Easy everything in CSS & Design Systems, page 4
The `gap` Property: Spacing Without Margin Hacks
The gap property adds space *between* elements in a layout, not around them. Use it on Flexbox, Grid, or multi-column containers for clean, consistent gutters.
CSS Grid: Defining a 2D Layout Container
Turn an element into graph paper with display: grid, making its children items you can place in rows and columns. It's ideal for page-level layouts or complex components. The footgun: grid properties only apply to direct children, not nested elements.
CSS Flexbox: Mastering the Main and Cross Axis
Flexbox treats layout as a one-dimensional problem: either a row or a column. All alignment rules operate along a 'main axis' and a perpendicular 'cross axis'. Use it for navbars or card components.
border-radius: More Than Just Rounded Corners
The border-radius property rounds an element's corners, used for everything from buttons to circular avatars. The footgun is its shorthand syntax: one value is simple, but two, three, or four values follow specific clockwise rules that are easy to mix up.
CSS `background`: The All-in-One Shorthand
The CSS background property is a shortcut for styling an element's backdrop, combining color, image, and position in one line. Use it for most background tasks, from simple colors to complex layered images.
CSS `font`: The All-in-One Typography Shorthand
The font property is a single CSS declaration for setting multiple type styles at once, like size, weight, and family. Use it to define base typography for your site or components.
CSS Color Values: From Keywords to Functions
CSS offers multiple ways to define colors, from simple names like red to functions like rgb(). Use keywords for mockups, hex for design handoffs, and HSL for intuitive manipulation. The main footgun: colors can look different across uncalibrated devices.
CSS Selectors: How to Target HTML for Styling
CSS selectors are like addresses for your HTML, telling the browser which elements to style. They're used to apply everything from colors to layouts. The main footgun is specificity: an overly specific selector can be difficult to override later.
CSS Inheritance: Styles Flow Downhill
CSS inheritance is like genetics for web elements: children inherit styles like color and font-family from their parents. This is why setting a font on <body> styles a whole page.
CSS Box Model: Every Element is a Box
Every HTML element is a box with layers: content, padding, border, and margin. This model dictates how elements take up space and align, forming the basis of all CSS layout. The footgun is the default sizing, which adds padding *outside* the set width.
CSS Specificity: The Browser's Tie-Breaking Rule
CSS Specificity is the browser's tie-breaking system for conflicting styles. Think of it as a score: an ID is worth more than any number of classes, and a class is worth more than any number of elements. The footgun: using !important to win.
CSS Cascade: How Browsers Resolve Style Conflicts
The CSS Cascade is a tie-breaking algorithm that decides which style rule applies when multiple rules target the same element. It resolves conflicts between browser defaults, user styles, and your CSS.
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