The blank effect properties in CSS are used

White-space

White-space is used to set the browser to "blank" processing, the so-called Blank refers to the space you entered in the editor, enter, tab and so on. His optional content is as follows:

Normal: Default. The blank will be ignored by the browser. For example: whitespace at the beginning of the end ignores, between words, regardless of how many spaces or carriage returns, only one space is displayed, the space before the newline is ignored
Pre: The blank will be reserved by the browser. It behaves like a <pre> tag in HTML.
NoWrap: Do not wrap, unless you encounter <br/>,n a space is compressed into one.
Pre-wrap: Preserves all whitespace, but wraps normally (chrome,ff,ie8+,opera), equal to normal in IE6 and IE7
Pre-line: Merges whitespace sequences (merged into one), but preserves line breaks (Chrome,ff,ie8+,opera), which are equivalent to normal in IE6 and IE7

Word-spacing and Letter-spacing
Word-spacing can only be used in English words and words, for Chinese invalid
Letter-spacing can be used in Chinese.