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AI solution for CSS coding question on BFE.dev
12. close button in CSS

To create a close button in CSS with lines for the cross, use the following code:

.close {
  position: relative;
  width: 30px; /* adjust width as needed */
  height: 30px; /* adjust height as needed */
  background-color: transparent;
  border: none;
  cursor: pointer;
}

.close:before,
.close:after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 75%;
  height: 2px;
  background-color: #aaa;
}

.close:before {
  transform: translate(-50%, -50%) rotate(45deg);
}

.close:after {
  transform: translate(-50%, -50%) rotate(-45deg);
}

In the HTML code, add the close class to the button element:

<button class="close"></button>

Adjust the width and height properties in the CSS code to change the size of the button as needed.