css - 边界半径向内 flex ？

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CSS shape with inset curve and transparent background
                                
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                                2年前关闭。
            
                    
如何使边框向内弯曲而不是向外弯曲？

例如-这向外弯曲：

header {
  position: relative;
  height: 300px;
  background-image: linear-gradient(#ff9d2f, #ff6126);
  border-bottom-left-radius: 50% 20%;
  border-bottom-right-radius: 50% 20%;
}

h1 {
  margin: 0;
  padding: 100px 0;
  font: 44px "Arial";
  text-align: center;
}

header h1 {
  color: white;
}

<header>
  <h1>Header Content</h1>
</header>

<section>
  <h1>Section Content</h1>
</section>

我希望它向内弯曲，有可能吗？

最佳答案

像下面的例子

header {
  position: relative;
  height: 300px;
  background-image: linear-gradient(#ff9d2f, #ff6126);
}

h1 {
  margin: 0;
  padding: 100px 0;
  font: 44px "Arial";
  text-align: center;
}

header h1 {
  color: white;
}

header:after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  height: 30%;
  width: 100%;
  background: #fff;
  border-top-left-radius: 50% 20%;
  border-top-right-radius: 50% 20%;
  user-select: none;
}

<header>
  <h1>Header Content</h1>
</header>

<section>
  <h1>Section Content</h1>
</section>