Go through what you see with your fingers to eliminate your impatience and deepen your impression. I admire the saying "do not read without writing"; after all, it is not the best to just look and understand. In order to avoid the embarrassing situation of being able to understand but not being able to read it, I started writing -
I was surprised and happy to see the word CSS framework.
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RGB
RGB color value is 16 The six-digit character of the hexadecimal # prefix can be abbreviated when there are pairs of repeated values. For example, #FFCCDD can be abbreviated to #FCD.
Group Definer
This is the name I gave you :), which is to define the styles of several tags at once, using ',' separated; such as p,li,div,a{font-size=12px;font-style:italic;font-weight:normal;}.
Derived definer
In fact, it is not accurate to say that it is derived. It is to define the style for the sub-elements inside an element. This sub-element can It is a type of tag (such as p) or it can have a specific id value; such as li strong{font-style:italic;font-weight:normal;} or li #li1{font-size:12px;}. The following is what I introduced myself. I don’t know if it can be used.
Identification Definer
It seems that the navy is the person who wrote div css books. I have not read his book. He calls this an ID selector, that is Write a style with special care for an element with an id attribute defined. For example, if there is a
on the page, the style defining it is #div1{text-align:right;margin-top: 10pt;background:#CCC;color:#000;}, there can also be derived definers. The identifier definer cannot begin with a number and cannot contain spaces or hyphens.
Define the pseudo-class of the link
4 pseudo-classes are used in css to define the style of the link, probably because the link has several states The reason is that I think other tags with multiple states should have similar behavior. a:link;a:active;a:hover;a:visited; is similar to the inheritance symbol ":" in programming languages. Define a:link{text-decoration:none/underline/;font-weight:bold;}.
Structured css code
I understand that structuring is to apply the several methods of defining styles introduced above to all elements on the page as much as possible Simple logical definition, at least not repetitive.
DT and DTD
DT is the abbreviation of DocumentType, the style mentioned above; DTD is the standard for the definition of document type; DT is the standard It is an indispensable key component of the page. Unless you declare the correct DT, your markup and CSS will not take effect; I don't know if this sentence is correct. The declaration format is as follows:
; There are three types of DTD: Traditional, Strict, and FrameSet. You can understand the general meaning from the words. We generally use Traditional. If all browsers in the future comply with W3C, this problem will not exist. La. Control structure (Table), presentation form (Style), and content (Content) are finer layers.
XHTML, XML
Values, whether to care about case, the different meanings of "--", some of the differences between XHTML and HTML.
CSS box model
Also note the black hat technology
Going to get off work Come home and make a quick note. The black hat technique is actually to define the height and width of the container as the minimum value to hide the elements inside. Such as p{line-width:0%;line-height:0%;}
Standard Verification
If you want to know whether the CSS you wrote meets the standards, you can go to See www.validator.w3.org.
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