First try: style sheet

Ribbon effect

Second try: inline styles
Ribbon effect

Third try: table cells with inline styles
Ribbon effect

2018. febr. 8., csütörtök, 13.01.12 CET   –   2018. febr. 9., péntek, 14.45.30 CET

Ribbon by KZG

As of Chris Coyier's Ribbon, the first and second version is not suitable for email content, and probably does not work in MSIE 8 and bellow either. My code is as follows, with possible incompatibility = background: linear-gradient.
Box and border dimensions given in scalable element measurement (em) did not work in several Windows versions, the chosen 1.1ems have caused a gap between different element borders. I have changed border widths to pixel values.