Diagonal shapes with CSS
4th July 2003
Information on Border Slants (via Paul Hammond). Border slants are the effect whereby diagonal lines can be created using pure CSS, by taking advantage of the fact that thick borders around a box meet at an angle. This article describes the effect in detail and shows how it can be used to achieve a number of interesting shapes, then goes on to show off with an impressive Valentine’s Day Heart. See also Tantek’s awesome pentagon site map and A Study of Regular Polygons.
More recent articles
- The Summer of Johann: prompt injections as far as the eye can see - 15th August 2025
- Open weight LLMs exhibit inconsistent performance across providers - 15th August 2025
- LLM 0.27, the annotated release notes: GPT-5 and improved tool calling - 11th August 2025