/* ------------------------------------------
 * IT书包
 * 网址：www.itshubao.com
 * 整理：yinq<3331653644@qq.com> 
 -------------------------------------------- */
a {
  position: relative;
  display: inline-block;
  padding: 1.2em 2em;
  text-decoration: none;
  text-align: center;
  cursor: pointer;
  -webkit-user-select: none;
     -moz-user-select: none;
      -ms-user-select: none;
          user-select: none;
  color: white;
}
a::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  background: -webkit-linear-gradient(315deg, #6e8efb, #a777e3);
  background: linear-gradient(135deg, #6e8efb, #a777e3);
  border-radius: 4px;
  -webkit-transition: box-shadow .5s ease, -webkit-transform .2s ease;
  transition: box-shadow .5s ease, -webkit-transform .2s ease;
  transition: box-shadow .5s ease, transform .2s ease;
  transition: box-shadow .5s ease, transform .2s ease, -webkit-transform .2s ease;
  will-change: transform;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
  -webkit-transform: translateY(var(--ty, 0)) rotateX(var(--rx, 0)) rotateY(var(--ry, 0)) translateZ(var(--tz, -12px));
          transform: translateY(var(--ty, 0)) rotateX(var(--rx, 0)) rotateY(var(--ry, 0)) translateZ(var(--tz, -12px));
}
a:hover::before {
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
}
a::after {
  position: relative;
  display: inline-block;
  content: attr(data-title);
  -webkit-transition: -webkit-transform .2s ease;
  transition: -webkit-transform .2s ease;
  transition: transform .2s ease;
  transition: transform .2s ease, -webkit-transform .2s ease;
  font-weight: bold;
  letter-spacing: .01em;
  will-change: transform;
  -webkit-transform: translateY(var(--ty, 0)) rotateX(var(--rx, 0)) rotateY(var(--ry, 0));
          transform: translateY(var(--ty, 0)) rotateX(var(--rx, 0)) rotateY(var(--ry, 0));
}

body {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  height: 100vh;
  -webkit-transform-style: preserve-3d;
          transform-style: preserve-3d;
  -webkit-transform: perspective(800px);
          transform: perspective(800px);
}