HTML&CSS FAQ (v)

81. What are the common white hat optimization techniques for SEO in HTML? 82. What is the difference between a block attribute label and a row property label? Which tags are block properties and which are rows

See my blog: http://www.cnblogs.com/shireyhu/p/7814156.html

What's the difference between 83.ie6 and IE7? (obsolete, no reference value) 84. With three brothers Div, give Div design style float:left, how to make the second div not floating (cannot use CSS3 selector)

Add a float:none to the 2nd div;

85. Write out the CSS style of the two Div side, require the left div width 200px, font bold, line height 30px, margin 10px to right div, right div width adaptive, border 1px gray;

86.CSS style references and JS introduced position problems (why put on the head or the bottom)

In the development of web pages, as far as possible to put CSS in the page header, JS whether the external introduction or embedded JS fragment should be placed on the tail of the page

Because the page at the time of loading, CSS loading can be requested concurrently (the picture on the same page, except IE6), and JS loading needs to wait for a JS file loading completed before loading other resources, in order to quickly render the page, placed in the tail effect better

At the same time, because the embedded JS fragment will block the rendering of the entire page (the external introduction of JS file blocking other resource downloads, will also block the JS introduction location below the content rendering of the page, so to be placed at the bottom of the page)

87. The following are established (ABCD)

Labels that correctly mark the lines in 88.XHTML are
89. Browsers that do not support the Overflow-y property below are (IE7)

90. Read the following code, what is the vertical margin of the adjacent div?

The vertical margin of the adjacent Div is 50px

91. Read the following code, div#a and div#b which stack level is higher, a covers B or B covers a?

A cover B

92. What are the benefits of label semantics and CSS naming semantics?

* The page structure is still clear when you remove the style or the style is lost

* Mobile device can be more perfect to display your Web page (mobile device support for CSS is weaker)

* The reader will automatically parse according to the semantics of the tags, presenting a more readable form of content (accessible reading)

* Search engine determines context and weight issues based on the semantics of tags

* Convenient for later development and maintenance, more efficient team work

93. Some effect, there are two implementations can be achieved, scheme one, IMG tag, scenario Two: Background map, two options how to choose? What is the standard of measurement?

The following scenarios are appropriate for using IMG Tags:

* If the image is part of the content or chart or person, use the IMG tag plus alt attribute

* If you want to print the page and the image you want to include by default uses IMG

* Using an IMG (alt text) image has an important semantic, such as a warning icon, which will ensure that the image's meaning can be well communicated with user-agents, including screen browsers.

* If you rely on the browser to scale the image scale and can render a good effect when using img

* Use img if fit and z-index stretches the background image to fill its entire window

HTML&CSS FAQ (v)