在三角形元素上添加边框

Question

我想在三角形周围创建一个边框.到目前为止我有这个:

的jsfiddle

.myDiv {
  width: 300px;
  padding: 15px;
  text-align: right;
  background-color: lightblue;
  position: relative;
  border: 1px solid black;
}
.myDiv::before {
  content: "";
  position: absolute;
  bottom: -20px;
  right: 20px;
  border-right: 20px solid lightblue;
  border-bottom: 20px solid transparent;
}

<div class="myDiv">Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco</div>

但我无法为before元素添加边框.如何在底部伸出的部分周围添加边框('before`元素)？

(我看到了这个问题,但我不能对此应用相同的原理,因为它的形状不同.)

Answer 1

尝试添加::after更多border-width不同位置的底部和右侧,它的工作非常好.不要忘了更改border-color,以black低下来z-index的-1.

例:

.myDiv {
  width: 300px;
  padding: 15px;
  text-align: right;
  background-color: lightblue;
  position: relative;
  border: 1px solid black;
}

.myDiv::before {
  content: "";
  position: absolute;
  bottom: -20px;
  right: 20px;
  border-right: 20px solid lightblue;
  border-bottom: 20px solid transparent;
}

.myDiv::after {
  z-index:-1;
  content: "";
  position: absolute;
  width: 0;
  height: 0;
  bottom: -22px;
  right: 19px;
  border-right: 21px solid black;
  border-bottom: 21px solid transparent;
}

<div class="myDiv">Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco</div>

小提琴演示