In the BEM (Block Element Modifier) methodology, elements are represented with a single hyphen - connecting the block and element names. Therefore, the correct way to represent an element named "item" inside a block named "menu" is by using the class .menu-item.

The primary benefit of using tools like PostCSS in modern web development workflows is that it allows you to write CSS in JavaScript files, which enhances code modularity. PostCSS enables the use of CSS features that might not be available in traditional CSS, making it a powerful tool for optimizing and streamlining your styles.

When working on a large-scale project, the BEM (Block Element Modifier) methodology is highly appropriate. BEM encourages the creation of modular and reusable CSS code by structuring classes in a way that makes it easy to understand their purpose. It follows a strict naming convention, which helps maintainability as the project grows.

To emphasize the first line of every paragraph differently from the rest of the content, you should use the ::first-line pseudo-element in CSS. This pseudo-element targets the first line of a block-level element and allows you to apply specific styling to it.

To hide an element but maintain its space in the layout, you would use 'display: none;'. This property effectively removes the element from the display, but it still occupies space, which can be useful for various purposes.

When you apply the CSS float property to an element, it is removed from the normal document flow. This means that other elements may flow around it as if it doesn't occupy space.

In SASS/SCSS, a mixin is defined using the @mixin directive followed by the mixin name and parentheses. The correct syntax is @mixin myMixin() { ... }. Mixins are used to encapsulate reusable sets of styles and can take parameters inside the parentheses if needed.

If a CSS rule has the !important declaration, it takes the highest precedence, regardless of the specificity of other rules. The !important rule will override any conflicting rule, even if it has a higher specificity.

The primary purpose of the letter-spacing property in CSS is to adjust the space between letters in text. It allows you to increase or decrease the space between characters, making text more tightly packed or more spaced out, which can be useful for achieving specific design or typographic effects.

The CSS property that controls whether an element is displayed on the page is the display property. It determines the rendering behavior of an element, and it can be set to values like none, block, inline, and more to control how the element is visually presented on the page. For example, setting display: none; will make the element invisible and take up no space on the page.

The grid-area property is used to span multiple rows and columns in a grid layout. By defining the starting and ending grid lines within this property, you can control how many rows and columns your grid item spans.

The 'padding' property in CSS affects the space inside an element. It determines the spacing between the element's content and its border, creating internal space.