CSS Combinators

A CSS selector can contain more than one simple selector. Between the simple selectors, we can include a combinator.

There are four different combinators in CSS:

  • Descendant combinator (space)
  • Child combinator (>)
  • Next sibling combinator (+)
  • Subsequent-sibling combinator (~)

Descendant Combinator

The descendant combinator matches all elements that are descendants of a specified element.

The following example selects all <p> elements inside <div> elements:

Example

div p {
background-color: yellow;
}

Continue reading CSS Combinators

CSS Layout – Align

Center Align Elements

To horizontally center a block element (like <div>), use margin: auto;

Setting the width of the element will prevent it from stretching out to the edges of its container.

The element will then take up the specified width, and the remaining space will be split equally between the two margins. Continue reading CSS Layout – Align

CSS Layout – display: inline-block

The display: inline-block Value

Compared to display: inline, the major difference is that display: inline-block allows to set a width and height on the element.

Also, with
display: inline-block, the top and bottom margins/paddings are respected, but with display: inline they are not.

Compared to display: block, the major difference is that display: inline-block does not add a line-break after the element, so the element can sit next to other elements.

The following example shows the different behavior of display: inline, display: inline-block and display: block:

Example

span.a {
display: inline; /* the default for span */
width: 100px;
height: 100px;
padding: 5px;
border: 1px solid blue;
background-color: yellow;
}

span.b {
display: inline-block;
width: 100px;
height: 100px;
padding: 5px;
border: 1px solid blue;
background-color: yellow;
}

span.c {
display: block;
width: 100px;
height: 100px;
padding: 5px;
border: 1px solid blue;
background-color: yellow;
}

Continue reading CSS Layout – display: inline-block

CSS Layout – float and clear

The CSS float property specifies how an element should float.

The CSS clear property specifies what elements can float beside the cleared element and on which side.

The float Property

The float property is used for positioning and formatting content e.g. let an image float left to the text in a container.

The float property can have one of the following values:

  • left – The element floats to the left of its container
  • right – The element floats to the right of its container
  • none – The element does not float (will be displayed just where it occurs in the text). This is default
  • inherit – The element inherits the float value of its parent

In its simplest use, the float property can be used to wrap text around images. Continue reading CSS Layout – float and clear

CSS Layout – Overflow

The CSS overflow property controls what happens to content that is too big to fit into an area.

CSS Overflow

The overflow property specifies whether to clip the content or to add scrollbars when the content of an element is too big to fit in the specified area.

The overflow property has the following values:

  • visible – Default. The overflow is not clipped. The content renders outside the element’s box
  • hidden – The overflow is clipped, and the rest of the content will be invisible
  • scroll – The overflow is clipped, and a scrollbar is added to see the rest of the content
  • auto – Similar to scroll, but it adds scrollbars only when necessary

Continue reading CSS Layout – Overflow

CSS Layout – z-index

The z-index property specifies the stack order of an element.

The z-index Property

When elements are positioned, they can overlap other elements.

The z-index property specifies the stack order of an element (which element should be placed in front of, or behind, the others).

An element can have a positive or negative stack order:

Continue reading CSS Layout – z-index

CSS Layout – Position

The position property specifies the type of positioning method used for an element (static, relative, fixed, absolute or sticky).

The position Property

The position property specifies the type of positioning method used for an element.

There are five different position values:

  • static
  • relative
  • fixed
  • absolute
  • sticky

Elements are then positioned using the top, bottom, left, and right properties. However, these properties will not work unless the position property is set first. They also work differently depending on the position value.

Continue reading CSS Layout – Position

CSS Layout – Width

Using width, max-width and margin: auto;

As mentioned in the previous chapter; a block-level element always takes up the full width available (stretches out to the left and right as far as it can).

Setting the width of a block-level element will prevent it from stretching out to the edges of its container. Then, you can set the margins to auto, to horizontally center the element within its container. The element will take up the specified width, and the remaining space will be split equally between the two margins:

This <div> element has a width of 500px, and margin set to auto.

 

Note: The problem with the <div> above occurs when the browser window is smaller than the width of the element. The browser then adds a horizontal scrollbar to the page. Continue reading CSS Layout – Width

CSS Layout – Display

The display property is the most important CSS property for controlling layout.

The display Property

The display property is used to specify how an element is shown on a web page.

Every HTML element has a default display value, depending on what type of element it is. The default display value for most elements is block or inline.

The display property is used to change the default display behavior of HTML elements.

Block-level Elements

A block-level element ALWAYS starts on a new line and takes up the full width available (stretches out to the left and right as far as it can).

The <div> element is a block-level element.

Examples of block-level elements:

  • <div>
  • <h1> – <h6>
  • <p>
  • <form>
  • <header>
  • <footer>
  • <section>

Inline Elements

An inline element DOES NOT start on a new line and only takes up as much width as necessary.

This is an inline <span> element inside a paragraph.

Examples of inline elements:

  • <span>
  • <a>
  • <img>

Continue reading CSS Layout – Display

CSS Tables

The look of an HTML table can be greatly improved with CSS:

Company Contact Country
Alfreds Futterkiste Maria Anders Germany
Berglunds snabbköp Christina Berglund Sweden
Centro comercial Moctezuma Francisco Chang Mexico
Ernst Handel Roland Mendel Austria
Island Trading Helen Bennett UK
Königlich Essen Philip Cramer Germany
Laughing Bacchus Winecellars Yoshi Tannamuri Canada
Magazzini Alimentari Riuniti Giovanni Rovelli Italy

Continue reading CSS Tables