单行文本省略号

.ellipsis-row1 {
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
}

多行文本省略号

.ellipsis-row3 {
    overflow: hidden;
    display: -webkit-box;
    text-overflow: -o-ellipsis-lastline;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 3;
}

Sass合并

@for $lineCount from 1 through 3 {
    %ellipsis-row#{$lineCount} {
        overflow: hidden;
        @if $lineCount == 1 {
            white-space: nowrap;
            text-overflow: ellipsis;
        } @else {
            display: -webkit-box;
            text-overflow: -o-ellipsis-lastline;
            -webkit-box-orient: vertical;
            -webkit-line-clamp: $lineCount;
        }
    }
}

.section1 p {
    @extend %ellipsis-row1;
}
.section2 p {
    @extend %ellipsis-row2;
}
.section3 p {
    @extend %ellipsis-row3;
}

编译后：

.section1 p {
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
}
.section2 p {
    overflow: hidden;
    display: -webkit-box;
    text-overflow: -o-ellipsis-lastline;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 2;
}
.section3 p {
    overflow: hidden;
    display: -webkit-box;
    text-overflow: -o-ellipsis-lastline;
    -webkit-box-orient: vertical;
    -webkit-line-clamp: 3;
}