div.main
  | Что такое 
  span(attr="Каскадные таблицы стилей") CSS
  | ?
div.links
  a(href="https://webstacker.net", target="_blank") Webstacker
  a(href="https://t.me/webdevblog", target="_blank") Telegram
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*[attr] {
  position: relative;
  cursor: help;
  
  &:before {
    pointer-events: none;
    content: attr(attr);
    position: absolute;
    z-index: 1;
    opacity: 0;
    visibility: hidden;
  }
  
  &:hover:before {
    opacity: 1;
    visibility: visible;
  }
}

/**
 * Page Styles
 * You don't need this
 */
body {
  display: flex;
  flex-flow: column wrap;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
}

.main {
  padding: 30px;
  min-width: 200px;
  text-align: center;
  border: 1px solid #f3f3f3;
}

.links {
  margin-top: 5px;
  display: flex;
}

a {
  display: inline-block;
  padding: 5px;
}

*[attr] {
  color: green;
  border-bottom: 1px dotted green;
  
  &:before {
    margin-top: 10px;
    max-width: 100vw;
    font-size: 12px;
    color: #000;
    border-radius: 5px;
    background-color: #f1f1f1;
    padding: 5px 10px;
  }
  
  &:after {
    opacity: 0;
    visibility: hidden;
    content: '';
    position: absolute;
    width: 0; 
    height: 0; 
    border: 5px solid transparent;
    border-bottom-color: #f1f1f1;
  }
  
  &:before,
  &:after {
    top: 100%;
    left: 50%;
    transition: all .15s ease;
    transform: translate(-50%, 15px);
  }
  
  &:hover:before,
  &:hover:after {
    transition: all .15s ease;
    transform: translate(-50%, 0);
  }
  
  &:hover:after {
    opacity: 1;
    visibility: visible;
  }
}
View Compiled
/**
 * Специально для Webstacker.net
 * https://webstacker.net
 * https://t.me/webdevblog
 */
View Compiled

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