CSS logical properties control borders, size, margin, and padding with directions and dimensions relative to the writing mode. For example, in a left to right, top to bottom writing mode, block-end refers to the bottom. Also known as flow relative.

The aspect-ratio CSS property controls the width-to-height ratio of elements. For <img> and <video> elements, the width and height attributes used together with height: auto control the aspect ratio while the image/video is loading.

The quotes CSS property sets the quotation marks inserted via the content CSS property or <q> element.

The min() and max() CSS functions return the minimum or maximum of the arguments, while clamp() clamps a value to a given range.

The overflow CSS property sets the behavior for when content doesn't fit in an element.

The CSS.supports() static method returns whether the browser supports a CSS declaration (given by two arguments, a property and value) or an @supports at-rule condition string.

The unicode-bidi and direction CSS properties override the Unicode layout algorithm. They are intended for Document Type Definition (DTD) designers. For HTML documents, you should use the dir global HTML attribute and <bdo> HTML element instead.

The caret-color CSS property sets the color of the text insertion pointer in a text input.

The display: flow-root CSS declaration sets an element as the root element of a new flow layout for its children, preventing margin collapse with sibling elements.

The will-change CSS property gives hints to the browser about expected changes to an element's scroll position, contents, or style. These hints allow browsers to optimize for upcoming style changes.

Custom properties are CSS properties prefixed with -- that set values you can reuse with the var() function. For example, you can set a --key-color property to reuse as border-color: var(--key-color). Also known as CSS variables.

The -webkit-text-stroke-width and -webkit-text-stroke-color CSS properties set the thickness and color of text outlines. The -webkit-text-fill-color sets the color within text character outlines. Both default to the text color.

The writing-mode CSS property sets whether text is laid out horizontally or vertically, and left to right, or right to left.

The filter CSS property applies one or more graphic effects to an element. You can use filter functions, such as blur() and drop-shadow(), alone or combined to produce different effects. For instance, filter: blur(2px).

The @supports at-rule applies styles based on a browser's support for CSS features, such as a CSS property and value. Also known as feature queries.

The animation CSS property animates an element's style over time, using keyframes described in @keyframes rules.

The @charset CSS at-rule specifies the character encoding of an external style sheet.

The @import CSS at-rule loads styles from another stylesheet.

The @namespace CSS rule sets a default namespace or namespace prefix. Namespace prefixes allow CSS selectors to distinguish elements with the same name but different document types, such as the HTML <a> element and the SVG <a> element.

The color CSS property sets the primary foreground color of an element, which is used for text, the default border color, and text decorations.

The content CSS property sets the content inside of an element or pseudo-element, replacing the current value. It's often used with the ::before and ::after pseudo-elements to generate cosmetic content.

The display CSS property sets the display behavior of an element's box within its layout and sets the layout behavior for its child elements.

The physical CSS properties, top, right, bottom, and left, set the inset position of an element relative to the corresponding side of a container determined by the element's position property.

The text-overflow CSS property sets how hidden overflow content appears to users. The property can clip content, truncate content with an ellipsis (…), or truncate with a custom string.

The attr() CSS function, in content property declarations, sets a ::before or ::after pseudo-element's content to the value of the specified HTML attribute.

The calc() CSS function computes mathematical expressions such a calc(100%/3 - 1em).

The display: list-item CSS declaration renders an element with the box layout of a <li> HTML element.

The display: table CSS declaration renders an element with the box layout of a <table> HTML element. Child elements may use equivalents to <table> internal elements such as display: table-row for <tr>.

The float CSS property aligns an element to either side of its container, allowing text and inline elements to flow around it. The clear CSS property sets whether an element is moved below floating elements that proceed it.

The opacity CSS property sets the transparency of an element.