Advanced HTML


Key points
  • HTML uses CSS to describe a document's appearance.
  • Using the style attribute, most tags allow you to change their appearance.
  • Styles cascade from a parent element to all of the other elements in it. Web browsers combine all of the styles to determine the final appearance of the element.

Previous sections introduced how to format text with bold and italics. What about color? HTML provides a wide range of options for changing the appearance of an HTML document. There are three ways to add styles to HTML, but all of them are very similar. This section will focus on one: the style attribute.


First, we need a way to describe how an HTML document should look. Recall from the HTML Introduction section that HTML defines the structure of a document. To tell web browsers about the appearance of a document, we use a form of Cascading Style Sheets (CSS). In general, HTML documents include style sheets written in CSS that the web browser combines with the HTML to add visual styles to the structure of the text. However, HTML also allows small pieces of CSS code to be embedded into each tag using the style attribute.

For example, this paragraph was centered using the style attribute.

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<p style="text-align: center;">For example, this paragraph was centered using the style attribute.</p>
Using the style attribute to center a paragraph

You can click here to view this page with the CSS styles removed.

The Style Attribute

The style attribute can appear on most HTML tags that contain content (such as <p>, <table>, <ul>, and even <i>). The value of the style attribute is a bit of CSS that controls the appearence of that HTML element (remember that HTML elements include the actual tag and its content). CSS styles are of the form "property: value;". Property determines what part of the element's apperance it being defined, and value is that definition. Here's another example of using styles:

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<table border="1" style="text-align: center;">
		<td style="color: red;">red</td>
		<td style="color: blue;">blue</td>
		<td style="color: green; width: 200px;">wide green</td>
Using different styles
red blue wide green

When applied to the table, the text-align style property affects all of the text in the table. Also, each table cell receives its own color style, which changes the text color. The last table cell defines two style properties, color and width, separated by a semicolon. The combination of multiple properties from different tags is called style cascading, which is the source of the name of CSS. A single HTML element's appearance is affected not only by its own style attribute, but the styles of each of its parent elements as well.

Common Style Properties

Later sections will go into more detail about styling text and using color, but here are some basic CSS properties that you can use in an element's style attribute:

Property Values Result
text-align left, center, right, or justify This text is right aligned
color a color name (like red or teal) Teal?
width, height number of pixels (px) or in em

Em units depend on the current font

background-color a color name (like blue or olive) Try applying this property to the <body> tag
border width type color Some common border types are solid, double, dashed, and groove
font-size xx-small, medium, xx-large, etc. or a number in px Font size can also be a percentage of the parent element's font
Click to view Live Example

<table border="1">
		<td>left, center, right, or justify</td>
		<td style="text-align: right;">This text is right aligned</td>
		<td>a color name (like red or teal)</td>
		<td style="color: teal;">Teal?</td>
		<td>width, height</td>
		<td>number of pixels (px) or in em</td>
		<td><p style="width: 10em;">Em units depend on the current font</p></td>
		<td>a color name (like blue or olive)</td>
		<td style="background-color: olive;">Try applying this property to the body tag</td>
		<td><i>width</i> <i>type</i> <i>color</i></td>
		<td style="border: 5px double maroon;">Some common border types are solid, double, dashed, and groove</td>
		<td>xx-small, medium, xx-large, etc. or a number in px</td>
		<td style="font-size: 200%;">Font size can also be a percentage of the parent element's font</td>
Some common CSS style properties