CSS Interview Questions

The full form of CSS is Cascading Style Sheets. It is a styling language which is simple enough for HTML elements. It is popular in web designing, and its application is common in XHTML also.

Standard Generalized Markup Language marked the beginning of style sheets in 1980s.

The variations for CSS are:

Primis Player Placeholder

CSS 1
CSS 2
CSS 2.1
CSS 3
CSS 4

Limitations are:

Ascending by selectors is not possible Limitations of vertical control No expressions No column declaration Pseudo-class not controlled by dynamic behavior Rules, styles, targeting specific text not possible

Advantages are:

Bandwidth
Site-wide consistency
Page reformatting
Accessibility
Content separated from presentation

It is a pre-planned libraries, which allows easier and more standards-compliant webpage styling, using CSS language.

World Wide Web Consortium maintains the CSS specifications.

CSS can be integrated in three ways:

Inline: Style attribute can be used to have CSS applied HTML elements.
Embedded: The Head element can have a Style element within which the code can be placed.
Linked/ Imported: CSS can be placed in an external file and linked via link element.

Benefits:

One file can be used to control multiple documents having different styles. Multiple HTML elements can have many documents, which can have classes. To group styles in composite situations, methods as selector and grouping are used.

Merits of Embedded Style Sheets:

Multiple tag types can be created in a single document. Styles, in complex situations, can be applied by using Selector and Grouping methods. Extra download is unnecessary.

Demerits of Embedded Style Sheets:

Multiple documents cannot be controlled

A string equivalent of HTML elements by which declarations or a set of it, is declared and is a link that can be referred for linking HTML and Style sheet is CSS selector.

The design and customization of documents are rendered by media. By applying media control over the external style sheets, they can be retrieved and used by loading it from the network.

While physical tags are also referred to as presentational mark-up, logical tags are useless for appearances. Physical tags are newer versions while logical tags are old and concentrate on content.

While HTML provides easy structure method, it lacks styling, unlike Style sheets. Moreover, style sheets have better browser capabilities and formatting options.

W3C stands for World Wide Web Consortium. Its purpose is to deliver the information of the World Wide Web. It also develops rules and guidelines for the Web.

Although, there are no case-sensitivity of CSS, nevertheless font families, URL’s of images, etc is. Only when XML declarations along with XHTML DOCTYPE are being used on the page, CSS is case -sensitive.

A catalog of directions within braces consisting of property, colon and value is called declaration block.

They are:

Font-style Font-variant Font-weight Font-size/line-height Font-family Caption Icon

Importing enables combining external sheets to be inserted in many sheets. Different files and sheets can be used to have different functions. Syntax:

@import notation, used with <Style> tag.

Selectors that are unique to a specific style, are called CLASS selectors. Declaration of style and association with HTML can be made through this. Syntax:

Classname it can be A-Z, a-z or digits. .top {font: 14em ;}, class selector this class is associated with element

While an overall block is given to class selector, ID selector prefers only a single element differing from other elements. In other words, ID are uniques while classes are not. Its possible that an element has both class and ID.

Yes, it can be achieved by using a semicolon.

Pseudo-elements are used to add special effects to some selectors. CSS in used to apply styles in HTML mark-up. In some cases when extra mark-up or styling is not possible for the document, then there is a feature available in CSS known as pseudo-elements. It will allow extra mark-up to the document without disturbing the actual document.

While making the float declaration, 1 pixel is added every time it is used in the form of the border, and even more float is allowed thereafter.

In CSS, you cannot revert back to old values due to lack of default values. The property can be re- declared to get the default property.

Different media has different properties as they are case insensitive.

They are:

Aural – for sound synthesizers and speech Print – gives a preview of the content when printed Projection- projects the CSS on projectors. Handheld- uses handheld devices. Screen- computers and laptop screens.

This box defines design and layout of elements of CSS. The elements are:

Margin: the top most layer, the overall structure is shown Border: the padding and content option with a border around it is shown. Background color affects the border. Padding: Space is shown. Background colour affects the border. Content: Actual content is shown.

Selector used to select special occurrences of an element is called contextual selector. A space separates the individual selectors. Only the last element of the pattern is addressed in this kind of selector

A color can be specified in two ways:

A color is represented by 6 characters i.e. hexadecimal color coding. It is a combination of numbers and letters and is preceded by #. e.g.: g {color: #00cjfi} A color is represented by a mixture of red, green and blue. The value of a color can also be specified. e.g.: rgb(r,g,b): In this type the values can be in between the integers 0 and 255. rgb(r%,g%,b%): red, green and blue percentage is shown.

Dimension properties can be defined by:

Height
Max-height
Max-width
Min-height
Min-width
Width

By float property, the image can be moved to the right or the left along with the text to be wrapped around it. Elements before this property is applied do not change their properties.

Overlapping may occur while using CSS for positioning HTML elements. Z index helps in specifying the overlapping element. It is a number which can be positive or negative, the default value being zero.

In case the component fails, it will continue to work properly in the presence of a graceful degradation. The latest browser application is used when a webpage is designed. As it is not available to everyone, there is a basic functionality, which enables its use to a wider audience. In case the image is unavailable for viewing, text is shown with the alt tag.

It’s an alternative to graceful degradation, which concentrates on the matter of the web. The functionality is same, but it provides an extra edge to users having the latest bandwidth. It has been into prominent use recently with mobile internet connections expanding their base.

HTML sheet methods is collaborated with CSS and used accordingly.

@import is preferred only at the top, to avoid any overriding rules. Generally, ranking order is followed in most programming languages such as Java, Modula, etc. In C, the # is a prominent example of a @import being at the top.

CSS is more precedent over HTML procedures. Browsers, which do not have CSS support, display HTML attributes.

The Inline style in a CSS is used to add up styling to individual HTML elements.

The comments in CSS can be added with /* and */.

It is defined by a set of elements, value and its parts

A style, that helps in influencing CSS. E.g. FONT. They have corresponding values or properties within them, like FONT has different style like bold, italic etc.

Alternate Style Sheets allows the user to select the style in which the page is displayed using the view>page style menu. Through Alternate Style Sheet, user can see a multiple version of the page on their needs and preferences.

Quotes are optional in URL’s, and it can be single or double.

Rule, which is applicable in the entire sheet and not partly, is known as at-rule. It is preceded by @ followed by A-Z, a-z or 0-9.

In short, there is no easy way to restore to default values to whatever a browser uses.

The closest option is to use the 'initial' property value, which restores the default CSS values, rather than the browser's default styles.

The z-index helps to specify the stack order of positioned elements that may overlap one another. The z-index default value is zero and can take on either a positive or negative number.

An element with a higher z-index is always stacked above than a lower index.

Z-Index can take the following values:

Auto: Sets the stack order equal to its parents. Number: Orders the stack order. Initial: Sets this property to its default value (0). Inherit: Inherits this property from its parent element.

W3C stands for World Wide Web Consortium. Its purpose is to deliver the information of the World Wide Web. It also develops rules and guidelines for the Web.

It is the process of generating intermediate frames between two images.

It gives the impression that the first image has smoothly evolved into the second one.

It is an important method used in all types of animations. In CSS3, Transforms (matrix, translate, rotate, scale) module can be used to achieve tweening

RGB is a system of representing a certain colour in CSS. There are three streams in this nomenclature of representing a colour, namely the Red, Green and Blue stream. The intensity of the three colours is represented in numbers ranging from 0 to 256. This allows CSS to have a wide range of colours spreading across the entire spectrum of visible colours.

These conclude the easy section. Here is getting started documentation for CSS. Things are going to get a much more particular now. It’s time for intermediate CSS interview questions.

Some CSS Style components are:

Selector
Property
Value

The p[lang] command is used for selecting all the elements of a paragraph.

It is used for defining percentage values.

The background-position property is used to define the initial position of the background image. By default, the background image is placed on the top-left of the webpage.

You can set the following positions:

center
top
bottom
left
right

The ruleset is used to identify that selectors can be attached with other selectors. It has two parts:

Selector - Selector indicates the HTML element you want to style. Declaration Block - The declaration block can contain one or more declarations separated by a semicolon.

You can create classes for reusing it in many documents. By using it, you can control the styles of multiple documents from one file.
In complex situations, you can use selectors and grouping methods to apply styles.

RWD stands for Responsive Web Design. This technique is used to display the designed page perfectly on every screen size and device, for example, mobile, tablet, desktop and laptop. You don't need to create a different page for each device.

If a web page has a large number of images that take a longer time to load because each image separately sends out an HTTP request. The concept of CSS sprites is used to reduce the loading time for a web page because it combines the various small images into one image. It reduces the number of HTTP requests and hence the loading time.

Physical tags are referred to as presentational markup while logical tags are useless for appearances. Physical tags are newer versions, on the other hand, logical tags are old and concentrate on content.

In short, there is no easy way to restore to default values to whatever a browser uses.

The closest option is to use the 'initial' property value, which restores the default CSS values, rather than the browser's default styles.

The z-index helps to specify the stack order of positioned elements that may overlap one another. The z-index default value is zero and can take on either a positive or negative number.

An element with a higher z-index is always stacked above than a lower index.
Z-Index can take the following values:
Auto: Sets the stack order equal to its parents. Number: Orders the stack order. Initial: Sets this property to its default value (0). Inherit: Inherits this property from its parent element.