• 🆕 CSS: attr() attribute text

• 🆕 CSS: color wheel spinner animation
• 🆕 CSS: Angle Units
• 🆕 CSS: Repeating Linear Gradient
• 🆕 CSS: Conic Gradient
• 🆕 CSS: Repeating Conic Gradient

• added pi and other math constants
• CSS: calc

• added name transparent
• CSS: Color Names

• explained about flex, anonymous item
• CSS: Centering

• CSS: readable text shadow for changing background color

• 🆕 CSS: Outline Text
• CSS: Text Shadow

updated

• CSS: Box Sizing

• CSS: inline-block not aligned, need vertical-align: top

• Wide Gamut Colors

• JS coding style example. codepoint to utf16 encoding (2026)

• 🆕 Serif vs Sans Serif Font (2026)

• 🆕 CSS: Core Web Fonts
• CSS: common web fonts

• WHATWG vs W3C Split. 2012

old article. interesting, found an article i wrote about this issue, back in 2011.

• HTML code tag inside pre (2011)

• CSS: cascade @layer

updates

• CSS: adjacent sibling selector (+)
• CSS: subsequent sibling selector (~)
• CSS: sibling rank selector (first, last, nth)
• CSS: child selector (>)

Major discovery. HTML is tag and attribute names are not case sensitive, but only for English letters.

• HTML: Case Sensitivity

major updates and new pages

• 🆕 CSS: cascade (rule priority, !important)
• 🆕 CSS: specificity

• CSS: selector types (simple, compound, complex (combinator), etc)
• 🆕 CSS: complex selector
• CSS: negation selector (:not)
• CSS: “is any of” selector (:is, :where)
• CSS: selector list (grouping selectors)

updated.

• CSS: Responsive Table
• CSS: font-weight, bold

• CSS: font shorthand

• JS DOM: Add style to HTML page

minor update

• JS DOM: Browser Window Object

• JS DOM: setTimeout, setInterval

major updates.

• CSS: nth-child selector
• CSS: sibling rank selector (first, last, nth)
• CSS: Styling HTML Table

• iPhone-style Chat Bubbles (ai answer. 2026-05-16)

lots updates

• CSS: descendant selector (space)
• CSS: adjacent sibling selector (+)
• CSS: child selector (>)
• CSS: subsequent sibling selector (~)

• programing language theory.
• Why is CSS selector syntax cannot use parenthesis for operator precedence
• great ai answer.
• without ai, questions like this take days to research.
• basically, it says it's designed that way, to be just linear syntax, so that it's easy parsing.
• anyhow, i think this is a design mistake.

• Why is CSS selector syntax cannot use parenthesis for operator precedence (2026)

• CSS Complexity PhD. (2026)

• CSS: ::marker (for list item)

• CSS: color scheme

• CSS: touch-action (phone screen)

minor updates.

• CSS: no child selector

• CSS: :has descendant selector

• JS: String.prototype.codePointAt (Char → ID)

added ::marker

• CSS: pseudo-element selector (::)

CSS touch-action property

idiotic phone. webdev.

if u have a html button, but on phone touching it is delayed. repeated fast press results is zoom or movement.

so, u need to set touch-action: manipulation; because otherwise, phone touch may scroll or double tab zoom.

• CSS: Linear Gradient
• CSS: Radial Gradient

massive updates.

• CSS: Colors. Index
• CSS Color Names
• CSS: RGB Color
• CSS: HSL Color
• CSS: Opacity (Transparency)

• CSS: Layout. Index

• CSS: attribute selector

• CSS: Syntax

• CSS: Text Shadow

• CSS: Box Sizing
• CSS: Margin vs Padding

• CSS rebecca purple, new color name 2025

• 🆕 CSS: Misc. Index

• 🆕 CSS: global keywords

• 🆕 CSS: nesting selector (ampersand &)

• CSS. Selector. Index
• 🆕 CSS: simple selectors
• 🆕 CSS: compound selectors

• CSS: complex selector (combinators)

advanced CSS and syntax issue in computer languages.

the relation of CSS Selector List, and the so-called pseudo selectors :is(), is a syntactic one, and critical one.

because :is() is a single syntactic unit, thus allows it to be grouped as part of other expression. but the selector list (of the comma operator), cannot.

• CSS: selector list (grouping selectors)

splitted out as new page.

• 🆕 CSS: subsequent sibling selector ~
• 🆕 CSS: adjacent sibling selector +

new pages

• 🆕 CSS: has descendant selector
• 🆕 CSS: is any of (is, where) selector
• 🆕 CSS: selector types: simple, compound, combinator, complex
• 🆕 CSS: pseudo-class function selector

updates:

• CSS: selector tutorial

• CSS: type selector (tag name)
• 🆕 CSS: class selector
• 🆕 CSS: ID selector
• CSS: attribute selector
• 🆕 CSS: selector list (grouping selectors)
• 🆕 CSS: universal selector (any tag)

updated.

• CSS: Insert Content Before or After Element
• CSS: Margin vs Padding
• CSS: List Bullet Style

• JS: thisBinding in setTimeout and setInterval

I watched the birth of CSS, becoming accepted around 2001. Now, after flexbox was added some 5 or 10 years ago, finally i wrote a tutorial on it.

• 🆕 CSS: Flexbox Layout

updates

• CSS: Font. Index

• CSS: Reset, Default Values

• Font Size Survey 2023

• CSS: OverFlow, Scrollbar

• JS: ECMAScript 2015
• JS: Difference of Object vs Map
• JS: Enumerable Property

• CSS: Text Decoration, Underline, Overline, Line Through, Wavy

• CSS: Box Sizing

• CSS: Length Units
• HTML: the Root Element
• CSS Selector: root element
• CSS: Variable (Custom Property)

• CSS: Selectors. Index

• JS DOM: decodeURI

• JS DOM: Insert, Remove, Replace Element

• incredible ai.
• took me days to research this ten years ago.
• now with ai, superb summary in few seconds.

• explain chinese font styles
• https://x.com/i/grok/share/760572296c2543678b037acd135b4231

• CSS: Chinese Font Guide 黑體 宋體
• Chinese Fonts on Mac
• Chinese Fonts on Windows

• Chinese character/font styles 汉字字体风格

• JS: Value Types
• JS: Primitive Value

• CSS: Pseudo Element
• CSS: Pseudo-Element Selectors
• CSS: Pseudo Class
• CSS: Pseudo-Class Selectors
• CSS: Selector Tutorial

• CSS: Insert Content Before or After Element

• JavaScript in Depth. by James M Snell (2026)

• JS DOM: Class Attribute (get add remove toggle)

• HTML: Audio Tag

• 🆕 JS DOM: decodeURI
• 🆕 JS DOM: decodeURIComponent

• Emoji Font from Google, Apple, Microsoft

• HTML: List: ul ol li
• HTML: Nested List
• CSS: List Style
• CSS: Flowing List
• HTML: Definition List: dl dt dd

• HTML: Video Tag

• Atom Webfeed (RSS) Tutorial