Cascading Style Sheets (CSS)
Cascading Style Sheets (CSS) is a computer-language that describes how XML and HTML documents should be visually presented. One of the best ways to learn CSS is through the MDN CSS Learning Arena.
CSS Best Practices
- Use a CSS Reset or Normalizer: Establish consistent styles across browsers by using a CSS reset, such as normalize.css.
- Avoid inline CSS: Use external CSS files for better flexibility, reusability, and maintainability.
- Avoid overly specific selectors: Use classes and IDs instead of relying heavily on complex nested selectors.
- Optimize and minify: Optimize and minify CSS prior to deployment to reduce file size and improve loading performance.
- Keep it responsive: Use media queries to adjust styles based on different screen sizes and resolutions to ensure a functional user experience across devices.
Lesser known CSS selectors
Peer element selector
Use +
as the peer element selector to select an adjacent peer element. For example, to select a <span>
that immediately follows a <div>
, use this CSS:
div + span {
/* ... */
}
The code above will select the span in this HTML because the <span>
appears immediately after the <div>
:
<div>...</div>
<span>...</span>
Subsequent sibling selector
Use ~
as the subsequent sibling selector to select elements that appear after, not not necessarily adjacent to, another element. For example, to select a <span>
that follows a <div>
but has one or more elements in between the <div>
and the <span>
, use this CSS:
div ~ span {
/* ... */
}
The code above will select the span in this HTML:
<div>...</div>
<p>...</p>
<span>...</span>
CSS Resources
Deeper Knowledge on Cascading Style Sheets (CSS)
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Sassy Cascading Stylesheets (SCSS)
A superset of CSS that adds variables, mixins, functions, and more to CSS
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CSS recipes
Quick and easy to copy recipes for CSS
Broader Topics Related to Cascading Style Sheets (CSS)
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Web Development
Tools and techniques for building websites and web-applications
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Computer Languages
Computer Languages: How humans tell computers what to do