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CSS3

Information Technology > Web page creation and editing

Description

CSS3, or Cascading Style Sheets level 3, is a language used in web development to style and layout web pages. It allows developers to control elements like color, font, and positioning, making websites visually appealing. CSS3 introduces new features like animations, gradients, and advanced selectors that offer more control over the design. It also includes flexbox and grid systems for more complex layouts. With media queries, CSS3 enables responsive design, allowing websites to adapt to different screen sizes. Mastery of CSS3 involves understanding performance optimization, scalable architecture, and using preprocessors like Sass for more efficient coding.

Expected Behaviors

LEVEL 1

Fundamental Awareness

At this level, individuals have a basic understanding of CSS3. They can write simple stylesheets using correct syntax and selectors, apply color codes, understand the box model, and manipulate text properties. However, their knowledge is mostly theoretical and they may need guidance to apply it in practice.

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LEVEL 2

Novice

Novices can independently write CSS3 code for simple web pages. They know how to use classes and IDs, understand basic layout properties like display and position, and can apply pseudo-classes and pseudo-elements. They also have a basic understanding of transitions and animations.

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LEVEL 3

Intermediate

Intermediate users are comfortable with CSS3 and can create responsive designs using media queries. They can use advanced selectors, understand flexbox layout, and create complex animations and transitions. They also know how to apply gradient backgrounds.

LEVEL 4

Advanced

Advanced users have a deep understanding of CSS3. They can use grid layouts, variables, and calculations, understand transform properties, and can apply custom fonts using @font-face. They also have a good grasp of advanced pseudo-classes and pseudo-elements.

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LEVEL 5

Expert

Experts have mastered CSS3 and can optimize performance, write maintainable and scalable CSS, and understand CSS preprocessors like Sass and Less. They are familiar with CSS architecture methodologies like BEM and SMACSS, and can use CSS in JS libraries like Styled Components and Emotion.

Micro Skills

LEVEL 1

Fundamental Awareness

Understanding the concept of CSS3
Knowledge of basic CSS syntax
Ability to use tag, class, and id selectors
Understanding of the difference between inline, internal, and external CSS
Understanding of RGB color codes
Familiarity with hexadecimal color codes
Knowledge of named colors in CSS
Understanding of padding, border, and margin
Knowledge of the content area
Awareness of the box-sizing property
Ability to change font size and color
Understanding of text alignment
Knowledge of line height and letter spacing properties
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LEVEL 2

Novice

Understanding the difference between classes and IDs
Knowing when to use a class versus an ID
Applying styles to elements using classes and IDs
Understanding the different display values (block, inline, inline-block)
Knowing how to use the position property (static, relative, absolute, fixed)
Applying these properties to control the layout of elements on a page
Knowing the difference between pseudo-classes and pseudo-elements
Using common pseudo-classes like :hover, :active, :first-child
Using common pseudo-elements like ::before, ::after
Understanding the syntax for creating CSS transitions
Creating simple animations using keyframes
Applying transitions and animations to HTML elements
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LEVEL 3

Intermediate

Knowledge of vw, vh, vmin, vmax units
Understanding of min-width and max-width in media queries
Understanding of device type media features
Knowledge of orientation media feature
Knowledge of attribute presence and value selectors
Understanding of child combinator and adjacent sibling combinator
Understanding of :not, :nth-child, and :nth-of-type pseudo-classes
Understanding of flex-direction, justify-content, align-items, and flex-wrap
Knowledge of flex-grow, flex-shrink, and flex-basis
Understanding of nested flex containers
Knowledge of align-self and justify-self
Knowledge of @keyframes rule and animation-name property
Understanding of animation-duration, animation-timing-function, and animation-delay
Understanding of animating multiple properties
Knowledge of linear, ease, ease-in, ease-out, and ease-in-out timing functions
Knowledge of linear-gradient function
Understanding of radial-gradient function
Understanding of repeating-linear-gradient and repeating-radial-gradient functions
Knowledge of color-stop syntax
LEVEL 4

Advanced

Knowledge of grid-template-columns and grid-template-rows
Understanding of grid-column and grid-row properties
Knowledge of justify-items and align-items
Knowledge of --* syntax for declaring variables
Understanding of var() function for using variables
Understanding of translate() function
Understanding of rotate() function
Knowledge of scale() function
Knowledge of font-family descriptor
Understanding of src descriptor
Knowledge of format descriptor
Knowledge of nth-child() pseudo-class
Understanding of nth-of-type() pseudo-class
Knowledge of first-child and last-child pseudo-classes
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LEVEL 5

Expert

Understanding of critical rendering path
Knowledge of CSS minification techniques
Ability to use CSS sprites
Proficiency in eliminating unnecessary CSS
Understanding of modular CSS
Ability to use CSS linting tools
Knowledge of CSS commenting best practices
Proficiency in organizing CSS files
Ability to use variables in Sass/Less
Understanding of mixins in Sass/Less
Knowledge of nesting rules in Sass/Less
Proficiency in using functions in Sass/Less
Understanding of Block Element Modifier (BEM) methodology
Knowledge of Scalable and Modular Architecture for CSS (SMACSS) principles
Ability to implement BEM/SMACSS in projects
Understanding of the benefits and drawbacks of BEM/SMACSS
Understanding of the concept of CSS-in-JS
Knowledge of Styled Components library
Proficiency in using Emotion library
Ability to create dynamic styles with CSS-in-JS
CSS3 Miscellaneous

Skill Overview

  • Expert2 years experience
  • Micro-skills79
  • Roles requiring skill14

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