/* ------------------------------------------
 * IT书包
 * 网址：www.itshubao.com
 * 整理：yinq<3331653644@qq.com> 
 -------------------------------------------- */
::-moz-selection { background: rgba(0,0,0,0.2); }
::selection { background: rgba(0,0,0,0.2); }

/**** Skip to line 36 for the hover code ****/

body {
  background: linear-gradient(to right,#07a, #0aa);
  background-size: 100%;
  font-family: 'Microsoft YaHei', sans-serif;
  font-size: 16px;
  line-height: 1.5em;
  margin: 80px 4em 0;
  color: #f5f5f5;
}
h1 {
  max-width: 49rem;
  font-size: 3.5em;
  line-height: 1em;
  font-weight: 700;
  margin: 0.25em auto;
}
h2 {
  max-width: 49rem;
  margin: 1.4em auto;
}
p {
  line-height: 1.5em;
  margin: 1.4em auto;
  max-width: 49rem;
  font-size: 1em;
  font-weight: 300;
}

/** Code for hover info **/

dfn {
  background: rgba(0,0,0,0.2);
  border-bottom: dashed 1px rgba(0,0,0,0.8);
  padding: 0 0.4em;
  cursor: help;
  font-style: normal;
  position: relative;
  
}
dfn::after {
  content: attr(data-info);
  display: inline;
  position: absolute;
  top: 22px; left: 0;
  opacity: 0;
  width: 230px;
  font-size: 13px;
  font-weight: 700;
  line-height: 1.5em;
  padding: 0.5em 0.8em;
  background: rgba(0,0,0,0.8);
  color: #fff;
  pointer-events: none; /* This prevents the box from apearing when hovered. */
  transition: opacity 250ms, top 250ms;
}
dfn::before {
  content: '';
  display: block;
  position: absolute;
  top: 12px; left: 20px;
  opacity: 0;
  width: 0; height: 0;
  border: solid transparent 5px;
  border-bottom-color: rgba(0,0,0,0.8);
  transition: opacity 250ms, top 250ms;
}
dfn:hover {z-index: 2;} /* Keeps the info boxes on top of other elements */
dfn:hover::after,
dfn:hover::before {opacity: 1;}
dfn:hover::after {top: 30px;}
dfn:hover::before {top: 20px;}