html - 向元素的选定 Angular 添加圆 Angular 边框

Question

我怎样才能用纯 CSS 构建这样的东西？

这是我到目前为止的进展:Fiddle

即使我继续添加额外的 span，我也在为如何获得那个圆 Angular 而苦苦挣扎。

---

代码:

body {
  background: #000;
}

.container {
  position: relative;
  width: 300px;
  height: 150px;
  margin: 10% auto;
}

.top-right {
  position: absolute;
  top: -10px;
  right: 0;
  width: 50px;
  height: 1px;
  background: white;
  border-radius: 5px;
}

.box {
  width: 100%;
  height: 100%;
  background: red;
  border-radius: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
}

h3 {
  color: white;
}

<div class="container">
  <span class="top-right"></span>
  <div class="box">
    <h3>Content</h3>
  </div>
</div>

Answer 1

您可以通过在 .box 中使用伪元素 ::before/::after 使用属性 border< 来实现这一点 和 border-radius

body {
  background: #000;
}
.container {
  width: 300px;
  height: 150px;
  margin: 3% auto 0 /* changed for demo */
}
h3 {
  color: white;
}
.box {
  width: 100%;
  height: 100%;
  background: red;
  border-radius: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}
.box::before,
.box::after {
  content: "";
  position: absolute;
  border: solid white;
  width: 50px;
  height: 50px;
}
.box::before {
  top: -15px;
  left: -15px;
  border-radius: 15px 0; /* top-left */
  border-width: 5px 0 0 5px;
}
.box::after {
  bottom: -15px;
  right: -15px;
  border-radius: 0 0 15px; /* bottom-right */
  border-width: 0 5px 5px 0;
}

<div class="container">
  <div class="box">
    <h3>Content</h3>
  </div>
</div>