Auxiliary of 3.BOOTSTRAP-CSS

Some helper classes that might come in handy:

Text class: If the text is a link, the mouse moves to the text to darken.

. text-muted	Text styles for the "text-muted" class
. text-primary	Text styles for the "Text-primary" class
. text-success	Text styles for the "Text-success" class
. text-info	Text styles for the "Text-info" class
. text-warning	Text styles for the "Text-warning" class
. Text-danger	Text styles for the "Text-danger" class

Background class:

. bg-primary	Table cells use the "bg-primary" class
. bg-success	Table cells use the "bg-success" class
. bg-info	Table cells use the "Bg-info" class
. bg-warning	Table cells use the "bg-warning" class
. Bg-danger	Table cells use the "Bg-danger" class

Other:

. pull-left	Element floats to the left
. pull-right	Element floats to the right
. center-block	Set the element to Display:block and center the display
. clearfix	Clear floating
. Show	Force element Display
. Hidden	Force element hiding
. sr-only	In addition to screen readers, hidden elements on other devices
. sr-only-focusable	Used in conjunction with the. Sr-only class to display when an element gets focus (for example, a user with a keyboard operation)
. text-hide	Replace the text content contained in a page element with a background map
. Close	Show Close button
. Caret	Show drop-down function

Auxiliary of 3.BOOTSTRAP-CSS