1、基本类.btn
{display/padding/margin-bottom/font-size/border-radius/border}
作用于< a:role:button >
2、预定义样式.btn-default .btn-primary .btn-success .btn-info .btn-warning .btn-danger .btn-link {color/background-color/border-color}
3、尺寸 .btn-lg .btn-md .btn-sm .btn-xs {padding/font-size/line-height/border-radius} .btn-block {display/width}
4、激活状态 .active {background-color/border-color/box-shadow}
5、禁用状态 disabled属性/.disabled {cursor/opcity}
图片
1、响应式 .img-responsive {max-width/height/display}
2、居中 .center-block {display/margin-left/margin-right}
3、形状 .img-rounded .img-circle {border-radius} .img-thumbnail {display/padding/background/border/border-radius}