| <!DOCTYPE html> | |
| <html> | |
| <head> | |
| <style> | |
| .box { | |
| width: 200px; | |
| height: 200px; | |
| background-color: green; | |
| filter: url(#sharpen); | |
| } | |
| </style> | |
| </head> | |
| <body> | |
| <svg style="display:none;" xmlns="http://www.w3.org/2000/svg" version="1.1"> | |
| <defs> | |
| <filter id="sharpen"> | |
| <feConvolveMatrix order="3 3" preserveAlpha="true" kernelMatrix="0 0 0 0 1 0 0 0 0" /> | |
| </filter> | |
| </defs> | |
| </svg> | |
| <div class="box"></div> | |
| </body> | |
| </html> |