Day 64: the revert-layer keyword
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It’s time to get me up to speed with modern CSS. There’s so much new in CSS that I know too little about. To change that I’ve started #100DaysOfMoreOrLessModernCSS. Why more or less modern CSS? Because some topics will be about cutting-edge features, while other stuff has been around for quite a while already, but I just have little to no experience with it.
With cascade layers comes a new CSS-wide property value, revert-layer.
You can use the revert-layer keyword to roll back the cascade to a value defined in a previous layer.
In the following example, the base layer defines a black color for the border. The theme layer sets the border color to fuchsia. In a print media query within the theme layer we revert the style back to the color in the base layer.
@layer base {
h2 {
--border-color: #000;
border: 4px solid var(--border-color);
}
}
@layer theme {
h2 {
--border-color: fuchsia;
}
@media print {
h2 {
--border-color: revert-layer;
}
}
}<h2>Sretan Božić!</h2>Sretan Božić!
If you try to print this page, you will see that the border-color of the <h2> is #000.
Further reading
- Day 37: cascade layers
- Day 40: unlayered styles
- Day 43: grouping layers
- Day 46: ordering layers
- Day 49: layering entire style sheets
- Day 52: multiple layer lists
- Day 55: anonymous layers
- Day 58: ordering nested layers
- Day 63: explicit defaulting with inherit, initial, unset, and revert
- Day 68: cascade layers and browser support
- Day 74: using !important in cascade layers
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Overview: 100 Days Of More Or Less Modern CSS