@collapse-prefix-cls: ~"@{css-prefix}collapse"; .@{collapse-prefix-cls}{ background-color: @background-color-base; border-radius: 3px; border: 1px solid @border-color-base; & > &-item{ border-top: 1px solid @border-color-base; &:first-child { border-top: 0; } > .@{collapse-prefix-cls}-header{ height: 38px; line-height: 38px; padding-left: 32px; color: #666; cursor: pointer; position: relative; > i{ .transition(transform @transition-time @ease-in-out); } } } & > &-item&-item-active > &-header > i{ .transform(rotate(90deg)); } &-content{ //display: none; overflow: hidden; color: @text-color; padding: 0 16px; background-color: #fff; & > &-box { padding-top: 16px; padding-bottom: 16px; } } &-item-active > &-content{ //display: block; } &-item:last-child { > .@{collapse-prefix-cls}-content { border-radius: 0 0 3px 3px; } } }