10 NEW CSS Features You Need To Know For 2026

CSS is getting way more powerful than most people realize. From custom functions and conditionals to zero-JS carousels and scroll logic, here are 10 features you should know for 2026.

🔗 Relevant Links
corner-shape: https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties/corner-shape
shape function: https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values/basic-shape/shape
Custom Select: https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/Customizable_select
Scroll Markers: https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors/::scroll-marker
Scroll State: https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Conditional_rules/Container_scroll-state_queries
Text Box: https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties/text-box
Sibling Index: https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values/sibling-index
if() functions: https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values/if
Custom Functions: https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Custom_functions_and_mixins/Using_custom_functions



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📌 Chapters:
0:00 Intro
0:13 corner-shape
0:48 shape function
1:44 Custom Selects
2:24 scroll-marker
3:12 scroll-state
4:26 stretch
5:05 text-box
6:31 sibling-index
7:10 if function
7:58 Custom Functions

• css