chopped-off corners from a button with a solid border

Question

I want to cut two corners of a button with a 3px solid border and no background, like the example below, preferably with only CSS. I tried many options and searched the web, but no luck so far... Do you guys know a way to achieve this? Thanks for any response!

What I got so far is:

a.button{
    padding: 10px 18px;
    border: 3px solid $blue;
    text-transform: uppercase;
    font-size: 15px;
    border-top-left-radius: 15px;
    border-bottom-right-radius: 15px;
}

The problem is that this results in a radius corner, and I want the corners to be a straight cut.

Answer 1

This should help you get started.

You can refine it according to your needs.

.button {
  display: inline-block;
  text-transform: uppercase;
  text-decoration: none;
  padding: 10px 20px;
  border: 3px solid #3777BC;
  margin: 20px;
  position: relative;
  color: #3777BC;
  letter-spacing: 1px;
}
.button:before {
  content: '';
  width: 20px;
  height: 20px;
  background: #fff;
  border: 3px solid #3777BC;
  transform: rotate(45deg);
  position: absolute;
  border-top: 0;
  border-left: 0;
  border-bottom: 0;
  top: -12px;
  left: -13px;
}
.button:after {
  content: '';
  width: 20px;
  height: 20px;
  background: #fff;
  border: 3px solid #3777BC;
  transform: rotate(-132deg);
  position: absolute;
  border-top: 0;
  border-left: 0;
  border-bottom: 0;
  top: auto;
  right: -13px;
  bottom: -12px;
}

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