The dominant-baseline attribute specifies the dominant baseline, which is the baseline used to align the box's text and inline-level contents. It also indicates the default alignment baseline of any boxes participating in baseline alignment in the box's alignment context.

The in operator returns true if the specified property is in the specified object or its prototype chain.

The elevation attribute specifies the direction angle for the light source from the XY plane towards the Z-axis, in degrees. Note that the positive Z-axis points towards the viewer of the content.

The bitwise AND assignment (&=) operator performs bitwise AND on the two operands and assigns the result to the left operand.

The font-variant attribute indicates whether the text is to be rendered using variations of the font's glyphs.

The logical AND assignment (&&=) operator only evaluates the right operand and assigns to the left if the left operand is truthy.

The export declaration is used to export values from a JavaScript module. Exported values can then be imported into other programs with the import declaration or dynamic import. The value of an imported binding is subject to change in the module that exports it — when a module updates the value of a binding that it exports, the update will be visible in its imported value.

The strict equality (===) operator checks whether its two operands are equal, returning a Boolean result. Unlike the equality operator, the strict equality operator always considers operands of different types to be different.

The logical OR (||) (logical disjunction) operator for a set of operands is true if and only if one or more of its operands is true. It is typically used with boolean (logical) values. When it is, it returns a Boolean value. However, the || operator actually returns the value of one of the specified operands, so if this operator is used with non-Boolean values, it will return a non-Boolean value.

The multiplication assignment (*=) operator performs multiplication on the two operands and assigns the result to the left operand.