Introduction to css

Introduction to css

• 1.
  Cascading Style Sheet www.eshikshak.co.in
• 2.
  Introduction to CSS •CSS stands Cascading Style Sheets CSS • It handles the look and feel part of a web page, like – you can control the color of the text – the style of fonts – the spacing between paragraphs – what background images or colors are used, as well as a variety of other effects. • CSS is easy to learn and understand but it provides powerful control over the presentation of an HTML document. Most commonly, CSS is combined with the markup languages HTML or XHTML. www.eshikshak.co.in
• 3.
  Advantages of CSS • CSS saves time - You can write CSS once and then reuse same sheet in multiple HTML pages. You can define a style for each HTML element and apply it to as many Web pages as you want. • Pages load faster - If you are using CSS, you do not need to write HTML tag attributes every time. Just write one CSS rule of a tag and apply to all the occurrences of that tag. So less code means faster download times. • Easy maintenance - To make a global change, simply change the style, and all elements in all the web pages will be updated automatically. • Superior styles to HTML - CSS has a much wider array of attributes than HTML so you can give far better look to your HTML page in comparison of HTML attributes. • Multiple Device Compatibility - Style sheets allow content to be optimized for more than one type of device. By using the same HTML document, different versions of a website can be presented for handheld devices such as PDAs and cell phones or for printing. • Global web standards - Now HTML attributes are being deprecated and it is being recommended to use CSS. So its a good idea to start using CSS in all the HTML pages to make them compatible to future browsers. www.eshikshak.co.in
• 4.
  Who Creates andMaintains CSS? • CSS is created and maintained through a group of people within the W3C called the CSS Working Group. • The CSS Working Group creates documents called specifications. • When a specification has been discussed and officially ratified by W3C members, it becomes a recommendation. • NOTE: The World Wide Web Consortium, or W3C is a group that makes recommendations about how the Internet works and how it should evolve. www.eshikshak.co.in
• 5.
  Syntax • A CSScomprises of style rules that are interpreted by the browser and then applied to the corresponding elements in your document. A style rule is made of three parts: – Selector: A selector is an HTML tag at which style will be applied. This could be any tag like <h1> or <table> etc. – Property: A property is a type of attribute of HTML tag. Put simply, all the HTML attributes are converted into CSS properties. They could be color or border etc. – Value: Values are assigned to properties. For example color property can have value either red or #F1F1F1 etc. www.eshikshak.co.in
• 6.
  Syntax • You canput CSS Style Rule Syntax as follows selector table { { property: value; border :1px solid } #C00; } www.eshikshak.co.in
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  The Type Selectors h1 { color: #36CFFF; } to give a color to all level 1 headings : www.eshikshak.co.in
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  The Descendant Selectors ul em { color: #000000; } style rule will apply to <em> element only when it lies inside <ul> tag. www.eshikshak.co.in
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  The Class Selectors •Define style rules based on the class attribute of the elements. • All the elements having that class will be formatted according to the defined rule. <p class="center bold"> .black { This para will be styled by the classes color: #000000; center and bold. } </p> www.eshikshak.co.in
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  The ID Selectors •Define style rules based on the id attribute of the elements. • All the elements having that id will be formatted according to the defined rule. #black { color: #000000; } www.eshikshak.co.in
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  The ID Selectors •This rule renders the content in black for every element with id attribute set to black in our document. You can make it a bit more particular. For example: h1#black { color: #000000; } www.eshikshak.co.in
• 12.
  The Attribute Selectors •Apply styles to HTML elements with particular attributes. • The style rule below will match all input elements that has a type attribute with a value of text. • The advantage to this method is that the <input type="submit" /> element is unaffected, and the color applied only to the desired text fields. input[type="text"] { color: #000000; } www.eshikshak.co.in
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  • There arefollowing rules applied to attribute selector. – p[lang] - Selects all paragraph elements with a lang attribute. – p[lang="fr"] - Selects all paragraph elements whose lang attribute has a value of exactly "fr". – p[lang~="fr"] - Selects all paragraph elements whose lang attribute contains the word "fr". – p[lang|="en"] - Selects all paragraph elements whose lang attribute contains values that are exactly "en", or begin with "en-". www.eshikshak.co.in
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  Multiple Style Rules •You may need to define multiple style rules for a single element. You can define these rules to combine multiple properties and corresponding values into a single block as defined in the following example h1 { color: #36C; font-weight: normal; letter-spacing: .4em; margin-bottom: 1em; text-transform: lowercase; } www.eshikshak.co.in