CSS: “padding-left”: X negative values are not allowed.

A padding-left declaration has a negative value, and padding can't be less than zero.

Left padding is the space between an element's left border and its content, so CSS only accepts zero or a positive length or percentage for it. A browser drops a padding-left declaration with a negative value, and the element keeps whatever left padding it gets from other rules. On a list, that means the default indentation stays where it was.

To fix the error, change the value to 0 or a positive length. Setting padding-left: 0 removes the indentation a list gets by default. If the content has to move past the left edge of its container, use a negative margin-left, which CSS allows. The padding shorthand and the other side properties follow the same rule, and each one has its own message.

Invalid example

<ul class="links" style="padding-left: -20px;">
  <li>First link</li>
  <li>Second link</li>
</ul>

Valid example

<ul class="links" style="padding-left: 0;">
  <li>First link</li>
  <li>Second link</li>
</ul>

Learn more:

MDN Reference

MDN Web Docs: padding-left

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MDN Reference

MDN Web Docs: margin-left

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