 0;  
  transform-origin: 0 0;
  transform: skewY(-20deg);
  border-width:0 0 4px 3px;
}
p:after{
  right: 0;
  transform-origin: 100% 0;
  transform: skewY(20deg);
  border-width:0 3px 4px 0;
}

<p>Some text ... </p>

请注意,您需要在transform和transform-origin属性上添加供应商前缀以最大化浏览器支持.有关更多信息,请参阅canIuse.

随着SVG

另一种方法是使用带有多边形元素的内联SVG:

body{background: url('http://lorempixel.com/image_output/food-q-c-640-480-1.jpg');background-size: cover;}
div{position: relative;width: 100px; height: 150px;}
svg{position: absolute;width: 100%;height: 100%;z-index: -1;}

<div>
  <svg viewbox="-1.5 -1.5 103 153">
    <polygon points="100 0, 100 100, 50 85, 0 100, 0 0" fill="transparent" stroke-width="3" stroke="#ef0efe"/>
  </svg>
  <p>Some text ... </p>
</div>

Answer 2

这是一个稍微不同的方法,使用伪元素和变换旋转来创建如下所示的轮廓横幅:

• 这个有角度的形状是用position: absolute伪元素创建的,:before并且:after:

• 超出部分与overflow: hidden父母一起切断以形成我们的横幅:

• 创建轮廓box-shadow,通过拉动/推动x轴46px防止两个角度重叠 -box-shadow: 46px 0 0 3px #000

完整的例子

div {
  height: 100px;
  width: 100px;
  margin: 100px auto;
  position: relative;
  overflow: hidden;
  border: solid 3px #000;
  border-bottom: none;
  text-align: center;
}
div:before,
div:after {
  content: '';
  display: block;
  height: 100%;
  width: 200%;
  transform: rotate(20deg);
  box-shadow: 46px 0 0 3px #000;
  position: absolute;
  top: 1px;
  right: -120%;
}
div:after {
  transform: rotate(-20deg);
  left: -120%;
  box-shadow: -46px 0 0 3px #000;
}

<div>Text</div>

Answer 3

从 CSS-SHAPES 中窃取

#flag {
  width: 110px;
  height: 56px;
  padding-top: 15px;
  position: relative;
  background: red;
  color: white;
  font-size: 11px;
  letter-spacing: 0.2em;
  text-align: center;
  text-transform: uppercase;
}
#flag:after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 0;
  border-bottom: 13px solid #eee;
  border-left: 55px solid transparent;
  border-right: 55px solid transparent;
}

演示：

#flag {
  width: 110px;
  height: 56px;
  padding-top: 15px;
  position: relative;
  background: red;
  color: white;
  font-size: 11px;
  letter-spacing: 0.2em;
  text-align: center;
  text-transform: uppercase;
}
#flag:after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 0;
  border-bottom: 13px solid #eee;
  border-left: 55px solid transparent;
  border-right: 55px solid transparent;
}

#flag {
  width: 110px;
  height: 56px;
  padding-top: 15px;
  position: relative;
  background: red;
  color: white;
  font-size: 11px;
  letter-spacing: 0.2em;
  text-align: center;
  text-transform: uppercase;
}
#flag:after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 0;
  border-bottom: 13px solid #eee;
  border-left: 55px solid transparent;
  border-right: 55px solid transparent;
}
          

我的方法

我的方法使用倾斜元素，并允许您根据需要快速定位它们。

<div id="flag"></div>

div {
  height: 100px;
  width: 100px;
  position: relative;
  border-left: 10px solid tomato;
  border-top: 10px solid tomato;
  border-right: 10px solid tomato;
  text-align: center;
  line-height: 100px;
  font-size: 30px;
}
div:before {
  content: "";
  position: absolute;
  height: 50%;
  width: 50%;
  left: -10px; /*width of border*/
  bottom: -30px;
  z-index: -2;
  -webkit-transform: skewY(-20deg);
  transform: skewY(-20deg);
  border-bottom: 10px solid tomato;
  border-left: 10px solid tomato;
}
div:after {
  content: "";
  position: absolute;
  height: 50%;
  width: 50%;
  right: -10px; /*width of border*/
  bottom: -30px;
  z-index: -2;
  -webkit-transform: skewY(20deg);
  transform: skewY(20deg);
  border-bottom: 10px solid tomato;
  border-right: 10px solid tomato;
}
div:hover, div:hover:before, div:hover:after{
  background:lightgray;
  }