教程css英文語法
Syntax
The CSS syntax is made up of three parts: a selector, a property and a value:
selector {property:value}
The selector is normally the HTML element/tag you wish to define, the property is the attribute you wish to change, and each property can take a value. The property and value are separated by a colon, and surrounded by curly braces:
body {color:black}
Note: If the value is multiple words, put quotes around the value:
p {font-family:"sans serif"}
Note: If you want to specify more than one property, you must separate each property with a semicolon. The example below shows how to define a center aligned paragraph, with a red text color:
p {text-align:center;color:red}
To make the style definitions more readable, you can describe one property on each line, like this:
p
{
text-align:center;
color:black;
font-family:arial
}
Grouping
You can group selectors. Separate each selector with a comma. In the example below we have grouped all the header elements. All header elements will be displayed in green text color:
h1,h2,h3,h4,h5,h6
{
color:green
}
The class Selector
With the class selector you can define different styles for the same type of HTML element.
Say that you would like to have two types of paragraphs in your document: one right-aligned paragraph, and one center-aligned paragraph. Here is how you can do it with styles:
t {text-align:right}
er {text-align:center}
You have to use the class attribute in your HTML document:
This paragraph will be right-aligned.
This paragraph will be center-aligned.
Note: To apply more than one class per given element, the syntax is:
This is a paragraph.
The paragraph above will be styled by the class "center" AND the class "bold".
You can also omit the tag name in the selector to define a style that will be used by all HTML elements that have a certain class. In the example below, all HTML elements with class="center" will be center-aligned:
er {text-align:center}
In the code below both the h1 element and the p element have class="center". This means that both elements will follow the rules in the "er" selector:
This heading will be center-aligned
This paragraph will also be center-aligned.
Do NOT start a class name with a number! This is only supported in Internet Explorer.
Add Styles to Elements with Particular Attributes
You can also apply styles to HTML elements with particular attributes.
The style rule below will match all input elements that have a type attribute with a value of "text":
input[type="text"] {background-color:blue}
The id Selector
You can also define styles for HTML elements with the id selector. The id selector is defined as a #.
The style rule below will match the element that has an id attribute with a value of "green":
#green {color:green}
The style rule below will match the p element that has an id with a value of "para1":
p#para1
{
text-align:center;
color:red
}
Do NOT start an ID name with a number! It will not work in Mozilla/Firefox.
CSS Comments
Comments are used to explain your code, and may help you when you edit the source code at a later date. A comment will be ignored by browsers. A CSS comment begins with "/*", and ends with "*/", like this:
/*This is a comment*/
p
{
text-align:center;
/*This is another comment*/
color:black;
font-family:arial
}
-
如何理解Javascript的caller,callee,call,apply區別
在提到上述的概念之前,首先想說說javascript中函式的隱含引數:argumentsarguments該物件代表正在執行的函式和呼叫它的函式的引數。[function.]arguments[n]引數function:選項。當前正在執行的Function物件的名字。n:選項。要傳遞給Function物件的從0開始的引數值...
-
PHP開發工程師的主要職責
PHP開發工程師的主要職責1職責:1、負責公司後端的研發,保障系統的穩定性和質量2、與業務需求部門及專案經理溝通,理解需求,進行架構設計;3、搭建開發框架、負責核心程式碼的編寫,解決技術難點;4、界定、分析和解決系統中存在的問題和缺陷;5、對系統進行持續改進,提升系...
-
如何理解Javascript的caller,callee,call,apply區別
在提到上述的概念之前,首先想說說javascript中函式的隱含引數:argumentsarguments該物件代表正在執行的函式和呼叫它的函式的引數。[function.]arguments[n]引數function:選項。當前正在執行的Function物件的名字。n:選項。要傳遞給Function物件的從0開始的引數值...
-
css經典教程
css經典教程1有些習慣顯得尤為重要,今天與您分享六個CSS習慣。因為習慣其實是會變的,所以只能寫“最近”的。這些習慣都跟技術無關,如果不遵守,也不會出錯。但是我覺得良好的習慣會體現一個人的素質。我們在中向大家介紹過很多CSS經驗與技巧,這些東西都發布在/css/...